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Hi friends, welcome back to the Saving Bread Podcast.
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Today is a lessons episode, and it's one that I think people have been waiting for for a long time, not just because of the podcast, but I think pH is probably one of the things that I get asked questions most often about.
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I would not say that I am like the leading expert in pH by any means, but in some circles, I feel like I am associated with using it more often than maybe other bakers do.
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And I learned about pH from Tomas Tefri Shimblon, who I mentioned in the last episode, his class, modern bread and vinoiserie at SFBI, totally changed my life.
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In that class, we used pH a little bit for bread, but mostly for panetone, brioche, again, vinoiserie.
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And when I learned about it, I came home and I am not a person to make brioche or panettone.
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I tried my hand at it and it came out really well, but I was having to use a lot of shipped white flour, and in the end, it just wasn't something that ended up sticking.
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And I decided that I was going to give it a little rest until I could find a more ethical flour to use.
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But I started using pH in every single one of my bake days to feed my Levant, to divide my dough for shaping.
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I was just poking my pH meter in all the doughs and recording everything.
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And that was probably a little over three years ago now.
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So I've learned a lot in that time, and I'm looking forward to sharing it with you.
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One more sort of like housekeeping thing before we get started.
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If you follow me on Instagram on social media at MatriarchBread, you may have seen that I recently just announced that I will be teaching a class with Alex from Wild Woman.
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And she was on the podcast.
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She was our second guest.
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And another friend of mine, Lila from The Early Rise, who will eventually be on the podcast.
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And she was also the creator of West Coast Breadfest, which has come up quite a few times on the podcast already.
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If that's something you're interested in learning more about, please follow me on social media again, matriarch.bred, and there will be lots more information posted there.
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But I just wanted to give it a little shout out because it's a passion project and something we've been talking about for a really long time.
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And I won't share too much more than that here on the podcast.
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But just in case you wanted to find out some more, yes, please head over to my Instagram.
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But for today, we are going to focus on PH, Sourdough Microbiology, and we are just going to get into it.
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So it was a very long intro, but this is a topic that I'm really passionate about and something I look forward to diving a little bit deeper with all of you.
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I'm Allie White, and this is Saving Bread.
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But now that I've been using it for quite a few years, a little over three years, I'm not as married to it as I was initially.
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I've learned that there's a lot more wiggle room than I originally thought.
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And there's just a lot of other pieces of the puzzle.
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So I think what I want to do is get a little bit deeper into the microbiology of sourdough, some of the things that I've learned about what's even in a sourdough culture.
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And then I would like to explain to all of you how I use pH.
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You will never hear me claim that there's only one way to do things, or that my way is the best way.
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I consider myself at the beginning of my baking journey.
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I am very thankful for the experiences that I've had, for the people that I've learned from.
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I've had incredible mentors, wonderful people holding my hand along the way who have taught me so much.
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And I'm really, really thankful for that.
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Each one of those experiences has taught me that there is no one way to make bread.
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I have no angle here.
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I have no ego about this.
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I simply like to share what I've learned, share what I've experienced in my real life in my bakery, and wonderful things that I've also learned from others.
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Any guest that I have on, I am highlighting what they are good at, what they love to do, what they have learned.
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I think it's really important, especially what I'm hoping to cultivate in this space for saving bread is that it's not about being right.
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It's not about winning, it's not about who can make the best bread.
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It's just sharing information.
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So when I talk about this today, please know that my intention is just to share what I have experienced and what I've learned.
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And I'm always open to building upon that, learning from others, collaborating with others.
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And I really hope that when you hear this, you take away something valuable that you can add into your practice at home and take what you like and leave what you don't.
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Okay, so again, today I want to talk about the microbiology of sourdough, not at a level where we need to memorize organisms or biochemical pathways.
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I want to cover enough of the science to understand what is happening during fermentation and more importantly, how that information can make us better bakers.
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Why does dough rise?
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Why does the pH fall?
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Why does dough eventually begin to lose strength?
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Why does whole grain dough behave differently than a mostly white flour country loaf?
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And what information are we actually getting when we measure pH?
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Understanding some of this changed the way that I think about fermentation.
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Instead of asking whether a dough has fermented for the number of hours written in a formula, I'm much more interested in what actually happened inside of that dough during those hours.
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So let's start with the starter.
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What is living in a sourdough starter?
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A sourdough starter, or perhaps it's a lavan that you've built to go into one of your mixes.
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It's a mixed microbial culture.
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The two groups that matter the most to us as bakers are yeasts and lactic acid bacteria, usually shortened to LAB or lab.
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There can be many different species of both.
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You may have heard some really fancy names.
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If you want to go down those rabbit holes of what's what, I strongly encourage you to do that on your own time, but I don't think knowing the names is the important part.
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I don't want to lose anyone here because the science gets too complicated or too difficult to say.
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Studies of sourdough starters have found a lot of microbial diversity.
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Flower type, hydration, temperature, feeding frequency, feeding ratio, and other conditions can all influence which organisms become established.
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That's one of the reasons two healthy starters can behave differently.
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The important point for this episode is that a starter contains a community of microorganisms living together in an environment we create through the way we maintain it.
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What does the yeast do?
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Yeast is one of the main drivers of leavening.
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Yeasts use available sugars during fermentation and produce carbon dioxide and ethanol.
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The carbon dioxide becomes trapped within the dough's gluten network.
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As more gas accumulates, the dough will expand.
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So when we see a starter or a dough rising or increasing in volume, gas production is part of what we are observing.
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Some lactic acid bacteria can also produce carbon dioxide.
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So yeast is not the only possible source of gas and sourdough, but in most wheat sourdough bread systems, yeast is the main contributor to leavening.
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The other major product of yeast fermentation is ethanol, but most of that ethanol is lost during baking.
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So yeast gives us a major part of the physical rise we associate with fermentation.
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But the microorganisms need fermentable carbohydrates to do this, they need food.
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And so that brings us to our flour.
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There are enzymes in flour.
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Flour contains naturally occurring enzymes.
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One important group of enzymes is called amylase.
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Amylases act on starch.
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Starch is made from long chains of glucose molecules.
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Enzymes break those large starch molecules into smaller carbohydrates that can then become available during fermentation.
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Two terms that you may hear are alpha amylase and beta amylase.
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They act on starch differently.
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Alpha amylase breaks starch chains internally and produces smaller starch fragments, including dextrins.
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And then beta amylase works from the ends of starch chains and releases maltose.
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You don't really need to remember any of those specific mechanisms.
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The useful part for the baker is this.
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We start with the starch in the flour.
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Enzymes break some of that starch into smaller carbohydrates.
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This happens as soon as the water is added to the flour.
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Those carbohydrates become available to yeast and bacteria, and the microorganisms then ferment them.
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So fermentation is not just yeast being added to flour and producing gas.
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There's already enzyme activity taking place inside of the dough with the flour and the water that affects the carbohydrates available to the microorganisms.
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Lactic acid bacteria are the other major group in sourdough starter.
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Lab use carbohydrates and produce organic acids.
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Lactic acid is one major product of all of this, depending on the species and fermentation pathway.
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They may also produce acetic acid, carbon dioxide, ethanol, and a number of other compounds.
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These organisms are a major reason that sourdough becomes acidic.
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It has that tangy flavor.
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As organic acids accumulate during fermentation, the pH generally begins to fall.
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The acids and other metabolites produced during fermentation also contribute to the flavor and the aroma of sourdough bread, that signature tang.
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This is where yeast and bacteria need to be thought about together.
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They are not doing identical jobs, but they are living in the same fermentation environment and affecting that environment at the same time.
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So temperature matters, flour matters, hydration matters, how often you feed your starter matters, the amount of starter you carry into the next feeding matters.
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All of these variables can influence fermentation and over time the microbial community itself.
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That is the one reason I think consistency is just so important when you're learning your starter's behavior.
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If you change several variables every single day, it becomes very difficult to understand why the starter has behaved differently.
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So let's talk about pH.
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I use pH frequently in my baking, but pH is one measurement of fermentation.
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It is not fermentation itself.
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That distinction is really important.
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I'm still looking at the dough.
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I look at the amount of expansion.
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I look at the bubbles, I feel the strength and extensibility.
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I take into consideration the dough temperature.
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I'm thinking about which flowers I used for my mix, and I use pH as another piece of information.
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So what does pH even mean?
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The pH scale runs from zero all the way to 14.
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7 is neutral.
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Numbers below 7 are considered acidic, and numbers above 7 are called alkaline.
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For our purposes, that means the difference between something at pH 5 and something at pH 4 is much greater than the numbers make it appear.
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During sourdough fermentation, organic acids accumulate and pH generally falls.
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A freshly mixed bread dough might begin somewhere in the mid-fives or higher, 5.5, maybe 5.6, depending on the flour, the lavan, and the formula.
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If we're talking about the same country dough, the same one that we've been using since the beginning of the podcast, with about 20% whole grain and the rest is white flour, you can expect the pH to begin somewhere around 5.5 or 5.6 once the lavan has been added.
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As the fermentation continues, that number will decrease.
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It will become lower and lower with time.
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If my dough begins around 5.5 and later reaches 4.8, I now have measurable evidence that acidification has occurred.
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But pH does not tell us the entire story of acidity, and that becomes especially important with whole grain.
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So let's talk about pH versus total acidity.
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You may hear another measurement called TTA or total titratable acidity.
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I do not think most bakers need to measure TTA at home, but it helps to understand what it represents.
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So pH tells us about the hydrogen ion activity in the dough.
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TTA is measured by adding a base to a sample until a defined endpoint is reached.
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The amount of base required gives us information about the titratable acids and the buffering system in that dough.
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These are big words.
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Don't get lost.
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I just need to get through this part so you can understand the limitations of pH.
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So pH and TTA are related, but they are not interchangeable.
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Two doughs can have similar pH readings and still have a different titratable acidity.
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This is especially relevant with whole grain.
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Whole grain flour generally has a greater buffering capacity than refined flour.
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That is partly related to the greater amount of minerals and other compounds present in the outer portion of the grain.
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A more highly buffered dough can accumulate more acid without showing the same change in pH that we might see in a less buffered dough.
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This is one of the reasons I'm careful about treating pH targets as universal numbers.
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The flower really matters.
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Let's talk about a young versus a mature Levan.
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This is another area where I think the language can become too rigid.
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I sometimes use pH as part of the way that I evaluate the maturity of a lavan.
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In my own baking, I often like to use a lavan somewhere around pH 4.0 to 4.2.
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This is a range that works well for many of my doughs and for the way that I maintain my lavan.
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If I allow the lavan to ferment longer and become more acidic, I may see it drop into the high threes.
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But there is not one pH number where a lavan suddenly changes from young to mature or where the yeast suddenly stops working.
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As the lavan continues fermenting, several things happen.
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Sugars and other nutrients are being consumed, acids are accumulating, the environment is becoming more acidic, and microbial metabolism is changing.
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And eventually the structure of the lavan itself can weaken.
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So I look at pH along with the rest of the lavan.
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How long is it fermented?
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What temperature was it held at?
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How much has it risen?
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What does it smell like?
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What does the structure look like?
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And what kind of dough am I planning to put it into?
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The Levan I want for one bread may not be exactly the same lavan I want for another.
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I want to pause here and say, I use the Hannah bread and dough pH meter.
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I have the Bluetooth version and I have the one that doesn't have Bluetooth.
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They work very similarly, in my opinion.
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I enjoy using both of them.
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Most meters, specifically that meter, because of the acids that are in the dough, as the hydrogen starts to accumulate, as the acidity begins to build, those meters cannot read below, I believe it's 3.9.
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So if you stick a pH meter in your dough and you're getting a reading of 3.8, it's basically impossible to have an accurate reading at that point.
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I personally only trust any readings that I get from my pH meter between 3.9 and higher.
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So I just wanted to pause there and say that.
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But this is very convenient because typically, as you'll learn as the podcast goes along, I don't like to let either my Levant or my dough drop below pH 4.0.
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But I do think it's important to understand that if you do purchase a meter, any of the readings that come from it can really only be trusted from, in my experience, 3.9 and higher.
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Okay?
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Let's get back to it.
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Let's talk about protease and dough strength.
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There's another group of enzymes worth talking about because it helps explain what happens to dough during a long fermentation.
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Proteases break proteins into smaller peptides and amino acids.
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Wheat flour contains its own proteolytic enzymes.
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The microorganisms in sourdough also contribute to protein and peptide metabolism.
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As sourdough becomes more acidic, as the dough becomes more acidic and the pH begins to drop, some of the cereal proteases in that dough become more active.
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Research commonly describes significant cereal protease activity.
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Once sourdough becomes fairly acidic, especially below roughly pH 4.5, some protein breakdown is definitely a normal part of fermentation.
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It contributes to the pool of peptides and amino acids in the dough, which can also contribute to flavor development.
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But if fermentation continues too far, the dough can eventually lose strength.
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You already recognize this.
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All bakers already know this intuitively because the dough becomes increasingly slack, it becomes sticky, it spreads more easily, it becomes difficult to build tension during shaping.
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That loss of structure is not caused by one enzyme alone: acidification, proteolysis, fermentation time, flower strength, hydration, temperature, and mechanical handling all play a role.
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So I would not look at a weak dough and say, uh, protease did this.
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If you turn your dough out and it just flops into a pancake after it's been in the fridge all night, it's not just the work of one enzyme, but protein breakdown is part of the larger process occurring as a dough ferments and acidifies.
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This is why fermentation is a balance.
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We need enough fermentation to produce gas, flavor, and the dough characteristics that we want, but we also need the dough to retain enough structure to hold that gas.
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It's a game, it is a balancing act and it.
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Takes a lot of practice.
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So, how do I apply this to my country dough?
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So, I want to bring out all of this microbiology and put it into actual bread.
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So, for my country dough, the one that we've been talking about since the beginning of the podcast, 20% whole grain, 20% lavan, 10% prefermented flour.
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The exact formula maybe changes a little bit, but the fermentation pattern is fairly consistent.
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After mixing, the dough will likely rise into a pH range of the mid-5s, 5.5, 5.4, somewhere around there.
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Then bulk fermentation begins.
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You've added your Levan to your dough, the pH has risen.
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We have entered the beginning of bulk fermentation.
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Dough temperature is a major variable.
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Remember, for my country dough, I generally work with a desired dough temperature, somewhere around 77 to 82 degrees Fahrenheit, really depending on the time of year and my production schedule.
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Bulk fermentation might take somewhere around three to four hours in my system.
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But the important point is that three hours does not automatically mean that the dough is finished, right?
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We're looking at the dough, we're using temperature, we're using time, we're using pH all together.
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As fermentation progresses, I watch the dough expand and develop while the pH falls.
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For my current country dough, I may divide somewhere around pH 4.7 to 4.6.
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That number is in no way a universal recommendation.
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I am telling you what I do in my system in production.
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This is a target I've developed using my exact flour, my lavan, my inoculation, my temperatures, everything.
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After dividing, I still have fermentation ahead of me.
00:23:55.680 --> 00:24:03.920
Depending on the dough, I may pre-shape, allow it to rest, final shape, and give it additional time in the banner in the basket.
00:24:04.160 --> 00:24:10.160
But typically, I want to get my dough into the fridge around 4.3.
00:24:10.480 --> 00:24:14.720
That's what works for my refrigerator that I keep at 36 degrees Fahrenheit.
00:24:14.880 --> 00:24:18.720
So if you remember, we started bulk fermentation in the mid-fives.
00:24:18.880 --> 00:24:24.559
We allowed the pH to drop to around 4.7, maybe 4.6.
00:24:24.799 --> 00:24:39.119
We've divided the dough, and in that time I need to divide, pre-shape, let it rest, final shape, and have some time in the basket and get it into the refrigerator around 4.3, sometimes 4.2.
00:24:39.279 --> 00:24:41.839
That is what works with my system.
00:24:42.640 --> 00:24:46.480
I'm looking at how much time I have, where does that dough need to go?
00:24:46.640 --> 00:24:56.480
What are all the steps, knowing that I need to get into the fridge by a specific endpoint, and it helps me manage my time for my dough for that production day.
00:24:56.720 --> 00:25:00.799
The pH will continue to drop during the cold retard.
00:25:01.039 --> 00:25:13.039
By the time I take my dough out of the fridge the next day, approximately 12 to 18 hours later, typically my dough has come all the way down to pH 4.0 or 4.1.
00:25:13.119 --> 00:25:18.720
Again, those are my numbers in my experience in my home with my dough.
00:25:18.960 --> 00:25:26.319
What makes them useful is that I repeat the process every single time.
00:25:26.960 --> 00:25:34.640
I have all of my checkpoints that I repeat so that I can bake consistently from week to week to week.
00:25:34.799 --> 00:25:39.119
Your numbers may be different than mine, and that is okay.
00:25:40.079 --> 00:25:58.559
The point isn't to copy my system, it's to know your own system, have measurements that you take along the way, time, temperature, flower, pH, and repeat your system at home week after week after week, especially if you're in production.
00:25:58.720 --> 00:26:01.759
The refrigerator does not stop fermentation immediately.
00:26:01.839 --> 00:26:15.680
So this is a really important part of my process, especially during the summer when it's hot and like the dough is hot, the mixer's hot, the flour's hot, everything's hot, the water's coming out of the tap hot, like it's hard to manage, right?
00:26:16.079 --> 00:26:17.279
This is an important part.
00:26:17.440 --> 00:26:18.880
This is an important piece of the puzzle.
00:26:19.039 --> 00:26:28.880
When the dough goes into the refrigerator, fermentation slows as the dough cools, but it doesn't stop the instant the basket enters the refrigerator.
00:26:29.039 --> 00:26:38.000
A warm loaf has to lose that heat and the center of the dough, specifically like right through the middle, it takes time to cool down.
00:26:38.079 --> 00:26:41.200
And it honestly will probably never get to fridge temp.
00:26:41.279 --> 00:26:48.720
It's always going to be a couple of degrees warmer, especially if you have a ton of dough in the fridge or you're opening and closing the fridge for other purposes.
00:26:48.960 --> 00:26:59.039
So, how quickly that happens really depends on the refrigerator temperature, airflow, dough size, again, how much warm dough is loaded into the fridge at one time.
00:26:59.200 --> 00:27:02.079
So this really matters in bakery production.
00:27:02.240 --> 00:27:10.559
Putting one loaf in a cold refrigerator is totally different from loading a refrigerator with dozens of warm loaves.
00:27:10.799 --> 00:27:21.359
So when I choose the point where the loaf goes into the cold retard, I am accounting for the fermentation that will continue while the dough cools.
00:27:21.519 --> 00:27:25.440
Some days that might take a lot longer than other days.
00:27:25.599 --> 00:27:33.440
Seasonality, time of year, outdoor temperature, all these things, like your fridge works so hard in the summer to keep things cool.
00:27:33.599 --> 00:27:39.039
You really need to think about all of these things and decide: does this dough need to go in sooner?
00:27:39.279 --> 00:27:41.279
Can it go in a little bit later?
00:27:41.519 --> 00:27:46.400
These are the decisions that seasoned bakers are making every single bake day.
00:27:46.799 --> 00:27:54.480
So, what changes when we move from a standard country dough to a dough with a high amount of whole grain?
00:27:54.720 --> 00:27:59.519
Because I approach high whole grain dough completely differently.
00:27:59.759 --> 00:28:04.720
Whole grain introduces the bran and the germ along with the endosperm.
00:28:05.039 --> 00:28:12.319
Bran changes the physical behavior of the dough and can interfere with the development and continuity of the gluten network.
00:28:12.559 --> 00:28:20.880
Whole grain flour also contains more minerals and other compounds and generally has greater buffering capacity, which we talked about earlier.
00:28:20.960 --> 00:28:26.319
It can be harder to get an accurate reading of how much acid is actually in that dough.
00:28:26.480 --> 00:28:34.160
You have to be an intuitive baker in some ways when you start working with more whole grains because you cannot rely on data alone.
00:28:34.319 --> 00:28:39.279
Its enzyme activity and fermentation behavior can also differ from refined flour.
00:28:39.440 --> 00:28:48.480
So I do not assume that my country low fermentation targets should transfer directly to a dough containing 50, 80, or even 100% whole grain.
00:28:48.559 --> 00:28:56.160
For a dough with 50% whole grain or more, to give myself a little bit more wiggle room.
00:29:01.920 --> 00:29:08.720
Whereas with my country dough, I can allow it to come down a little bit more, closer to pH 4.1, 4.0.
00:29:09.119 --> 00:29:13.119
But I do like a tiny bit of wiggle room for the whole grain.
00:29:13.200 --> 00:29:15.039
But again, it's a range.
00:29:15.119 --> 00:29:17.440
You will figure out what works for your system.
00:29:17.920 --> 00:29:27.359
My desired dough temperature for my whole grain loaves typically is around 80 degrees, and bulk in my production system takes around three hours.
00:29:27.759 --> 00:29:32.559
But I typically divide that dough much earlier in terms of acidification.
00:29:32.640 --> 00:29:41.039
So closer to pH 5.0, maybe 4.9, depending on what I'm doing after that.
00:29:41.279 --> 00:29:51.200
If I want to pre-shape, bench rest, final shape, basket proof, I typically need to divide on the earlier side, around 5.0.
00:29:51.599 --> 00:29:58.799
If I'm skipping the pre-shape, which sometimes happens when things are moving quickly, the dough might come down to around 4.8.
00:29:58.960 --> 00:30:02.480
At that point, I'm completely skipping the divide and pre-shape.
00:30:02.559 --> 00:30:09.119
I'm going directly to the final shape, directly in the basket, a short basket rest, and then I'm into the fridge.
00:30:09.440 --> 00:30:16.799
No matter what, like hell or high water for whole grain doughs, I am in my refrigerator at pH 4.7.
00:30:17.920 --> 00:30:27.599
Getting in that early the next day, when I come back to my dough from the fridge, I'm coming out around 4.3-ish, 4.4.
00:30:27.759 --> 00:30:33.599
There is a pretty big drop that happens with whole grain dough in the cold retard.
00:30:33.759 --> 00:30:38.319
So those numbers are intentionally higher than the numbers I use with my country loaf.
00:30:38.400 --> 00:30:44.960
I'm working with a dough that has different flour composition, different buffering capacity, and different structural limitations.
00:30:45.119 --> 00:30:50.480
There are, gosh, so many ways to make an excellent whole grain bread.
00:30:50.640 --> 00:30:55.440
These are the numbers that work for me within my process.
00:30:55.599 --> 00:31:13.519
So rather than asking what is the correct pH for bread, I think it's more useful to think about it as what pH corresponds with the fermentation I want when I use this flour, this formula, this temperature, and this process.
00:31:13.839 --> 00:31:17.599
That gives that number context, okay?
00:31:17.839 --> 00:31:20.000
Flour changes the fermentation environment.
00:31:20.160 --> 00:31:22.960
This is another reason I think flour selection matters so much.
00:31:23.119 --> 00:31:27.279
When we change the flour, we are changing more than just the protein percentage.
00:31:27.440 --> 00:31:37.279
Different flowers bring different amounts of minerals, enzymes, damaged starch, nutrients, and microorganisms into the dough.
00:31:37.519 --> 00:31:43.279
Whole grain includes parts of the kernel that have been removed for refined flour.
00:31:43.359 --> 00:31:48.160
So changing the flour absolutely changes fermentation behavior.
00:31:48.319 --> 00:31:53.039
This is why a whole grain starter may behave differently from a white flour starter.
00:31:53.200 --> 00:32:01.680
And it is why when someone is trying to understand their starter, I recommend keeping the maintenance routine fairly consistent for a while.
00:32:01.920 --> 00:32:07.759
Use the same flour, use the same feeding ratio, try to keep the temperature consistent.
00:32:08.079 --> 00:32:10.960
Observe how long it takes to rise.
00:32:11.200 --> 00:32:14.240
Pay attention to the aroma and the structure.
00:32:14.400 --> 00:32:15.519
Maybe taste it.
00:32:15.759 --> 00:32:24.000
Measure the pH if that's a tool that you want to use, and then change one variable and see what happens.
00:32:24.240 --> 00:32:27.599
That gives you useful information.
00:32:27.759 --> 00:32:30.880
Let's talk about a question I am asked frequently.
00:32:31.039 --> 00:32:34.640
Does a lower pH mean a more sour loaf?
00:32:34.799 --> 00:32:36.240
Not necessarily.
00:32:36.640 --> 00:32:41.519
pH and perceived sourness are related, but it's not the same thing.
00:32:41.680 --> 00:32:46.880
Sourdough contains multiple organic acids and many other flavor compounds.
00:32:47.119 --> 00:32:52.640
Lactic acid and acetic acid also have different sensory qualities.
00:32:52.960 --> 00:33:00.000
pH alone does not tell you exactly how much of each acid is present, although it'd be really cool if it did.
00:33:00.240 --> 00:33:06.319
It also does not tell you how sour a person will perceive the bread to be.
00:33:06.559 --> 00:33:12.559
So two loaves with a similar pH measurement may still taste different.
00:33:12.799 --> 00:33:20.319
This is another reason to treat pH as one measurement instead of using it as a complete description of the bread.
00:33:20.880 --> 00:33:22.960
Does sourdough break down gluten?
00:33:23.279 --> 00:33:28.480
This is another area where I get a lot of questions, and I think we should be very thoughtful about our language.
00:33:28.720 --> 00:33:33.119
Protein breakdown does occur during sourdough fermentation.
00:33:33.359 --> 00:33:34.079
Absolutely.
00:33:34.400 --> 00:33:41.519
Acidification activates cereal proteases, and microorganisms also participate in peptide metabolism.
00:33:41.839 --> 00:33:51.279
So the protein structure of a fermented dough is not exactly the same as it was immediately after mixing.
00:33:51.519 --> 00:33:58.000
Normal sourdough fermentation does not make ordinary wheat bread gluten-free.
00:33:58.079 --> 00:34:00.079
And we should never claim that it does.
00:34:00.640 --> 00:34:14.639
Regular sourdough wheat bread should not be considered a safe food for someone with celiac disease unless it meets the specific standards required for a gluten-free food.
00:34:14.880 --> 00:34:19.280
I don't know what it is, but it's like some parts per million or parts per billion.
00:34:19.440 --> 00:34:21.760
You would have to get that food item tested.
00:34:21.920 --> 00:34:25.360
We cannot make these health claims as bakers.
00:34:25.440 --> 00:34:32.960
So please be responsible with the words that you choose when you are marketing and selling your bread to the community.
00:34:33.440 --> 00:34:49.119
There has been research using specific microorganisms and carefully controlled fermentation processes to achieve extensive gluten degradation, but that is very different from making a normal loaf of sourdough at home or in a bakery.
00:34:49.199 --> 00:34:57.840
So I think it's accurate to say that sourdough fermentation modifies and partially breaks down grain proteins.
00:34:57.920 --> 00:35:08.960
But I would not describe standard sourdough bread as gluten-free or make any broad claims that it's automatically easier for anyone to digest.
00:35:09.840 --> 00:35:12.559
So what's actually happening during fermentation?
00:35:12.800 --> 00:35:19.440
When we mix flour, water, salt, and lavan, several processes are happening at the same time.
00:35:19.679 --> 00:35:23.039
Enzymes in the flour are acting on starches and proteins.
00:35:23.199 --> 00:35:27.760
Yeasts are fermenting available sugars and producing carbon dioxide and ethanol.
00:35:28.000 --> 00:35:34.400
Lactic acid bacteria are metabolizing carbohydrates and producing organic acids and other compounds.
00:35:34.639 --> 00:35:36.400
The pH is falling.
00:35:36.639 --> 00:35:38.559
Gas is accumulating.
00:35:38.800 --> 00:35:41.599
The dough structure is changing.
00:35:41.840 --> 00:35:44.239
The profile is developing.
00:35:44.480 --> 00:35:51.840
None of these processes happen in isolation and they do not all move at the exact same rate.
00:35:52.000 --> 00:36:01.039
That's why temperature has such a huge effect on bread, and it's why flour has such a large effect and why hydration can change the way fermentation behaves.
00:36:01.199 --> 00:36:06.239
And it's why fermentation cannot be completely described with a clock.
00:36:06.400 --> 00:36:09.199
Here's what I want bakers to take away from this chat today.
00:36:09.519 --> 00:36:15.679
You do not need to understand every organism in your starter to make good bread.
00:36:15.840 --> 00:36:18.719
You also don't need a pH meter.
00:36:18.960 --> 00:36:34.400
What I find useful about understanding the science is that it gives context to the things we already observe in the real world with our eyes, with our nose, with our ears, and it gives context to our senses.
00:36:34.559 --> 00:36:38.480
If the dough is rising, gas is probably being produced and retained.
00:36:38.639 --> 00:36:45.920
If the pH is falling or the dough is tasting and smelling more sour, acidification is occurring.
00:36:46.239 --> 00:36:58.480
If the dough becomes increasingly extensible or eventually begins losing strength, biochemical and physical changes have been occurring throughout fermentation.
00:36:59.119 --> 00:37:02.559
The goal is to connect those observations.
00:37:03.119 --> 00:37:05.039
Look at what's in front of you.
00:37:05.199 --> 00:37:16.480
Look at the dough, touch it, pay attention to your temperature, watch its expansion, notice how the surface changes.
00:37:17.119 --> 00:37:18.079
Smell it.
00:37:18.239 --> 00:37:22.320
And if you use a pH meter, record that information too.
00:37:22.880 --> 00:37:25.679
Then look at the bread that you baked.
00:37:26.239 --> 00:37:28.800
That's where all this information becomes useful.
00:37:28.960 --> 00:37:40.480
If I consistently divide a dough at pH 4.7 and I like the bread that comes from it, that number becomes meaningful within my process.
00:37:41.199 --> 00:37:49.840
If I change the flour and suddenly the same target gives me a very different loaf, that tells me I need to reconsider the target.
00:37:50.159 --> 00:38:05.760
If my whole grain dough consistently loses strength before reaching the same pH as my country dough, I should not keep pushing it just because I have decided that one particular number means fermentation is finished.
00:38:05.840 --> 00:38:07.760
That is not how it works.
00:38:08.000 --> 00:38:10.639
That is the way I use pH.
00:38:10.719 --> 00:38:13.280
It helps me document what the dough is doing.
00:38:13.360 --> 00:38:22.960
It helps me repeat results and it helps me identify what changed when a bake does not go the way that I expected it to.
00:38:23.119 --> 00:38:29.039
The number is most useful when it is actually connected to the dough that is physically in front of you.
00:38:29.199 --> 00:38:33.599
And I think that is really the point of understanding the microbiology.
00:38:33.760 --> 00:38:40.000
We do not need the science to make bread more complicated.
00:38:40.239 --> 00:38:45.119
We can go there, you can go there, but we don't need to go there.
00:38:45.280 --> 00:38:48.320
We use it to better understand what we're already seeing.
00:38:48.559 --> 00:38:50.960
Yeast and bacteria are fermenting the dough.
00:38:51.199 --> 00:38:57.039
Flour enzymes are helping make nutrients available and changing the dough along the way.
00:38:57.519 --> 00:39:01.199
Organic acids are accumulating and pH is falling.
00:39:01.440 --> 00:39:05.119
The structure is developing and eventually it will begin to weaken.
00:39:05.280 --> 00:39:14.400
And our job as bakers is to decide when that dough has reached the point that we want.
00:39:14.719 --> 00:39:27.039
That decision comes from the combination of time, temperature, flour, feel, visual cues, most importantly, experience.
00:39:27.519 --> 00:39:30.480
And if you choose to use it, pH.
00:39:30.880 --> 00:39:40.480
The more of those pieces that we understand, the easier it becomes to build a fermentation process that works consistently for the bread we actually want to make.
00:39:41.519 --> 00:39:44.880
I think that's more than enough information for today.
00:39:45.360 --> 00:39:48.719
I want to just remind you some of my key points.
00:39:49.119 --> 00:39:55.119
I typically like to work within a pH range of 4.0 to 5.5.
00:39:55.519 --> 00:39:59.920
That gives me the end and the beginning.
00:40:00.159 --> 00:40:02.880
The beginning is I mix a Levan or a dough.
00:40:02.960 --> 00:40:06.159
That pH rises all the way up into the mid-fives.
00:40:06.400 --> 00:40:12.400
And through time, it drops all the way down to pH around 4.0.
00:40:12.559 --> 00:40:17.840
Whether I'm working with Levan or dough, I will not let my pH drop below that number.
00:40:18.079 --> 00:40:24.159
If I'm feeding my starter, I'm making sure to catch it between 4.0, 4.1.
00:40:25.039 --> 00:40:29.760
If I'm baking, I really want to get into the oven between 4.0 and 4.1.
00:40:29.920 --> 00:40:38.400
You will learn that there's a pattern to these numbers and something I can't really explain, but it's just consistencies that I've noticed over time.
00:40:38.559 --> 00:40:43.760
So if you decide to begin playing with the pH meter, I would love to hear about your experience.
00:40:43.920 --> 00:40:45.199
I'm always learning.
00:40:45.280 --> 00:40:47.360
I'm always open to new ideas.
00:40:47.599 --> 00:40:54.480
I'm not saying this is the one right way, but I have been recording all of my pH measurements for quite a few years now.
00:40:54.559 --> 00:40:56.639
And I've I've really enjoyed the process.
00:40:56.719 --> 00:40:57.760
It's fun for me.
00:40:57.920 --> 00:40:58.880
I like information.
00:40:59.039 --> 00:41:12.400
I like data, but I've also learned that repetition and um leaning into your senses and taking a happy heart and a happy spirit into the bakery is equally as important.
00:41:12.639 --> 00:41:16.800
So try not to close yourself off to any part of that.
00:41:16.960 --> 00:41:20.320
Allow yourself to experience all the different ways to make bread.
00:41:20.559 --> 00:41:24.719
And again, take the parts that you love and leave the ones that you don't.
00:41:24.960 --> 00:41:27.840
So I hope you learned a few things today.
00:41:28.000 --> 00:41:34.400
If you want to send me a message on Instagram or shoot me a message through BuzzSprout, I would love to hear from you.
00:41:34.559 --> 00:41:43.840
If you've been enjoying the podcast, if you could take just a couple of minutes now to leave us a review on Spotify or Apple Podcasts, it would really mean the world to me.
00:41:44.159 --> 00:41:48.559
And I have a lot of really fun things that I'm working on behind the scenes.
00:41:48.639 --> 00:41:51.599
And some of them are specifically for you, the listeners.
00:41:51.840 --> 00:41:55.599
So stay tuned, keep listening, keep sharing.
00:41:55.760 --> 00:42:03.920
And next week, I'll be back with an interviews episode with two people who I know you'll be very excited to hear from.
00:42:04.079 --> 00:42:05.599
That's it for today, friends.
00:42:05.920 --> 00:42:06.559
Bye.
00:42:07.920 --> 00:42:11.440
Thank you for listening to the Saving Bread Podcast.
00:42:14.159 --> 00:42:17.519
Music by Joshua from Dope.
00:42:19.760 --> 00:42:21.360
I'm Allie White.
00:42:22.079 --> 00:42:26.800
And as always, happy baking and long live real bread.
00:00:00.000 --> 00:00:03.359
Hi friends, welcome back to the Saving Bread Podcast.
00:00:03.680 --> 00:00:19.839
Today is a lessons episode, and it's one that I think people have been waiting for for a long time, not just because of the podcast, but I think pH is probably one of the things that I get asked questions most often about.
00:00:20.559 --> 00:00:32.479
I would not say that I am like the leading expert in pH by any means, but in some circles, I feel like I am associated with using it more often than maybe other bakers do.
00:00:32.960 --> 00:00:46.560
And I learned about pH from Tomas Tefri Shimblon, who I mentioned in the last episode, his class, modern bread and vinoiserie at SFBI, totally changed my life.
00:00:46.719 --> 00:00:55.759
In that class, we used pH a little bit for bread, but mostly for panetone, brioche, again, vinoiserie.
00:00:56.000 --> 00:01:03.759
And when I learned about it, I came home and I am not a person to make brioche or panettone.
00:01:03.840 --> 00:01:15.760
I tried my hand at it and it came out really well, but I was having to use a lot of shipped white flour, and in the end, it just wasn't something that ended up sticking.
00:01:16.400 --> 00:01:22.879
And I decided that I was going to give it a little rest until I could find a more ethical flour to use.
00:01:23.200 --> 00:01:32.319
But I started using pH in every single one of my bake days to feed my Levant, to divide my dough for shaping.
00:01:32.480 --> 00:01:37.680
I was just poking my pH meter in all the doughs and recording everything.
00:01:37.760 --> 00:01:40.640
And that was probably a little over three years ago now.
00:01:40.959 --> 00:01:45.359
So I've learned a lot in that time, and I'm looking forward to sharing it with you.
00:01:45.599 --> 00:01:49.040
One more sort of like housekeeping thing before we get started.
00:01:49.280 --> 00:02:03.439
If you follow me on Instagram on social media at MatriarchBread, you may have seen that I recently just announced that I will be teaching a class with Alex from Wild Woman.
00:02:03.760 --> 00:02:05.120
And she was on the podcast.
00:02:05.200 --> 00:02:06.319
She was our second guest.
00:02:06.480 --> 00:02:12.479
And another friend of mine, Lila from The Early Rise, who will eventually be on the podcast.
00:02:12.879 --> 00:02:18.159
And she was also the creator of West Coast Breadfest, which has come up quite a few times on the podcast already.
00:02:18.400 --> 00:02:28.879
If that's something you're interested in learning more about, please follow me on social media again, matriarch.bred, and there will be lots more information posted there.
00:02:29.120 --> 00:02:35.599
But I just wanted to give it a little shout out because it's a passion project and something we've been talking about for a really long time.
00:02:36.080 --> 00:02:39.840
And I won't share too much more than that here on the podcast.
00:02:39.919 --> 00:02:44.560
But just in case you wanted to find out some more, yes, please head over to my Instagram.
00:02:44.639 --> 00:02:52.000
But for today, we are going to focus on PH, Sourdough Microbiology, and we are just going to get into it.
00:02:52.080 --> 00:03:01.439
So it was a very long intro, but this is a topic that I'm really passionate about and something I look forward to diving a little bit deeper with all of you.
00:03:01.599 --> 00:03:04.800
I'm Allie White, and this is Saving Bread.
00:03:50.240 --> 00:03:58.000
But now that I've been using it for quite a few years, a little over three years, I'm not as married to it as I was initially.
00:03:58.159 --> 00:04:02.800
I've learned that there's a lot more wiggle room than I originally thought.
00:04:02.960 --> 00:04:06.479
And there's just a lot of other pieces of the puzzle.
00:04:06.719 --> 00:04:18.160
So I think what I want to do is get a little bit deeper into the microbiology of sourdough, some of the things that I've learned about what's even in a sourdough culture.
00:04:18.399 --> 00:04:23.040
And then I would like to explain to all of you how I use pH.
00:04:23.600 --> 00:04:30.079
You will never hear me claim that there's only one way to do things, or that my way is the best way.
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I consider myself at the beginning of my baking journey.
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I am very thankful for the experiences that I've had, for the people that I've learned from.
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I've had incredible mentors, wonderful people holding my hand along the way who have taught me so much.
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And I'm really, really thankful for that.
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Each one of those experiences has taught me that there is no one way to make bread.
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I have no angle here.
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I have no ego about this.
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I simply like to share what I've learned, share what I've experienced in my real life in my bakery, and wonderful things that I've also learned from others.
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Any guest that I have on, I am highlighting what they are good at, what they love to do, what they have learned.
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I think it's really important, especially what I'm hoping to cultivate in this space for saving bread is that it's not about being right.
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It's not about winning, it's not about who can make the best bread.
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It's just sharing information.
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So when I talk about this today, please know that my intention is just to share what I have experienced and what I've learned.
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And I'm always open to building upon that, learning from others, collaborating with others.
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And I really hope that when you hear this, you take away something valuable that you can add into your practice at home and take what you like and leave what you don't.
00:06:06.240 --> 00:06:17.040
Okay, so again, today I want to talk about the microbiology of sourdough, not at a level where we need to memorize organisms or biochemical pathways.
00:06:17.279 --> 00:06:27.519
I want to cover enough of the science to understand what is happening during fermentation and more importantly, how that information can make us better bakers.
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Why does dough rise?
00:06:29.839 --> 00:06:31.439
Why does the pH fall?
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Why does dough eventually begin to lose strength?
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Why does whole grain dough behave differently than a mostly white flour country loaf?
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And what information are we actually getting when we measure pH?
00:06:43.600 --> 00:06:46.800
Understanding some of this changed the way that I think about fermentation.
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Instead of asking whether a dough has fermented for the number of hours written in a formula, I'm much more interested in what actually happened inside of that dough during those hours.
00:06:58.160 --> 00:06:59.680
So let's start with the starter.
00:07:00.000 --> 00:07:02.639
What is living in a sourdough starter?
00:07:02.879 --> 00:07:09.360
A sourdough starter, or perhaps it's a lavan that you've built to go into one of your mixes.
00:07:09.600 --> 00:07:12.560
It's a mixed microbial culture.
00:07:12.879 --> 00:07:22.399
The two groups that matter the most to us as bakers are yeasts and lactic acid bacteria, usually shortened to LAB or lab.
00:07:23.839 --> 00:07:26.959
There can be many different species of both.
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You may have heard some really fancy names.
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If you want to go down those rabbit holes of what's what, I strongly encourage you to do that on your own time, but I don't think knowing the names is the important part.
00:07:38.240 --> 00:07:43.120
I don't want to lose anyone here because the science gets too complicated or too difficult to say.
00:07:43.279 --> 00:07:47.600
Studies of sourdough starters have found a lot of microbial diversity.
00:07:47.920 --> 00:07:58.800
Flower type, hydration, temperature, feeding frequency, feeding ratio, and other conditions can all influence which organisms become established.
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That's one of the reasons two healthy starters can behave differently.
00:08:03.600 --> 00:08:16.240
The important point for this episode is that a starter contains a community of microorganisms living together in an environment we create through the way we maintain it.
00:08:16.399 --> 00:08:18.160
What does the yeast do?
00:08:18.879 --> 00:08:23.279
Yeast is one of the main drivers of leavening.
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Yeasts use available sugars during fermentation and produce carbon dioxide and ethanol.
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The carbon dioxide becomes trapped within the dough's gluten network.
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As more gas accumulates, the dough will expand.
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So when we see a starter or a dough rising or increasing in volume, gas production is part of what we are observing.
00:08:55.840 --> 00:08:59.679
Some lactic acid bacteria can also produce carbon dioxide.
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So yeast is not the only possible source of gas and sourdough, but in most wheat sourdough bread systems, yeast is the main contributor to leavening.
00:09:12.720 --> 00:09:20.720
The other major product of yeast fermentation is ethanol, but most of that ethanol is lost during baking.
00:09:20.960 --> 00:09:27.679
So yeast gives us a major part of the physical rise we associate with fermentation.
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But the microorganisms need fermentable carbohydrates to do this, they need food.
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And so that brings us to our flour.
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There are enzymes in flour.
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Flour contains naturally occurring enzymes.
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One important group of enzymes is called amylase.
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Amylases act on starch.
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Starch is made from long chains of glucose molecules.
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Enzymes break those large starch molecules into smaller carbohydrates that can then become available during fermentation.
00:10:14.000 --> 00:10:18.639
Two terms that you may hear are alpha amylase and beta amylase.
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They act on starch differently.
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Alpha amylase breaks starch chains internally and produces smaller starch fragments, including dextrins.
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And then beta amylase works from the ends of starch chains and releases maltose.
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You don't really need to remember any of those specific mechanisms.
00:10:37.039 --> 00:10:39.919
The useful part for the baker is this.
00:10:40.399 --> 00:10:43.360
We start with the starch in the flour.
00:10:43.679 --> 00:10:47.440
Enzymes break some of that starch into smaller carbohydrates.
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This happens as soon as the water is added to the flour.
00:10:50.960 --> 00:10:58.159
Those carbohydrates become available to yeast and bacteria, and the microorganisms then ferment them.
00:10:58.720 --> 00:11:03.519
So fermentation is not just yeast being added to flour and producing gas.
00:11:03.600 --> 00:11:14.960
There's already enzyme activity taking place inside of the dough with the flour and the water that affects the carbohydrates available to the microorganisms.
00:11:15.840 --> 00:11:20.879
Lactic acid bacteria are the other major group in sourdough starter.
00:11:21.759 --> 00:11:26.639
Lab use carbohydrates and produce organic acids.
00:11:27.200 --> 00:11:35.200
Lactic acid is one major product of all of this, depending on the species and fermentation pathway.
00:11:35.440 --> 00:11:41.679
They may also produce acetic acid, carbon dioxide, ethanol, and a number of other compounds.
00:11:41.840 --> 00:11:48.080
These organisms are a major reason that sourdough becomes acidic.
00:11:48.559 --> 00:11:50.799
It has that tangy flavor.
00:11:51.039 --> 00:11:57.440
As organic acids accumulate during fermentation, the pH generally begins to fall.
00:11:58.159 --> 00:12:08.799
The acids and other metabolites produced during fermentation also contribute to the flavor and the aroma of sourdough bread, that signature tang.
00:12:09.200 --> 00:12:13.519
This is where yeast and bacteria need to be thought about together.
00:12:13.679 --> 00:12:22.399
They are not doing identical jobs, but they are living in the same fermentation environment and affecting that environment at the same time.
00:12:22.559 --> 00:12:33.679
So temperature matters, flour matters, hydration matters, how often you feed your starter matters, the amount of starter you carry into the next feeding matters.
00:12:33.759 --> 00:12:39.519
All of these variables can influence fermentation and over time the microbial community itself.
00:12:39.840 --> 00:12:47.919
That is the one reason I think consistency is just so important when you're learning your starter's behavior.
00:12:48.080 --> 00:12:56.799
If you change several variables every single day, it becomes very difficult to understand why the starter has behaved differently.
00:12:56.960 --> 00:12:58.559
So let's talk about pH.
00:12:58.879 --> 00:13:05.200
I use pH frequently in my baking, but pH is one measurement of fermentation.
00:13:05.279 --> 00:13:07.919
It is not fermentation itself.
00:13:08.159 --> 00:13:09.919
That distinction is really important.
00:13:10.080 --> 00:13:11.519
I'm still looking at the dough.
00:13:11.679 --> 00:13:13.440
I look at the amount of expansion.
00:13:13.519 --> 00:13:17.840
I look at the bubbles, I feel the strength and extensibility.
00:13:19.919 --> 00:13:22.559
I take into consideration the dough temperature.
00:13:22.799 --> 00:13:30.960
I'm thinking about which flowers I used for my mix, and I use pH as another piece of information.
00:13:31.440 --> 00:13:33.279
So what does pH even mean?
00:13:33.440 --> 00:13:38.320
The pH scale runs from zero all the way to 14.
00:13:38.799 --> 00:13:40.799
7 is neutral.
00:13:41.279 --> 00:13:47.519
Numbers below 7 are considered acidic, and numbers above 7 are called alkaline.
00:13:47.600 --> 00:13:58.720
For our purposes, that means the difference between something at pH 5 and something at pH 4 is much greater than the numbers make it appear.
00:13:58.960 --> 00:14:06.159
During sourdough fermentation, organic acids accumulate and pH generally falls.
00:14:06.639 --> 00:14:18.559
A freshly mixed bread dough might begin somewhere in the mid-fives or higher, 5.5, maybe 5.6, depending on the flour, the lavan, and the formula.
00:14:18.639 --> 00:14:33.200
If we're talking about the same country dough, the same one that we've been using since the beginning of the podcast, with about 20% whole grain and the rest is white flour, you can expect the pH to begin somewhere around 5.5 or 5.6 once the lavan has been added.
00:14:33.360 --> 00:14:37.200
As the fermentation continues, that number will decrease.
00:14:37.360 --> 00:14:40.080
It will become lower and lower with time.
00:14:40.320 --> 00:14:52.960
If my dough begins around 5.5 and later reaches 4.8, I now have measurable evidence that acidification has occurred.
00:14:53.279 --> 00:14:59.519
But pH does not tell us the entire story of acidity, and that becomes especially important with whole grain.
00:14:59.600 --> 00:15:02.639
So let's talk about pH versus total acidity.
00:15:02.879 --> 00:15:10.720
You may hear another measurement called TTA or total titratable acidity.
00:15:11.120 --> 00:15:17.759
I do not think most bakers need to measure TTA at home, but it helps to understand what it represents.
00:15:18.240 --> 00:15:24.240
So pH tells us about the hydrogen ion activity in the dough.
00:15:24.559 --> 00:15:30.159
TTA is measured by adding a base to a sample until a defined endpoint is reached.
00:15:30.480 --> 00:15:38.240
The amount of base required gives us information about the titratable acids and the buffering system in that dough.
00:15:38.320 --> 00:15:39.120
These are big words.
00:15:39.279 --> 00:15:40.159
Don't get lost.
00:15:40.240 --> 00:15:44.480
I just need to get through this part so you can understand the limitations of pH.
00:15:44.639 --> 00:15:48.639
So pH and TTA are related, but they are not interchangeable.
00:15:48.879 --> 00:15:55.039
Two doughs can have similar pH readings and still have a different titratable acidity.
00:15:55.200 --> 00:15:57.279
This is especially relevant with whole grain.
00:15:57.519 --> 00:16:04.159
Whole grain flour generally has a greater buffering capacity than refined flour.
00:16:04.399 --> 00:16:11.360
That is partly related to the greater amount of minerals and other compounds present in the outer portion of the grain.
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A more highly buffered dough can accumulate more acid without showing the same change in pH that we might see in a less buffered dough.
00:16:25.440 --> 00:16:29.840
This is one of the reasons I'm careful about treating pH targets as universal numbers.
00:16:30.000 --> 00:16:33.200
The flower really matters.
00:16:34.000 --> 00:16:38.720
Let's talk about a young versus a mature Levan.
00:16:40.080 --> 00:16:44.799
This is another area where I think the language can become too rigid.
00:16:45.279 --> 00:16:51.840
I sometimes use pH as part of the way that I evaluate the maturity of a lavan.
00:16:52.080 --> 00:17:00.240
In my own baking, I often like to use a lavan somewhere around pH 4.0 to 4.2.
00:17:00.480 --> 00:17:06.640
This is a range that works well for many of my doughs and for the way that I maintain my lavan.
00:17:06.880 --> 00:17:15.599
If I allow the lavan to ferment longer and become more acidic, I may see it drop into the high threes.
00:17:16.400 --> 00:17:24.160
But there is not one pH number where a lavan suddenly changes from young to mature or where the yeast suddenly stops working.
00:17:24.319 --> 00:17:27.599
As the lavan continues fermenting, several things happen.
00:17:27.839 --> 00:17:37.839
Sugars and other nutrients are being consumed, acids are accumulating, the environment is becoming more acidic, and microbial metabolism is changing.
00:17:37.920 --> 00:17:41.440
And eventually the structure of the lavan itself can weaken.
00:17:41.599 --> 00:17:44.960
So I look at pH along with the rest of the lavan.
00:17:45.119 --> 00:17:46.480
How long is it fermented?
00:17:46.640 --> 00:17:48.559
What temperature was it held at?
00:17:48.720 --> 00:17:50.319
How much has it risen?
00:17:50.559 --> 00:17:52.000
What does it smell like?
00:17:52.160 --> 00:17:53.839
What does the structure look like?
00:17:54.000 --> 00:17:57.039
And what kind of dough am I planning to put it into?
00:17:57.279 --> 00:18:05.359
The Levan I want for one bread may not be exactly the same lavan I want for another.
00:18:05.599 --> 00:18:12.880
I want to pause here and say, I use the Hannah bread and dough pH meter.
00:18:13.119 --> 00:18:18.160
I have the Bluetooth version and I have the one that doesn't have Bluetooth.
00:18:18.319 --> 00:18:20.319
They work very similarly, in my opinion.
00:18:20.480 --> 00:18:22.559
I enjoy using both of them.
00:18:23.039 --> 00:18:42.720
Most meters, specifically that meter, because of the acids that are in the dough, as the hydrogen starts to accumulate, as the acidity begins to build, those meters cannot read below, I believe it's 3.9.
00:18:43.279 --> 00:18:53.599
So if you stick a pH meter in your dough and you're getting a reading of 3.8, it's basically impossible to have an accurate reading at that point.
00:18:53.920 --> 00:19:01.039
I personally only trust any readings that I get from my pH meter between 3.9 and higher.
00:19:01.279 --> 00:19:04.160
So I just wanted to pause there and say that.
00:19:04.319 --> 00:19:16.240
But this is very convenient because typically, as you'll learn as the podcast goes along, I don't like to let either my Levant or my dough drop below pH 4.0.
00:19:16.559 --> 00:19:27.359
But I do think it's important to understand that if you do purchase a meter, any of the readings that come from it can really only be trusted from, in my experience, 3.9 and higher.
00:19:27.599 --> 00:19:27.920
Okay?
00:19:28.720 --> 00:19:29.839
Let's get back to it.
00:19:29.920 --> 00:19:32.799
Let's talk about protease and dough strength.
00:19:32.960 --> 00:19:40.319
There's another group of enzymes worth talking about because it helps explain what happens to dough during a long fermentation.
00:19:40.799 --> 00:19:46.799
Proteases break proteins into smaller peptides and amino acids.
00:19:47.119 --> 00:19:50.799
Wheat flour contains its own proteolytic enzymes.
00:19:51.039 --> 00:19:56.799
The microorganisms in sourdough also contribute to protein and peptide metabolism.
00:19:57.119 --> 00:20:09.279
As sourdough becomes more acidic, as the dough becomes more acidic and the pH begins to drop, some of the cereal proteases in that dough become more active.
00:20:09.519 --> 00:20:14.240
Research commonly describes significant cereal protease activity.
00:20:14.319 --> 00:20:27.039
Once sourdough becomes fairly acidic, especially below roughly pH 4.5, some protein breakdown is definitely a normal part of fermentation.
00:20:27.119 --> 00:20:35.039
It contributes to the pool of peptides and amino acids in the dough, which can also contribute to flavor development.
00:20:35.359 --> 00:20:43.279
But if fermentation continues too far, the dough can eventually lose strength.
00:20:43.440 --> 00:20:44.720
You already recognize this.
00:20:44.880 --> 00:20:57.759
All bakers already know this intuitively because the dough becomes increasingly slack, it becomes sticky, it spreads more easily, it becomes difficult to build tension during shaping.
00:20:58.079 --> 00:21:17.279
That loss of structure is not caused by one enzyme alone: acidification, proteolysis, fermentation time, flower strength, hydration, temperature, and mechanical handling all play a role.
00:21:17.680 --> 00:21:22.640
So I would not look at a weak dough and say, uh, protease did this.
00:21:22.960 --> 00:21:40.960
If you turn your dough out and it just flops into a pancake after it's been in the fridge all night, it's not just the work of one enzyme, but protein breakdown is part of the larger process occurring as a dough ferments and acidifies.
00:21:41.119 --> 00:21:43.680
This is why fermentation is a balance.
00:21:43.839 --> 00:21:56.640
We need enough fermentation to produce gas, flavor, and the dough characteristics that we want, but we also need the dough to retain enough structure to hold that gas.
00:21:56.799 --> 00:21:59.759
It's a game, it is a balancing act and it.
00:22:00.240 --> 00:22:01.279
Takes a lot of practice.
00:22:01.359 --> 00:22:03.359
So, how do I apply this to my country dough?
00:22:03.440 --> 00:22:07.680
So, I want to bring out all of this microbiology and put it into actual bread.
00:22:07.759 --> 00:22:17.200
So, for my country dough, the one that we've been talking about since the beginning of the podcast, 20% whole grain, 20% lavan, 10% prefermented flour.
00:22:17.359 --> 00:22:22.799
The exact formula maybe changes a little bit, but the fermentation pattern is fairly consistent.
00:22:22.960 --> 00:22:33.279
After mixing, the dough will likely rise into a pH range of the mid-5s, 5.5, 5.4, somewhere around there.
00:22:33.519 --> 00:22:35.519
Then bulk fermentation begins.
00:22:35.599 --> 00:22:38.720
You've added your Levan to your dough, the pH has risen.
00:22:38.880 --> 00:22:41.680
We have entered the beginning of bulk fermentation.
00:22:41.920 --> 00:22:45.039
Dough temperature is a major variable.
00:22:45.279 --> 00:22:56.559
Remember, for my country dough, I generally work with a desired dough temperature, somewhere around 77 to 82 degrees Fahrenheit, really depending on the time of year and my production schedule.
00:22:56.799 --> 00:23:02.480
Bulk fermentation might take somewhere around three to four hours in my system.
00:23:02.880 --> 00:23:08.559
But the important point is that three hours does not automatically mean that the dough is finished, right?
00:23:08.720 --> 00:23:16.240
We're looking at the dough, we're using temperature, we're using time, we're using pH all together.
00:23:16.960 --> 00:23:24.480
As fermentation progresses, I watch the dough expand and develop while the pH falls.
00:23:24.799 --> 00:23:32.559
For my current country dough, I may divide somewhere around pH 4.7 to 4.6.
00:23:32.799 --> 00:23:36.960
That number is in no way a universal recommendation.
00:23:37.039 --> 00:23:41.759
I am telling you what I do in my system in production.
00:23:42.400 --> 00:23:50.559
This is a target I've developed using my exact flour, my lavan, my inoculation, my temperatures, everything.
00:23:51.440 --> 00:23:55.519
After dividing, I still have fermentation ahead of me.
00:23:55.680 --> 00:24:03.920
Depending on the dough, I may pre-shape, allow it to rest, final shape, and give it additional time in the banner in the basket.
00:24:04.160 --> 00:24:10.160
But typically, I want to get my dough into the fridge around 4.3.
00:24:10.480 --> 00:24:14.720
That's what works for my refrigerator that I keep at 36 degrees Fahrenheit.
00:24:14.880 --> 00:24:18.720
So if you remember, we started bulk fermentation in the mid-fives.
00:24:18.880 --> 00:24:24.559
We allowed the pH to drop to around 4.7, maybe 4.6.
00:24:24.799 --> 00:24:39.119
We've divided the dough, and in that time I need to divide, pre-shape, let it rest, final shape, and have some time in the basket and get it into the refrigerator around 4.3, sometimes 4.2.
00:24:39.279 --> 00:24:41.839
That is what works with my system.
00:24:42.640 --> 00:24:46.480
I'm looking at how much time I have, where does that dough need to go?
00:24:46.640 --> 00:24:56.480
What are all the steps, knowing that I need to get into the fridge by a specific endpoint, and it helps me manage my time for my dough for that production day.
00:24:56.720 --> 00:25:00.799
The pH will continue to drop during the cold retard.
00:25:01.039 --> 00:25:13.039
By the time I take my dough out of the fridge the next day, approximately 12 to 18 hours later, typically my dough has come all the way down to pH 4.0 or 4.1.
00:25:13.119 --> 00:25:18.720
Again, those are my numbers in my experience in my home with my dough.
00:25:18.960 --> 00:25:26.319
What makes them useful is that I repeat the process every single time.
00:25:26.960 --> 00:25:34.640
I have all of my checkpoints that I repeat so that I can bake consistently from week to week to week.
00:25:34.799 --> 00:25:39.119
Your numbers may be different than mine, and that is okay.
00:25:40.079 --> 00:25:58.559
The point isn't to copy my system, it's to know your own system, have measurements that you take along the way, time, temperature, flower, pH, and repeat your system at home week after week after week, especially if you're in production.
00:25:58.720 --> 00:26:01.759
The refrigerator does not stop fermentation immediately.
00:26:01.839 --> 00:26:15.680
So this is a really important part of my process, especially during the summer when it's hot and like the dough is hot, the mixer's hot, the flour's hot, everything's hot, the water's coming out of the tap hot, like it's hard to manage, right?
00:26:16.079 --> 00:26:17.279
This is an important part.
00:26:17.440 --> 00:26:18.880
This is an important piece of the puzzle.
00:26:19.039 --> 00:26:28.880
When the dough goes into the refrigerator, fermentation slows as the dough cools, but it doesn't stop the instant the basket enters the refrigerator.
00:26:29.039 --> 00:26:38.000
A warm loaf has to lose that heat and the center of the dough, specifically like right through the middle, it takes time to cool down.
00:26:38.079 --> 00:26:41.200
And it honestly will probably never get to fridge temp.
00:26:41.279 --> 00:26:48.720
It's always going to be a couple of degrees warmer, especially if you have a ton of dough in the fridge or you're opening and closing the fridge for other purposes.
00:26:48.960 --> 00:26:59.039
So, how quickly that happens really depends on the refrigerator temperature, airflow, dough size, again, how much warm dough is loaded into the fridge at one time.
00:26:59.200 --> 00:27:02.079
So this really matters in bakery production.
00:27:02.240 --> 00:27:10.559
Putting one loaf in a cold refrigerator is totally different from loading a refrigerator with dozens of warm loaves.
00:27:10.799 --> 00:27:21.359
So when I choose the point where the loaf goes into the cold retard, I am accounting for the fermentation that will continue while the dough cools.
00:27:21.519 --> 00:27:25.440
Some days that might take a lot longer than other days.
00:27:25.599 --> 00:27:33.440
Seasonality, time of year, outdoor temperature, all these things, like your fridge works so hard in the summer to keep things cool.
00:27:33.599 --> 00:27:39.039
You really need to think about all of these things and decide: does this dough need to go in sooner?
00:27:39.279 --> 00:27:41.279
Can it go in a little bit later?
00:27:41.519 --> 00:27:46.400
These are the decisions that seasoned bakers are making every single bake day.
00:27:46.799 --> 00:27:54.480
So, what changes when we move from a standard country dough to a dough with a high amount of whole grain?
00:27:54.720 --> 00:27:59.519
Because I approach high whole grain dough completely differently.
00:27:59.759 --> 00:28:04.720
Whole grain introduces the bran and the germ along with the endosperm.
00:28:05.039 --> 00:28:12.319
Bran changes the physical behavior of the dough and can interfere with the development and continuity of the gluten network.
00:28:12.559 --> 00:28:20.880
Whole grain flour also contains more minerals and other compounds and generally has greater buffering capacity, which we talked about earlier.
00:28:20.960 --> 00:28:26.319
It can be harder to get an accurate reading of how much acid is actually in that dough.
00:28:26.480 --> 00:28:34.160
You have to be an intuitive baker in some ways when you start working with more whole grains because you cannot rely on data alone.
00:28:34.319 --> 00:28:39.279
Its enzyme activity and fermentation behavior can also differ from refined flour.
00:28:39.440 --> 00:28:48.480
So I do not assume that my country low fermentation targets should transfer directly to a dough containing 50, 80, or even 100% whole grain.
00:28:48.559 --> 00:28:56.160
For a dough with 50% whole grain or more, to give myself a little bit more wiggle room.
00:29:01.920 --> 00:29:08.720
Whereas with my country dough, I can allow it to come down a little bit more, closer to pH 4.1, 4.0.
00:29:09.119 --> 00:29:13.119
But I do like a tiny bit of wiggle room for the whole grain.
00:29:13.200 --> 00:29:15.039
But again, it's a range.
00:29:15.119 --> 00:29:17.440
You will figure out what works for your system.
00:29:17.920 --> 00:29:27.359
My desired dough temperature for my whole grain loaves typically is around 80 degrees, and bulk in my production system takes around three hours.
00:29:27.759 --> 00:29:32.559
But I typically divide that dough much earlier in terms of acidification.
00:29:32.640 --> 00:29:41.039
So closer to pH 5.0, maybe 4.9, depending on what I'm doing after that.
00:29:41.279 --> 00:29:51.200
If I want to pre-shape, bench rest, final shape, basket proof, I typically need to divide on the earlier side, around 5.0.
00:29:51.599 --> 00:29:58.799
If I'm skipping the pre-shape, which sometimes happens when things are moving quickly, the dough might come down to around 4.8.
00:29:58.960 --> 00:30:02.480
At that point, I'm completely skipping the divide and pre-shape.
00:30:02.559 --> 00:30:09.119
I'm going directly to the final shape, directly in the basket, a short basket rest, and then I'm into the fridge.
00:30:09.440 --> 00:30:16.799
No matter what, like hell or high water for whole grain doughs, I am in my refrigerator at pH 4.7.
00:30:17.920 --> 00:30:27.599
Getting in that early the next day, when I come back to my dough from the fridge, I'm coming out around 4.3-ish, 4.4.
00:30:27.759 --> 00:30:33.599
There is a pretty big drop that happens with whole grain dough in the cold retard.
00:30:33.759 --> 00:30:38.319
So those numbers are intentionally higher than the numbers I use with my country loaf.
00:30:38.400 --> 00:30:44.960
I'm working with a dough that has different flour composition, different buffering capacity, and different structural limitations.
00:30:45.119 --> 00:30:50.480
There are, gosh, so many ways to make an excellent whole grain bread.
00:30:50.640 --> 00:30:55.440
These are the numbers that work for me within my process.
00:30:55.599 --> 00:31:13.519
So rather than asking what is the correct pH for bread, I think it's more useful to think about it as what pH corresponds with the fermentation I want when I use this flour, this formula, this temperature, and this process.
00:31:13.839 --> 00:31:17.599
That gives that number context, okay?
00:31:17.839 --> 00:31:20.000
Flour changes the fermentation environment.
00:31:20.160 --> 00:31:22.960
This is another reason I think flour selection matters so much.
00:31:23.119 --> 00:31:27.279
When we change the flour, we are changing more than just the protein percentage.
00:31:27.440 --> 00:31:37.279
Different flowers bring different amounts of minerals, enzymes, damaged starch, nutrients, and microorganisms into the dough.
00:31:37.519 --> 00:31:43.279
Whole grain includes parts of the kernel that have been removed for refined flour.
00:31:43.359 --> 00:31:48.160
So changing the flour absolutely changes fermentation behavior.
00:31:48.319 --> 00:31:53.039
This is why a whole grain starter may behave differently from a white flour starter.
00:31:53.200 --> 00:32:01.680
And it is why when someone is trying to understand their starter, I recommend keeping the maintenance routine fairly consistent for a while.
00:32:01.920 --> 00:32:07.759
Use the same flour, use the same feeding ratio, try to keep the temperature consistent.
00:32:08.079 --> 00:32:10.960
Observe how long it takes to rise.
00:32:11.200 --> 00:32:14.240
Pay attention to the aroma and the structure.
00:32:14.400 --> 00:32:15.519
Maybe taste it.
00:32:15.759 --> 00:32:24.000
Measure the pH if that's a tool that you want to use, and then change one variable and see what happens.
00:32:24.240 --> 00:32:27.599
That gives you useful information.
00:32:27.759 --> 00:32:30.880
Let's talk about a question I am asked frequently.
00:32:31.039 --> 00:32:34.640
Does a lower pH mean a more sour loaf?
00:32:34.799 --> 00:32:36.240
Not necessarily.
00:32:36.640 --> 00:32:41.519
pH and perceived sourness are related, but it's not the same thing.
00:32:41.680 --> 00:32:46.880
Sourdough contains multiple organic acids and many other flavor compounds.
00:32:47.119 --> 00:32:52.640
Lactic acid and acetic acid also have different sensory qualities.
00:32:52.960 --> 00:33:00.000
pH alone does not tell you exactly how much of each acid is present, although it'd be really cool if it did.
00:33:00.240 --> 00:33:06.319
It also does not tell you how sour a person will perceive the bread to be.
00:33:06.559 --> 00:33:12.559
So two loaves with a similar pH measurement may still taste different.
00:33:12.799 --> 00:33:20.319
This is another reason to treat pH as one measurement instead of using it as a complete description of the bread.
00:33:20.880 --> 00:33:22.960
Does sourdough break down gluten?
00:33:23.279 --> 00:33:28.480
This is another area where I get a lot of questions, and I think we should be very thoughtful about our language.
00:33:28.720 --> 00:33:33.119
Protein breakdown does occur during sourdough fermentation.
00:33:33.359 --> 00:33:34.079
Absolutely.
00:33:34.400 --> 00:33:41.519
Acidification activates cereal proteases, and microorganisms also participate in peptide metabolism.
00:33:41.839 --> 00:33:51.279
So the protein structure of a fermented dough is not exactly the same as it was immediately after mixing.
00:33:51.519 --> 00:33:58.000
Normal sourdough fermentation does not make ordinary wheat bread gluten-free.
00:33:58.079 --> 00:34:00.079
And we should never claim that it does.
00:34:00.640 --> 00:34:14.639
Regular sourdough wheat bread should not be considered a safe food for someone with celiac disease unless it meets the specific standards required for a gluten-free food.
00:34:14.880 --> 00:34:19.280
I don't know what it is, but it's like some parts per million or parts per billion.
00:34:19.440 --> 00:34:21.760
You would have to get that food item tested.
00:34:21.920 --> 00:34:25.360
We cannot make these health claims as bakers.
00:34:25.440 --> 00:34:32.960
So please be responsible with the words that you choose when you are marketing and selling your bread to the community.
00:34:33.440 --> 00:34:49.119
There has been research using specific microorganisms and carefully controlled fermentation processes to achieve extensive gluten degradation, but that is very different from making a normal loaf of sourdough at home or in a bakery.
00:34:49.199 --> 00:34:57.840
So I think it's accurate to say that sourdough fermentation modifies and partially breaks down grain proteins.
00:34:57.920 --> 00:35:08.960
But I would not describe standard sourdough bread as gluten-free or make any broad claims that it's automatically easier for anyone to digest.
00:35:09.840 --> 00:35:12.559
So what's actually happening during fermentation?
00:35:12.800 --> 00:35:19.440
When we mix flour, water, salt, and lavan, several processes are happening at the same time.
00:35:19.679 --> 00:35:23.039
Enzymes in the flour are acting on starches and proteins.
00:35:23.199 --> 00:35:27.760
Yeasts are fermenting available sugars and producing carbon dioxide and ethanol.
00:35:28.000 --> 00:35:34.400
Lactic acid bacteria are metabolizing carbohydrates and producing organic acids and other compounds.
00:35:34.639 --> 00:35:36.400
The pH is falling.
00:35:36.639 --> 00:35:38.559
Gas is accumulating.
00:35:38.800 --> 00:35:41.599
The dough structure is changing.
00:35:41.840 --> 00:35:44.239
The profile is developing.
00:35:44.480 --> 00:35:51.840
None of these processes happen in isolation and they do not all move at the exact same rate.
00:35:52.000 --> 00:36:01.039
That's why temperature has such a huge effect on bread, and it's why flour has such a large effect and why hydration can change the way fermentation behaves.
00:36:01.199 --> 00:36:06.239
And it's why fermentation cannot be completely described with a clock.
00:36:06.400 --> 00:36:09.199
Here's what I want bakers to take away from this chat today.
00:36:09.519 --> 00:36:15.679
You do not need to understand every organism in your starter to make good bread.
00:36:15.840 --> 00:36:18.719
You also don't need a pH meter.
00:36:18.960 --> 00:36:34.400
What I find useful about understanding the science is that it gives context to the things we already observe in the real world with our eyes, with our nose, with our ears, and it gives context to our senses.
00:36:34.559 --> 00:36:38.480
If the dough is rising, gas is probably being produced and retained.
00:36:38.639 --> 00:36:45.920
If the pH is falling or the dough is tasting and smelling more sour, acidification is occurring.
00:36:46.239 --> 00:36:58.480
If the dough becomes increasingly extensible or eventually begins losing strength, biochemical and physical changes have been occurring throughout fermentation.
00:36:59.119 --> 00:37:02.559
The goal is to connect those observations.
00:37:03.119 --> 00:37:05.039
Look at what's in front of you.
00:37:05.199 --> 00:37:16.480
Look at the dough, touch it, pay attention to your temperature, watch its expansion, notice how the surface changes.
00:37:17.119 --> 00:37:18.079
Smell it.
00:37:18.239 --> 00:37:22.320
And if you use a pH meter, record that information too.
00:37:22.880 --> 00:37:25.679
Then look at the bread that you baked.
00:37:26.239 --> 00:37:28.800
That's where all this information becomes useful.
00:37:28.960 --> 00:37:40.480
If I consistently divide a dough at pH 4.7 and I like the bread that comes from it, that number becomes meaningful within my process.
00:37:41.199 --> 00:37:49.840
If I change the flour and suddenly the same target gives me a very different loaf, that tells me I need to reconsider the target.
00:37:50.159 --> 00:38:05.760
If my whole grain dough consistently loses strength before reaching the same pH as my country dough, I should not keep pushing it just because I have decided that one particular number means fermentation is finished.
00:38:05.840 --> 00:38:07.760
That is not how it works.
00:38:08.000 --> 00:38:10.639
That is the way I use pH.
00:38:10.719 --> 00:38:13.280
It helps me document what the dough is doing.
00:38:13.360 --> 00:38:22.960
It helps me repeat results and it helps me identify what changed when a bake does not go the way that I expected it to.
00:38:23.119 --> 00:38:29.039
The number is most useful when it is actually connected to the dough that is physically in front of you.
00:38:29.199 --> 00:38:33.599
And I think that is really the point of understanding the microbiology.
00:38:33.760 --> 00:38:40.000
We do not need the science to make bread more complicated.
00:38:40.239 --> 00:38:45.119
We can go there, you can go there, but we don't need to go there.
00:38:45.280 --> 00:38:48.320
We use it to better understand what we're already seeing.
00:38:48.559 --> 00:38:50.960
Yeast and bacteria are fermenting the dough.
00:38:51.199 --> 00:38:57.039
Flour enzymes are helping make nutrients available and changing the dough along the way.
00:38:57.519 --> 00:39:01.199
Organic acids are accumulating and pH is falling.
00:39:01.440 --> 00:39:05.119
The structure is developing and eventually it will begin to weaken.
00:39:05.280 --> 00:39:14.400
And our job as bakers is to decide when that dough has reached the point that we want.
00:39:14.719 --> 00:39:27.039
That decision comes from the combination of time, temperature, flour, feel, visual cues, most importantly, experience.
00:39:27.519 --> 00:39:30.480
And if you choose to use it, pH.
00:39:30.880 --> 00:39:40.480
The more of those pieces that we understand, the easier it becomes to build a fermentation process that works consistently for the bread we actually want to make.
00:39:41.519 --> 00:39:44.880
I think that's more than enough information for today.
00:39:45.360 --> 00:39:48.719
I want to just remind you some of my key points.
00:39:49.119 --> 00:39:55.119
I typically like to work within a pH range of 4.0 to 5.5.
00:39:55.519 --> 00:39:59.920
That gives me the end and the beginning.
00:40:00.159 --> 00:40:02.880
The beginning is I mix a Levan or a dough.
00:40:02.960 --> 00:40:06.159
That pH rises all the way up into the mid-fives.
00:40:06.400 --> 00:40:12.400
And through time, it drops all the way down to pH around 4.0.
00:40:12.559 --> 00:40:17.840
Whether I'm working with Levan or dough, I will not let my pH drop below that number.
00:40:18.079 --> 00:40:24.159
If I'm feeding my starter, I'm making sure to catch it between 4.0, 4.1.
00:40:25.039 --> 00:40:29.760
If I'm baking, I really want to get into the oven between 4.0 and 4.1.
00:40:29.920 --> 00:40:38.400
You will learn that there's a pattern to these numbers and something I can't really explain, but it's just consistencies that I've noticed over time.
00:40:38.559 --> 00:40:43.760
So if you decide to begin playing with the pH meter, I would love to hear about your experience.
00:40:43.920 --> 00:40:45.199
I'm always learning.
00:40:45.280 --> 00:40:47.360
I'm always open to new ideas.
00:40:47.599 --> 00:40:54.480
I'm not saying this is the one right way, but I have been recording all of my pH measurements for quite a few years now.
00:40:54.559 --> 00:40:56.639
And I've I've really enjoyed the process.
00:40:56.719 --> 00:40:57.760
It's fun for me.
00:40:57.920 --> 00:40:58.880
I like information.
00:40:59.039 --> 00:41:12.400
I like data, but I've also learned that repetition and um leaning into your senses and taking a happy heart and a happy spirit into the bakery is equally as important.
00:41:12.639 --> 00:41:16.800
So try not to close yourself off to any part of that.
00:41:16.960 --> 00:41:20.320
Allow yourself to experience all the different ways to make bread.
00:41:20.559 --> 00:41:24.719
And again, take the parts that you love and leave the ones that you don't.
00:41:24.960 --> 00:41:27.840
So I hope you learned a few things today.
00:41:28.000 --> 00:41:34.400
If you want to send me a message on Instagram or shoot me a message through BuzzSprout, I would love to hear from you.
00:41:34.559 --> 00:41:43.840
If you've been enjoying the podcast, if you could take just a couple of minutes now to leave us a review on Spotify or Apple Podcasts, it would really mean the world to me.
00:41:44.159 --> 00:41:48.559
And I have a lot of really fun things that I'm working on behind the scenes.
00:41:48.639 --> 00:41:51.599
And some of them are specifically for you, the listeners.
00:41:51.840 --> 00:41:55.599
So stay tuned, keep listening, keep sharing.
00:41:55.760 --> 00:42:03.920
And next week, I'll be back with an interviews episode with two people who I know you'll be very excited to hear from.
00:42:04.079 --> 00:42:05.599
That's it for today, friends.
00:42:05.920 --> 00:42:06.559
Bye.
00:42:07.920 --> 00:42:11.440
Thank you for listening to the Saving Bread Podcast.
00:42:14.159 --> 00:42:17.519
Music by Joshua from Dope.
00:42:19.760 --> 00:42:21.360
I'm Allie White.
00:42:22.079 --> 00:42:26.800
And as always, happy baking and long live real bread.
