NEW!: How to Strengthen a Weak, ACIDIC Starter (A Barnyard Tragedy)

[Music] hi I'm Tom coming to you from The International Institute for the advancement of sourdo science and research of Cleveland Ohio also known as my kitchen thank you for selecting this video in today's video we're going to talk about a problem that plagues the sourdough Bakers from time to time and that is the problem of a weak star and what happens a lot of times is you'll be baking sourdough bread your starter is working perfectly fine and then over time you'll see that it just starts Rising more slowly it doesn't produce the same open Airy loaves that you were getting in the past and your starter begins to weaken this is particularly a problem for home Bakers and especially home Bakers who don't bake very frequently I've done a lot of research on this topic and I'm going to talk about what causes that but the main reason that your starter will become weak is that it becomes acidic your starter contains yeast and lactic acid bacteria and when that lactic acid bacteria starts to outrun the yeast it will build up a residual Baseline acidity over time and when your starter becomes acidic it chokes off the yeast and your yeast will not produce the same tall Airy fast rising loaves that you're used to now a lot of people see this and they describe what they have as a weak starter but really what it is is an acidic starter so in today's video I'm going to show you how to identify if your starter is acidic we'll talk a little bit about the science behind it and then I'll give you some instructions for how to fix it so before we get started let's just talk about what I Define as a strong starter versus a weak acidic starter these are the criteria that I use the first one is the rising time a strong starter with low acidity will typically rise and peak in about 4 to 6 hours after a 111 feeding at 74° fhe or 23° C room temperature a weak acidic starter will take much longer than that to rise and Peak that's typically the first giveaway that your starter is weak or acidic is that it's not rising and peaking as quickly as it has in the past the second thing I look at is the smell a strong starter with low acidity will smell yeasty and fresh a weak starter with high acidity will smell like cider vinegar that is one of the telltale signs of an acidic starter it will smell just like vinegar if you don't trust your nose you can use a pH meter or a pH tester I have a video where I review these devices this is the Hannah Halo 2 and the APPA Zen these are the two pH testers I recommend if you're going to buy one of these buy one of these lab quality testers the inexpensive pH testers you'll find on the internet really don't work but you can use a pH tester to test the acidity of your starter and a strong starter with low acidity will typically Peak at a pH of around 4.1 or 4.2 that's a relatively low acidity a very acidic starter will Peak at a pH of 3.7 to 3.8 that would be a very acidic starter the next thing I look at is how long does your starter maintain its volume after it Peaks so a strong starter with low acidity will Peak and then it will remain at that Peak for a long time before it falls a weak acidic starter will immediately fall after it Peaks and it'll fall very quickly then I look at the texture of your starter a strong starter with low acidity will be thick fluffy stringy and ropey with big bubbles in it and a weak acidic starter will typically be thin runny and have very small bubbles on top you can typically pour a weak starter out of of your jar the next thing I look at is how quickly your starter can rise your dough and bulk fermentation a strong starter with low acidity can rise your dough very quickly and a weak acidic starter will rise your dough in bulk fermentation very slowly and it may often stall out and stop Rising before it actually hits your target percentage rise the next thing I look at is what I call the gluten friendliness of your starter and what I mean by this is a low acidity strong starter will basically ferment your dough through bulk fermentation and all the way through final proofing and create a tall Airy ball of dough a weak acidic starter will start breaking down the gluten prematurely and you'll start to see your dough flattening sometimes in bulk fermentation and in final proofing because that acidity in your starter prematurely deteriorates the gluten structure and it creates those flat early over proofing Loaves and lastly you want to to look at your Loaf a strong starter with low acidity will create an open Airy beautiful crumb a weak starter with high acidity will create a dense gummy crumb so we typically use these terms strong starter versus weak starter but I'm telling you a weak starter is always an acidic starter and that's what we'll focus on in this video how to identify an acidic starter and how to fix it here are the eight criteria on one page if you'd like to pause here and review these in more detail there's also a printable document and guide in the description of this video and on my website so before I create each one of these videos I always go out and do research to see what professional Bakers have to say about this topic I have a stack of sourdough baking books this tall and you're probably asking the same question question I asked when I started to research this and that is never even heard of this before why doesn't anybody talk about anesthetic starter you can read dozens of sourdough books nobody talks about your starter being acidic and that acidity can cause all of these problems why is that the reason is because a lot of the most popular sourdough baking books were written by professional Bakers Chad Robertson Ken forkish Jeffrey Hilman these people live in a bakery they bake every day and they're feeding their starter multiple times per day their starter is in top shape because they're running a commercial operation they're running a bakery they're feeding it all the time this issue of a weak acidic starter is uncommon in a production baking environment but it's incredibly common for home Bakers because home Bakers don't feed their starter multiple times per day they they don't bake every day they put their starter in the refrigerator in the refrigerator for a week then they take it back out that infrequent baking schedule that a lot of Home Bakers follow is tailor made for creating acidity in your starter that's why you don't read about this in books written by professional Bakers but why it is rampant with home Bakers and before we go much further with my sweeping generalization about professional Bakers there is one exception to the rule my friend Thomas terrey shamblin from France he wrote this book published in English in 2021 souro baking atreus Thomas is a microbiologist and an incredible souro Baker in his book on page 80 he has a whole chapter called managing the acidity of your starter this is one of the few books that dedicates significant content to that topic because because if you're a Sourdough Baker the one thing that you have to be most concerned about is managing the acidity of your starter and your dough every bad thing that happens when you're baking sourdough other than maybe burning a loaf in the oven think of every other thing that can go wrong with your sourdough baking the vast majority of it is caused by acidity gummy crumb slow Rising weak starter premature over proofing all of those things that happen are caused by the acidity in your starter so as a Sourdough Baker this has to be one of the skills that you develop especially as a home Baker where that infrequent baking and infrequent feeding of your starter is prone to creating acidity and to really understand what's going on here all you have to do is go back in time to the creation of packaged yeast once packaged yeast was created they basically separated the yeast from the lactic acid bacteria that creates the acid in your starter so now all those problems I just talked about they go away if you don't use a sourdough starter because there's no lactic acid bacteria in this packet so this Made bread making very simple very consistent very easy and people started using packaged yeast because it eliminated all the problems caused by acidity but bread made with packaged yeast because it doesn't have lactic acid bacteria tastes like cardboard it just doesn't taste very good so that's the reason people got back into the sourdough baking is for the flavor that you get from the lactic acid bacteria which gives sourdough bread its unique sour flavor but with that comes all the problems of managing the acidity of sourdough bread that's why people quit using sourdough in bakeries that's why people quit baking sour at home is because it's hard the yeast that's in here here is trying to rise your Loaf and the lactic acid bacteria that's in here is trying to choke off the yeast and destroy your loaf so it's a hobby that has certain downsides and that's why people stop doing it and it's also why sourdough baking is a little tricky and it takes some technique to get it right so the way I like to think about this is managing the acidity of your starter and managing the acidity of your dough is a skill you have to develop as a Sourdough Baker and learning to deacidify your starter is just like doing routine maintenance on your car it's just like doing a periodic oil change over time for most home Bakers your starter will drift towards being more acidic and occasionally you have to intervene and fix that so before we go much further I just want to clarify that I am not a microbiologist even though I play one on TV and we are going to get into to some pretty serious science here so I am relying on the work of people like Thomas terrey chambelland and another great source is the book series called modernist bread by Nathan merold and Francisco magoya that also has some great research in it around souro starters souro acidity and the impact of acidity on your loaves but one of the unique things that I do have is a few years ago I built a sourdo strength Testing Lab here in the basement of The Institute and over the past couple of years I have run hundreds of scientific experiments comparing the impact on starter strength from feeding them different types of flour different feeding ratios different temperature of water and different hydration levels to name a few I know more about souro starter behaviors than I care to admit and what I'll be showing you here today is based on the scientific theory but also what I have observed with my own eyes I will also be simplifying some of the science science here in the interest of educational Clarity so now let's cover some Basics where does this acid come from that causes all these problems it's already in your starter jar there are two basic microbes in here yeast and lactic acid bacteria the yeast eats flour drinks water and it produces carbon dioxide carbon dioxide is what creates the gas that rises your dough and it creates your open Airy crumb in your leavened bread that comes from the yeast its symbiotic partner the lactic acid bacteria also eats flour drinks water and it consumes some of the byproducts of the yeast and it creates two types of acid lactic acid and acetic acid lactic acid is the yogurty type of Tangy acid that you would taste in yogurt acetic acid is that bright flavor of cider vinegar for purposes of simplification I'm generally going to refer to the acetic acid the vinegar type of acid just for Simplicity so these two microbes have traveled the Earth together since the beginning of time and they're locked in a symbiotic relationship in your jar the yeast is just trying to create carbon dioxide and the lactic acid bacteria is basically trying to kill the yeast this is just like ramulus and Remis or Canan aable in a jar Joseph Campbell could have written a chapter about sourdough starters in his famous book because when you put these two symbiotic organisms in the same place they get along together for a little while but then the longer they're in there the lactic acid bacteria will try to strangle the yeast and choke it off so for all the discussion going forward I'm going to talk about these six stages of the starter feeding cycle so first let's talk about what should your starter look like and smell like typically at each one of these stages stage one your starter is recently fed this is where you've just added flour and water to your carryover starter and it will essentially smell like flour and water there will not be a lot of other Aromas in there as your starter begins Rising it'll Rise Up from your starting line so most people will put a rubber band on their starter jar when they feed it when it starts Rising you'll begin to smell a ripe sweet smell some people say it smells like bananas cantaloupe green apple you'll smell a little bit of that sugary sweet ripeness the third stage is when your starter Peaks so this is an important stage to be able to identify visually after you feed your starter it will rise rise rise it'll be domed on the top it will get to a point where it stops Rising the Dome will flatten and when that Dome flattens on top that's the peak time of your starter that's an important time because typically you want to use it in your dough either right before or at that time that it's peeking now at that time that it Peaks it'll continue to have that ripe sweet smell and sometimes it will also begin to smell yeasty as it's reaching that Peak the fourth stage is when your starter begins falling so that flattened top now actually starts falling back down to the starting line and the aroma of your starter will change here because you'll start to smell a hint of acidity and you'll typically smell a beer and wine type of alcohol smell as you're starter passes Peak and begins falling stage five this is when your starter has fallen all the way back down to the starting line but there's still bubble activity on top so it's flat but active and typically what it will smell like here in that Fallen stage is this is when you'll first start to smell the pronounced vinegar smell from the acidity and Stage six when your starter is starving this means that the population of starter has consumed all the available food you'll see the bubble activity completely stop your starter is very acidic at this time and it'll smell like acid but it will also start to smell like alcohol which is a byproduct of the yeast when it starts running out of food and this alcohol smells different than that beer and wine smell this is more of a boozy alcohol smell more like vodka and then I'll just briefly mention that sometimes your starter can smell like acetone paint thinner or nail polish remover that's a very difficult odor to diagnose it can happen at any time in the feeding cycle I'm not going to cover that here I have a separate document on my website and it's in the description of this video you can download that and understand what to do with your starter if it smells like acetone here's a summary chart from that document you can pause here if you'd like to review this in more detail so we talked about what you can see and smell with your sourdough starter as it goes through that feeding cycle but now let's go inside the jar and understand that interplay between the lactic acid bacteria and the yeast so I'll use those same six stages of the starter feeding cycle number one when your starter is recently fed it's important to note when you feed your starter we take a small portion of carryover starter from the previous day and we add fresh flour and fresh water by doing that feeding it dilutes the acidity so that's the point in time where the acidity is the lowest possible point right when you fed your starter and the thing that loves low acidity is the yeast so when we're in that recently fed stage the lactic acid bacteria automatically starts generating acid it's the only thing that knows how to do but the yeast is in its happy place because the acidity is low so the the yeast starts reproducing and making new yeast cells and it starts generating carbon dioxide in that low acidity environment in stage two where your starter is now Rising above that recently fed line the lactic acid bacteria is still happy still pumping out acidity but it's still fairly low acidity and the yeast is still very happy and it's still reproducing more baby yeast cells and generating carbon dioxide at stage three your starter has risen in peaked the lactic acid bacteria is still happy it's always happy it just keeps producing acid and now the acidity level is moderately High because it keeps building up cumulatively but the yeast is at its highest carbon dioxide production now because it's at its largest yeast population and the acidity level is still not high enough to be choking off the yeast carbon dioxide production but then stage four we cross a threshold the starter begins falling after it Peaks it starts falling what happens here the lactic acid bacteria is still happy it's still pumping out acid but now the acidity level is high the acidity level is too high for the yeast to be producing an optimal capacity so the CO2 production the carbon dioxide that rises the dough starts dropping off very quickly because the yeast is choking on vinegar stage five the starter has now fallen back almost to the starting line there's still some small bubble activity on top but the lactic acid bacteria has now produced a very high concentration of acidity in the starter the yeast is totally choked off and there's really no meaningful carbon dioxide production happening at this point And now when the starter is starving there are no bubbles it's flat it's covered with Hooch on top it smells like alcohol and acid this is where you've reached the extreme acidity level for the lactic acid bacteria production and virtually no carbon dioxide production coming from the East so you can see here on that Top Line the lactic acid bacteria is always happy it's always producing acid it never stops the yeast on the other hand is happiest in that low acidity environment before the starter Peaks that is when the yeast is at its optimal reproductive rate and its CO2 production rate now there are two common misconceptions about what happens when your starter Peaks and it begins falling if you asked 100 people why does your starter begin falling after Peak 99 or maybe a 100 of them will say it's because your starter is running out of food it's completely wrong your starter has plenty of food what's happening is the acidity level Rose to a certain point where it chokes off the yeast the yeast stops producing carbon dioxide so it can't hold that height of the starter up anymore the carbon dioxide starts leaking out through the top of the starter and the starter begins falling the second thing that happens at the same time is as the acidity level increases in your starter it stimulates something called the proteas enzyme proteas enzyme lives in your starter and that's like little pack men that eat the gluten strands and they love acidity they get stim ulated when the starter becomes acidic so they start munching through the gluten and that's what causes your starter to fall after Peak as well and why it will become totally flat and pourable almost like the thickness of paint is because all that gluten has been chewed up by that enzyme the second misconception people have is when your starter Peaks they also think that the yeast starts to die off the yeast doesn't die off even though it stops producing carbon dioxide it just goes DOR hormon so the number of yeast cells really Plateau when it reaches that Peak and starts falling the yeast population is still the same they just can't produce carbon dioxide they go to sleep and they remain in a dormant State until the next feeding when you dilute that acidity down with fresh water and fresh flour and that wakes up those dormant yeast cells and they start reproducing again so I'm going to to do a little demonstration now to show you what happens during that starter feeding cycle and that interplay between the yeast and lactic acid bacteria but before that you're probably saying what the heck is Tom doing wearing an apron because I never wore an apron before in one of these videos but I'm also wearing a fancy shirt and this demonstration might get a little messy so I dug this apron out this is from when I used to work at the laboratory in NASA actually I never worked at the laborat at Nasa I bought this in the gift shop but I kind of wanted to work there and I think back now that maybe if I had made some different Life Choices things would have worked out differently for me but that's neither here nor there let's proceed with the demonstration okay what I'm going to show you here is an example of a very unique Barnyard that's inhabited by yeast and lactic acid bacteria the yeast will be played in this production by these little cows these cows eat flour and water which is grass and water in the barnyard and they belch out carbon dioxide pactic acid bacteria are played by this little Velociraptor and his friends this is an acid spitting dinosaur they also eat the grass and drink the water and they actually eat some of the excrement of the cow that's a little gross so they're not only an acid spitting dinosaur they're a cow eating acid spitting dinosaur these are the LA lactic acid bacteria in this demonstration so what we have here for the demonstration we have this tray this is the starter jar we have the green felt which is the grass that's also known as the flower we have the little trough here which is the water that you're going to feed your starter at the beginning of the process we have the cow that's the yeast and we have the dinosaurs that are lactic acid bacteria and the acid spinning dinosaurs are going to spit 100% cider vinegar so let's see what happens when we feed our starter so stage one we take a portion of yesterday's starter we feed it flour and water there is a population of yeast and lactic acid bacteria in that carryover starter that you use the lactic acid bacteria will always outnumber the yeast usually by 100 to one times but in this example just to keep the math simple we're going to start this off with two yeast cells which which are two cows and four lactic acid bacteria cells represented by these little miniature acid spitting dinosaurs now as soon as we feed this the yeast start pumping out carbon dioxide the lactic acid bacteria start pumping out acid and just to keep the math straight we're going to assume that each one of these little acid spitting dinosaurs spits out five milliliters of acid at each one of those six Cycles in the starter feeding cycle so we have four dinosaurs times 5 milliliters I have 20 milliliters of acid here now what happens is they're going to spit this out into the grass and into the water and onto the cows and when the cows eat the acid they become incapacitated and they can't create carbon dioxide anymore so in this first stage we don't have that much acid here so I'm just going to spread this out around each one of these four dinosaurs oh I hit one of the cows with it so we have 20 mlit of acid but you can see the cows still have clean water they still have a lot of grass let's move on to stage two Rising stage two our starter is rising this is that zone that's the yeast's happy place so these cows are happy they're not only pumping out carbon dioxide they're pumping out baby cows also known as calfs so they actually create six baby cows in that process so now we have eight total cows in here pumping out carbon dioxide and the lactic acid bacteria like I showed on that chart they're happy all the time so at every one of these six stages they just double their population at every cycle so our four acid spitting dinosaurs become eight but now as we go through the cycle eight acid spitting dinosaurs each spit 5 ml of vinegar into the Barnyard so that's 40 ml here's 40 mL of vinegar so I'm going to add a little bit to each one of our acid spitting dinosaurs here and you can see now it's getting in front of the cows there's a little bit going in the water so there's still some patches of grass here that haven't been contaminated with the acid yet but you can see the cows are losing a little bit of their eating space stage three now the starter is peaking the cows are pumping out carbon dioxide but they're starting to eat some of the acid because it's in the grass and it's in the water so now they only produce four baby calvs so I had eight cows and now my reproduction rate is slowing because that acidity is growing so I have four baby calves still pumping out carbon dioxide my eight acid spitting dinosaurs always double at each cycle they create eight more so now we're up to 16 16 acid spitting dinosaurs create 5 milliliters of acid each so that's 80 milliliters of acid now getting piled on here now look what happens now almost all the grass is contaminated there's acid in the water so all these cows are really struggling to find a patch of grass that's not contaminated with the acid stage four we're past Peak and we're falling and if you remember from the previous charts this is where that cut off point is where the yeast is now past its optimal CO2 production a lot of these cows are eating acid now when they eat acid that's a contraceptive so they stopped producing there are no new baby cows after the peak and six of these cows ate so much acid that now they're incapacitated so I'm going to tip six of these cows over so six cows are down because we passed the Tipping Point that's little joke for the wisconsinites and we have 16 acid spitting dinosaurs in here they double each cycle so 16 new ones get added so you can see once that starter is past Peak the lactic acid bacteria really start overrunning the yeast now we have 32 acid spitting dinosaurs spitting 5 milliliters of acid each that's 160 milliliters of acid added to our starter jar you can see there's almost no dry grass here left there's nothing left for the cows to eat everything's been saturated with acid at this point stage five it's a bad scene these cows are swimming in acid three more cows are down totally incapacitated not creating any carbon dioxide there's only three viable cows left in here they can't produce anymore because they're swimming in acid but our lactic acid bacteria always double no matter what 32 turn into 64 here they come 64 acid spitting dinosaurs create 320 milliliters of acid this is what your starter looks like when it's in that Fallen stage when it's back down to the starting line it's swimming in acid but we're not done yet one more step step six this is when your starter is starving it's covered with Hooch it's swimming in acid all the cows are down totally incapacitated no carbon dioxide production happening here at all 64 acid spitting C seeds of Satan turn into 128 here they come pterodactyls coming in hot 128 acid spitting dinosaurs create 640 milliliters of acid this is a barnyard tragedy here's what we just observed in the demonstration Illustrated in four simple charts first the cow population representing the yeast grew very rapidly until the starter peaked and the acidity reached a Tipping Point that caused the population to plateau and then as the cows ingested the acid they became incapacitated and stopped producing carbon dioxide the dinosaur population representing the lactic acid bacteria grew unabated doubling at each of the six stages this caused the cumulative acid production to grow exponentially which then caused the carbon dioxide production to Peak as the starter was peaking and then rapidly fall in the last three stages as the acidity grew resulting in no carbon dioxide being produced in stage six so after all the charts and the demon rtion have we answered the question what causes an acidic starter we have and it's simple you basically don't want to wait too late in the starter feeding cycle to discard and refeed because you carry over a massive amount of acidity into the next day's starter so the worst time to discard and feed is when your starter is starving so for example if you were doing a 111 feeding ratio where you discard 2/3 of your previous starter and you carry over 1/3 thir that's just like taking a 1/3 slice of the Barnyard so at that stage six starving you would be carrying over four unhealthy cows 42 dinosaurs and 420 mL of acid contrast that with the best time to feed your starter which is when it is at Peak one3 slice of the Barnyard at Peak has four healthy cows only five dinosaurs and a massively smaller amount of carryover acid then you might ask the question if it's better to feed earlier why don't we feed before Peak and that's because until the starter Peaks it hasn't regrown the yeast population from the previous discard so you never want to discard and refeed before it Peaks because then you're shrinking your yeast population and then you may also ask what if I can't catch my starter at Peak there is obviously an acceptable range between your starter's Peak PE and when it's starving but just be aware that your starter becomes more acidic the further down that curve that you wait to discard and feed your starter in part one we learned how to identify the symptoms of a weak acidic starter and we understand now what happens in that typical feeding cycle of your starter with the interplay between the yeast and the lactic acid bacteria that can cause your starter to become acidic now we'll apply that knowledge to figure out how do we remediate a weak acidic starter and there are basically two methods number one the high feeding ratio method and number two the peak-to Peak feeding method so the easiest way to fix an acidic starter is just to give your starter a high feeding ratio and sometimes you can fix it in one feeding so let's talk about feeding ratios and I'll explain how this works so your starter feeding ratio the most common one that people use for daily maintenance is a 111 feeding that's three numbers and it's the ratio of carryover starter flour and water so let's say you keep 150 gram of starter that means you would carry over 50 gram of of starter you would feed it 50 gram of flour and 50 gram of water that's an equal Parts ratio 111 when you use that 111 ratio that's the lowest possible feeding ratio you'd ever want to use because you're carrying over a fair amount of the acidity from the previous day starter so if you think back to our example where our fallen starving starter was loaded with acidity if we're carrying over onethird of what's in our jar and then we add equal parts flour and water we're not significantly diluting that Mass massive amount of acidity that came over in a 111 feeding so that's actually what can build up that residual acidity over time is using a low feeding ratio like 111 so then people say well what if I went up to 122 A 122 feeding ratio would be two times flour and two times water compared to the carryover amount so in this example that would be 30 gam of starter that we would carry over and we would feed at 60 G of flour and 60 G of water a 122 feeding ratio is not materially different than 111 so what I recommend to really knock down the acidity is you have to use something like a 155 feeding ratio or a 11010 feeding ratio so just to do the math here for 150 gram of starter and I'll round the numbers here slightly if you wanted to do a 155 feeding ratio to knock down the acidity you would carry over 15 G of your existing starter and we're going to to feed that five times as much flour that'd be 75 G of flour and five times as much water 75 G of water that will significantly knock down that carryover acidity that's coming from the previous day's starter if we went up to 11010 and rounding these numbers slightly that would mean we would only keep seven gram of starter out of this jar that's a tiny drop of starter in the bottom and we would feed that 75 gam of flour and 75 G of water that massively knocks the acidity down by using a tiny tiny amount of your carryover starter from the previous day sometimes you can remediate this problem with one big feeding like that because you're flushing out all of that acidity that carried over from the previous day Starter by just using a very small amount of it to feed your new starter so the way this works and it's pretty obvious is through dilution we're diluting that massive amount of acidity in the starter jar with the next feeding so if you assume this jar of water colored with blue food coloring represents a very acidic starter if we did a one one feeding and I'll just approximate these for an example and I feed this equal parts flour and water you can see with a 11 one feeding I've slightly diluted that down but it's not really significantly different now compare that to if I did a 11010 feeding where I take a tiny amount of the previous day's starter and I feed that 10 times flour and 10 times water now you can see that dilution effect very clearly right there by using a 11010 feeding and that's only if you do it one time now imagine if I take this 11010 and I do another 11010 with this I feed it 10 times water 10 times flour now look at the dilution effect from that original starter just with two of those 11010 feedings in a row so you can see the massive impact that you have in diluting the acidity by doing the high feeding ratios that's a great method but there are two important caveats with this High feeding ratio one is you can't feed the starter too late and the second is you can't feed the starter too early so let's talk about what that means if I do a 11010 feeding ratio and then I just let this sit until it rises Falls and is completely starving it will turn itself back into the starter that it originated from because the yeast population and the lactic acid bacteria population that ratio of those cells is what was carried over into this starter we diluted it which gives the yeast a Runway to reactivate the yeast so the yeast does get a little bit of a Head Start but you still have a lot of lactic acid bacteria cells in this jar and if you give them enough time and let that starter completely fall flat again it will get very close back to where it started so when you do a high feeding ratio you don't want to feed it too late meaning you don't want to get it let it get back to that completely fallen or starving level you want to catch it sometime before that and then the second rule is you don't want to feed it too early this is critically important and a lot of people make this mistake is they say Tom said do a 11010 feeding ratio so you do 11010 ratio but your starter will take a really long time to Peak with 11010 because we use just a tiny drop of starter in here so then people get impatient and they wait and wait and their starter's not rising and then they say but Tom said if I do two 110 T back to back that'll really strengthen it and then they discard it before it Peaks you do another 11010 feeding and you know where I'm going with this you're massively weakening your starter because you never let the yeast population grow back to where it was before you discarded so if we do a 110 10 feeding that tiny drop of yeast or of starter that we put in this jar it has to multiply its population by 20 times just to get back to where it was before you discarded and fed so if you discard and feed again before it Peaks you're massively weakening that population so always always allow your starter to Peak before you feed it never discard and feed your starter before it Peaks because that actually weakens it so I've described this technique in some of my other videos and for some reason people still get confused by this so let me just be clear a high feeding ratio does not weaken your starter unless you discard before it Peaks I can't be more clear about that and people will watch this video and somebody will say I'm doing a high feeding ratio and people will say oh no no Tom from the souro journey says if you do a high feeding ratio that weakens your starter it doesn't it only weakens your starter if you discard before it Peaks once it gets to Peak and pass it strengthens your starter so that's why these two rules apply never discard a high feeding ratio before it Peaks and always discard and refeed before it falls completely flat so you have that pretty big window to refeed after it Peaks and before it falls flat so the second method for deacidifying a weak starter is to use the peak-to peak method now this is basically doing short interval feedings over a short period of time where you discard and refeed your starter as soon as it Peaks hence the name so now let me explain the details of the peak-to peak method let's assume that I have 150 gram of a very acidic weak starter here now the way I'm going to do this is instead of using the high feeding ratio method that I talked about earlier I'm going to do a fairly low feeding ratio of one two2 so that's two times flour two times water compared to the carryover amount but I'm going to do these over a very short feeding interval and I'm going to watch my starter very closely and as soon as my starter Peaks I discard and feed again so this is more of a time-based method because I'm trying to compress this process into two days so I can do it over a weekend for example so here's what I would do let's say at 8:00 in the morning I take my very acidic starter 100 50 g total I'm going to discard 80% so I'm going to keep 30 gram of my starter I'm going to feed that 60 G of water and 60 G of flour that's my 122 ratio and then I set this starter in a place where I can see it and I watch it and watch it and watch it and I wait for it to Peak so as soon as that Dome stops Rising it domes on top and then the Dome flattens out that's the Peak at that time I immediately discard and refeed the same feeding ratio again so let's say did that at 8:00 in the morning and let's say it takes 8 hours to Peak because that's a characteristic of a weak starter is that it's not peaking in 4 hours after feeding it's taking a long time so at 4:00 in the afternoon my starter Peaks 8 hours after feeding I immediately discard and feed again one 122 and I watch it again and now 10:00 6 hours later it Peaks very something very important is happening here the first Peak to Peak method it peaked in 8 hours on the second feeding it peaked in 6 hours that's what I want to see you want to see a shortening time to Peak so this is working but now I have a problem because it's 10:00 at night and if I do one 2 two feeding at 10:00 I have to get up around 2:00 in the morning to check my starter to see if it's peeking and feed it again I don't want to do that so what do you do with the peak to Peak method when you run into that problem the easy thing is put it in the refrigerator come back the next morning and pick it up again that's the simplest way to do it another option is that you can do a very high feeding ratio at 10:00 at night let's say I do 110 10 feeding and that'll just stretch out the time so that it's not going to Peak until morning but that's a little risky because I don't know when a 11010 ratio will Peak with this starter so the third option is I put my starter on ice so at 10:00 at night night I know if I feed this one 122 it'll peak in the middle of the night so I feed it one 122 but I put it in a bowl of ice at 10:00 it will take about 4 hours for this ice to melt and the starter won't do anything until the starter melts and the the the starter temperature comes back up to room temperature so it's just like feeding it 4 hours later it's just like feeding this at 2:00 in the morning and if I use more ice it's like like feeding it at 3:00 or 4:00 or 5:00 the general rule that I use is I use two times the amount of ice in weight compared to the starter to delay it about 4 hours and there's no exact science here because it depends on your room temperature but just to give you a ballpark if I have 150 gram of starter I'm going to put 300 gram of ice in this bowl and that'll delay the start time by about 4 hours it's just like I got up at 2:00 in the morning to feed this so that gets me through the night I do my third feeding by catching it at Peak the next morning and if that peaked let's say in 5 hours and I fed it at 7:00 so now my cycle is it peaked in eight hours after the first feeding 6 hours after the second feeding 5 hours after the third feeding I do the peak-to Peak feeding again on the fourth feeding it peaks in four hours that's not uncommon to really get this back in top shape in three to four feedings or I could do one or two more peak-to Peak feedings but once you get to that 4-Hour rise that's pretty much where you want it to be now I love this method and I recommend that everybody learn this peak-to peak method because you can use it all the time if you keep your starter in the refrigerator let's say for a week or two weeks or 3 weeks because you don't bake and then you take it out of the refrigerator your starter will be acidic and it will be sluggish do one two three of those peak-to Peak feedings it'll immediately bounce back if you leave your starter out during the summer and it gets very hot in your kitchen becomes very acidic very weak do one or two of those peak-to Peak feedings it'll bounce back really quickly so this is a real common technique that I use just to jump start my starter occasionally and then periodically like doing the oil change maintenance on your car if your starter is just drifting slowly and slowly towards that weeken state let's say once a month once every two months once every 3 months you take it for a spa day and you do the peak to Peak feeding give it a little TLC and it'll bounce back to full strength I use it all the time so now let's talk about the science behind the peak-to Peak feeding method and the reason I want to show this in detail is because when I do this I use a pH meter and I test the pH of my starter when I feed it and when it Peaks and I can tell by that pattern between the changing pH levels that the starter is definitely deacidifying but I don't want you to have to go out and spend the money on one of these devices so I'm going to show you the detail of this experiment so you can observe what I'm doing and then you'll be able to tell just from the way your starter behaves you can approximate what's happening with the acidity without needing to buy a meter now to understand the science behind this we need to talk a little bit about the pH scale the pH scale is a way to measure the acidity and the thing that's a little confusing about it is it's an inverse scale so if your starter has a high degree of acidity it will have a low ph and if it has low acidity which is favorable it will have a high pH so we basically want a starter with a high pH not a low PH a good way to illustrate this is by looking at the acidity of vinegar versus water pure cyer vinegar has a pH of 3.0 that's very acidic water has no acidity this has a pH of 7.0 so these are our two bookends a very acidic starter will have a pH of about 3.7 it'll be down here in the neighborhood of vinegar you don't want your your starter sitting down here when you initially feed your starter and you dilute down the acidity it will have a pH of about 5 point five which moves it up into this range so now I'm going to go through this example and show how with each one of these short interval feedings using the peak-to peak method you're going to see how this pH of the starter moves farther away from vinegar which is what we want and closer to water so in this example we start with a starter that has a pH of 3.7 it's very close to vinegar now you would know this without having a pH meter because it has all the tell tail SS we talked about in the first part of the video it smells like vinegar it's flat it takes a long time to Peak it takes a long time to rise the dough and it creates a dense gummy crumb it's unmistakable that this is a weak acidic starter sitting down here close to vinegar so now we start the peak-to peak method so we discard 80% we do a one 122 feeding and our diluted fed starter now has a pH of 5.0 then the lactic acid bacteria starts producing acid the starter now Peaks at 3.8 so it's getting better it went from a 3.7 to 3.8 but it took 13 hours to Peak so that's a Telltale sign of a weak acidic starter we're looking for it to Peak in about 4 hours is taking 13 hours so as soon as it Peaks discard 80% feed one two2 again now my diluted starter goes up to 5.1 the lactic acid bacteria starts producing acid said the yeast starts Rising the starter towards Peak now it Peaks at 3.9 so again we're moving in the right direction and most importantly it peaks in 6 hours so you can tell you're deacidifying and strengthening your starter because we just cut our time to Peak from 13 hours to 6 hours and the way that happens which we know from the first part of the video is because by diluting that acidity down it favors the yeast the yeast produces more yeast cells the East produces more carbon dioxide you can see evidence of that just with these two cycles where it went from a 13-hour Peak to 6 hours to Peak now we discard and feed again the third time now my diluted starter recently fed is at 5.2 again moving slightly to the right it starts peaking as the lactic acid bacteria is producing acid now we Peak at 4.0 and we do it in four hours so we went from a 13 hours to Peak 6 hours to Peak 4 hours to Peak and now we're at a pH of 4.0 which is much better than 3.7 but the number I typically look for for the ideal pH at Peak is about 4.1 so I'm going to do one more cycle here we discard 80% our diluted starter after it's fed is now at 5.4 so again it's climbing each time we feed it which proves that our acidity is going down and it peaks in 4 hours again and now I'm at my target of a 4.1 pH which is where I want to be so our time to Peak went from 13 hours to 6 hours to 4 hours to 4 hours you could do this one more time and when it generally plateaus at that 4 hours to Peak three times in a row you know that your starter is at a good acidity level like 4.1 and you don't have to guess you can look at the criteria that we talked about at the beginning of the video it doesn't smell acidic it smells yeasty it's frothy it has huge bubbles in it it's stringy it smells sweet it will look and smell completely different than it did when we first started the first feeding so that's an illustrative example of how it works I'm going to put this chart up on the screen you can see all the numbers here if you want to review this in detail one of the things we haven't talked about yet is the impact temperature has on your starter and its acidity so there are a couple Simple Rules around this the lactic acid bacteria loves warm temperature the warmer the better if you heat up your starter the lactic acid bacteria just pumps out acid like crazy and it has another partner in the jar which I talked about briefly the proteas enzyme proteas enzyme is like the pet of the lactic acid bacteria and when it starts pumping out acid and the temperature gets warm it releases its little Tasmanian Devil pet that starts buzzing around through the starter and cutting through all the gluten strands and eating all the gluten it's really a mess once that proteas enzyme gets released that's what causes over proofing in your dough the thing that releases it a lot of acid and warm temperatures so if you're ever trying to warm up your starter to speed it up never let your starter sit above 80° F or 27° C for a long time because it will become massively acidic on the other end of the spectrum you have the refrigerator when you put your starter in the refrigerator that's a great way to just put your starter to sleep but it doesn't go entirely to sleep when you put your starter in the refrigerator I tend to think of it as if one week in the refrigerator is the equivalent of one day at room temperature so if you leave your starter in the refrigerator for a week it will go through that rising and falling cycle and it will become acidic but the problem is you don't see that happen in the refrigerator because the refrigerator temperature is cool it compresses the carbon dioxide gases in in the starter so you don't actually see it rising and falling even though it's essentially rising and falling but the temperature is shrinking the the gases like when you put a a balloon outside in the winter or if you put a balloon in the refrigerator or Shrink the gases so you don't see it rise and fall and some people think oh my starter is perfectly fine I put it in there on Sunday and I took it out the next Saturday it looks exactly the same it will become acidic in the refrigerator so always be aware of that that the refrigerator slows things down but it doesn't stop stop it so now we talked about the ways to remediate a weak acidic starter which is through a high feeding ratio or the peak-to peak method but then people say do I have to do that all the time like do I have to do the peak-to peak method do I have to feed my starter four times a day to keep it in top shape this is the most complicated and confusing part of maintaining a sourd starter if you don't bake every day and I talked about this earlier commercial bakeries don't worry about weak or acidic starters because they have somebody feeding their starters constantly if you're baking once a week or once every two weeks or or or intermittently maintaining your starter can be complicated so there are a few things that I'll recommend one is if you're baking once a week or less I recommend keeping your starter in the refrigerator so there are many many any different refrigerator maintenance methods I'll do a separate video on that there's almost an uncountable number of them but the basic idea is if you're if you're baking once a week but say on Saturday I keep my starter in the refrigerator and then I'll take it out of the refrigerator on Friday and I'll do a couple of those peak-to Peak feedings on Friday and it'll come back to full strength by Friday night then on Friday night I'll build 11 and 11 is just a high feeding ratio that I'm going to use in my batch of dough the next morning so let's say I need 200 gam of starter for my dough I'll take 20 gram from my my main starter I'll put that in a jar with 100 grams of flour 100 gram of water I'll make 220 gram of of starter to be used the next day for my dough and then I put the remaining starter in my refrigerator for a week and I just leave it there so so this is where I leave it in the refrigerator and then I take it out about one day before I need it and I give it a few of those refresh feedings that works perfectly fine if you bake less frequently let's say you bake once a month you feed your starter you put it in the refrigerator and you come back in a month it will be more acidic and it will take a few more feedings to get it back in shape so I might take it out of the refrigerat refrigerator two days before I need it or you know worst case three days before I need it and you just give it a couple of feedings and it'll bounce back your starter will come out of the refrigerator fairly strong you'll be surprised the refrigerator is your friend when you're trying to control your starter and to minimize the amount of Maintenance that you're doing so in closing if you're a souro baker you need to develop the skills to manage acidity the acidity in your dough starts with the acidity in your starter the acidity in your starter is something you can manage and you need to learn how to do that that's your job as a Sourdough Baker in my opinion is really managing acidity the starter makes the bread the bulk fermentation makes the bread sometimes we just need to stay out of the way but if you let your starter become too acidic that's when all the bad stuff happens in your bread and things start to go south in a hurry so thanks for sticking with me on this long video and good luck on your sourdough Journey [Music]

Channel: The Sourdough Journey

Views: 23,667

Keywords: cows and dinosaurs, peak-to-peak, weak starter, how to make sourdough, cleveland, sourdough starter, acidic starter, deacidify starter, my starter is weak, strong starter, how to strengthen sourdough starter, nasa apron

Id: PBhCXlSq6G8

Length: 60min 46sec (3646 seconds)

Published: Fri Feb 23 2024