When is Bulk Fermentation Done? - Episode 8: “Low and Slow at 70F/21C"

hi i'm tom coming to you from the international institute for the advancement of sourdough science and research of cleveland ohio also known as my kitchen thank you for selecting this video today's video is the eighth episode in the series when is bulk fermentation done in this series we try to tackle the most complicated part of sourdough baking especially for beginners and that is trying to understand all the variables that impact bulk fermentation to help determine when bulk fermentation is finished now in today's episode we will tackle one of the most confounding aspects of bulk fermentation and that is answering the question how can two recipes call for vastly different percent rises in the dough in bulk fermentation and come out with similar results at the end now for example in all the experiments we do here at the institute i use chad robertson's basic country loaf recipe this calls for a 20 to 30 percent rise in the dough during bulk fermentation there are other recipes that call for a doubling of the dough or a 100 rise in the dough and they make equally good-looking and great-tasting loaves of bread how is this possible this is one of the most confusing aspects of reading sourdough recipes and really understanding when to cut off bulk fermentation because you'll see these wildly different recommendations for the percent rise in the dough to signal the end of bulk fermentation so in today's experiment we're basically going to tackle this question so with all of our experiments here at the institute we always start with doing some background research so i looked at a number of recipes probably 20 different sourdough recipes and looked at the recommended percent rise in those recipes and it's all over the map so what i did is i found three recipes that we will look at today and compare these to chad robertson's basic country loaf recipe and tartine bread as i said 30 percent rise recommended in tartine then i have three recipes here two that call for a doubling of the dough and one that calls for at least a doubling and preferably a tripling of the volume of the dough in bulk fermentation they all make loaves that look almost identical how is this possible so as i looked at all these different recipes i started to find one significant difference that may explain the difference in the percent rise and that is temperature the bulk fermentation temperature that's recommended is highly correlated with the percent rise that's recommended to end bulk fermentation for example tartine bread recommends a 20 to 30 percent rise in the dough the recommended bulk fermentation dough temperature is 78 to 82 degrees fahrenheit that's fairly warm that's 26 5.5 to 28 degrees celsius when you compare these other recipes the recommended rise is typically doubling or more and the recommended temperature in every one of these recipes is lower than 21 degrees celsius or 70 degrees fahrenheit so that's a significant difference so my hypothesis is that the percent rise in the dough and bulk fermentation is highly correlated with the bulk fermentation temperature so in today's experiment we're going to try to prove that so just for comparison to tartine which calls for that bulk fermentation of 78 to 82 degrees fahrenheit or 25.5 to 28 degrees celsius there are three other recipes that i looked at that all fall in a similar range one is emily rafa from the clever carrot her beginning sourdough recipe recommends a doubling in the dough and it recommends a bulk fermentation temperature of 68 to 70 degrees fahrenheit or 20 to 21 degrees celsius i also looked at elaine body's master recipe from the food bod website her recipe calls for a doubling of the dough and even cooler 64 to 68 degrees fahrenheit or 18 to 20 degrees celsius that's a very cool overnight bulk fermentation recommendation the third recipe is from ken forkish and this is from his overnight country blonde recipe from the book flour water salt yeast he calls for a tripling in the volume of the dough in an overnight bulk fermentation he does not give a specific overnight bulk fermentation temperature but he mentions throughout the recipe that his room temperature during the day presumably is 70 degrees fahrenheit so we can presume that the overnight temperature is 70 degrees fahrenheit or less that would be 21 degrees celsius and he calls for a 12 to 15 hour bulk fermentation so when you compare all of these recipes that are calling for a doubling or more of the dough volume during bulk fermentation all these temperatures are below 70 degrees fahrenheit now for today's experiment i'm going to follow the tartine recipe but i'm going to bake four loaves of bread and bulk ferment all of them at 70 degrees fahrenheit or 21 degrees celsius what i'm going to do differently is i'll let one of those lobes rise 30 percent which is what the tartine recipe would recommend we'll do one at a 50 percent rise 175 rise and one or doubling or 100 percent rise and then we'll bake all those up tomorrow and when we cut them open we'll compare the crumb of those four different percent rise to the i have hundreds of examples of what the tartine crumb typically looks like and then we'll be able to determine what that benchmark is to say if you're going from 80 degrees fahrenheit at a 30 percent rise what is the equivalent percent rise at 70 degrees fahrenheit or 21 degrees celsius to get the exact same looking crumb that's the experiment now for today's experiment like all the experiments that i do i'll be following the tartine basic country loaf recipe if you're not familiar with this recipe you can download it from the tartine bakery website the only thing that we're going to change is the bulk fermentation temperature and the recommended percent rise now one of the added benefits of doing this experiment is that we will also be able to test the incredible bulkmatic system if you're not familiar with this tool we developed this here at the institute and this was launched in episode three of this series so you might want to go back and watch that first to understand how we use this tool but it's basically a nine criteria test to determine when bulk fermentation is done however this tool is specifically calibrated for the tartine recipe so it's calibrated for the 80 degree fahrenheit 27 degrees celsius bulk fermentation temperature and the times are also calibrated based on that temperature so what we'll be doing here today is ignoring the recommended temperature and time because we're using a different temperature 70 degrees fahrenheit 21 degrees celsius the time is going to be whatever it takes to get that percent rise and we're also ignoring the recommended percent rise of 30 for three of the four lobes so we're basically significantly changing up some of the variables here but i still want to use this tool so that at each one of those loaves being cut off at 30 percent rise 50 percent rise 75 percent rise and a doubling will compare the other six criteria to say what does the dough look like what does it feel like what does it smell like again to try to calibrate what a 70 degree fahrenheit 21 degrees celsius bulk fermented loaf should look like feel like and smell like then we can have a different version of the tool for a 70 degree loaf so now let me recap the details of the recipe if you're not familiar with it the reason i include all of this in my videos is because i want these videos to be scientifically repeatable experiments so that if you follow these exact steps at home using the same ingredients using the recipe i provide all the details here so that you can produce exactly the same outcome that i'm producing there are very few videos like this that's part of the reason these videos are long is because i don't leave out anything that's germane to the outcome of the experiment it's all here so in today's experiment i'm using the same flour that i've used in all seven of the prior videos it's 90 bread flour 10 whole wheat flour that's called for in the recipe the 90 red flour i split in half so 45 of my total flour is the central milling company high mountain high gluten flour 45 of the total is central milling company artisan baker's craft plus and 10 is king arthur whole wheat organic flour those are the same flours i use all the time we start with that thousand grams of flour then we add 750 grams of water 200 grams of leaven and 20 grams of salt so in the baker's percentages it's 75 percent water 20 11 2 salt i follow all the steps in the recipe exactly by the book if i deviate from any of those i'll let you know and here's the summary of the recipe i'll put that up on the screen so you can pause here if you want to look at that in more detail so the question for today's experiment is how can you have a different percentage rise in the dough and bulk fermentation and come out with the same results and the hypothesis is that because the temperature is different in bulk fermentation lower temperature bulk fermentations can handle a higher percent rise in the dough that's really what we're going to try to prove here today now when i've done experiments in the past i can say anecdotally i have definitely seen this when you bulk ferment dough at lower temperatures the dough remains stiffer and it just has a firmer architecture than warm dough it's like any other food that you're cooking in your kitchen when you heat things up they tend to relax they tend to flatten out the same thing is happening with the dough and even though these temperature ranges are much lower than the ranges you would typically be cooking at the fermentation process is essentially cooking the dough so we're basically saying that the 70 degree fahrenheit loaf 21 degrees celsius that that dough is cooking at a lower temperature than the recommended 80 degree fahrenheit 27 degrees celsius loaf in tartine which is cooking at a higher temperature so if i'm cooking something at a higher temperature i would expect it to be softer more relaxed and flatter and that's essentially what i believe is happening here it's just that basic chemistry of the molecules are moving more rapidly at higher temperatures that's causing the gluten to relax and that that allows the cooler loaf to rise more than the warm loaf where the gluten matrix is more relaxed now in addition to the temperature differences impacting that architecture of the dough or the stiffness of the gluten matrix the ability to hold more air in a higher structure versus a flatter structure in the more relaxed warmer dough the other thing that happens when you bulk fermented higher temperatures is you're also changing the chemistry of the dough when you start to bulk ferment at 80 degrees fahrenheit or 27 degrees celsius for example you start to favor the lactic acid bacteria more than at lower temperatures and it raises the acidity of the dough when you raise the acidity of the dough that stimulates something called the protease enzyme the protease enzyme eats gluten and it starts to break down the gluten matrix so as your temperature increases the acidity increases and that protease enzyme reaction increases so essentially it's flattening the gluten matrix it's kind of like you're trying to build a house at a warm temperature but the termites are eating the house from the bottom up so when you're building the third floor they've eaten the first floor and you're already back down to a two-story building that is exaggerated at higher temperatures the protease enzyme is particularly exaggerated when you get up to 90 degrees fahrenheit or 32 degrees celsius which is really the highest meaningful bulk fermentation temperature you can really operate at that's where you see significant gluten deterioration because of the effect of the protease enzyme that's happening in the 80 degree loaf as well 27 degrees celsius just not as fast or as evident as it's happening in that warmer loaf so as the loaf is trying to rise the warm temperature of an 80 degree loaf relaxes the gluten so it just slumps the dough down a little bit and the protease enzyme starts to eat the gluten so no matter how hard the yeast works it is not able to inflate the matrix because the enzyme is popping the balloons that the yeast is trying to inflate now let me try to demonstrate this impact that temperature has on the gluten matrix through something that i call the linguine example so when you try to understand how the temperature could impact the percent rise for me it's helpful to have a visual to show what does the gluten look like at different temperatures so for that reason i created the linguine example and yes i just came up with this a few minutes ago so basically what i did is i took 20 strands of linguine i boiled one batch of them for about three minutes another one for nine minutes and another for 15 minutes what i'm trying to demonstrate here is what do the gluten strands look like and feel like at different dough temperatures so our 70 degree fahrenheit 21 degree loaf would look kind of like this that's the al dente that still has a lot of structure it's still very firm when you get up to 80 degrees fahrenheit or 27 degrees celsius this is pretty soft and your dough will start to relax more so this is just based on that temperature you see that relaxation of the dough and then at 90 degrees fahrenheit the dough is as relaxed as it is in the 80 degree loaf or the 27 degrees celsius an hour 32 degrees celsius but the other thing that happens at 90 degrees fahrenheit is you release the protease enzyme the protease enzyme is the uninvited party guest that comes along with the lactic acid bacteria this is the protease enzyme so what happens when you get up to 90 degrees fahrenheit or 32 degrees celsius and you're trying to do bulk fermentation the protease enzyme comes to the party and it breaks the gluten strands it eats the gluten it loves the taste of the gluten matrix and the protease enzyme really goes to town on your gluten so now you have the baseline here of a 70 degree loaf 80 degree loaf 90 degree low and now we try to understand why the cool temperature loaves would be taller when you think about that dough in bulk fermentation than the warm temperature loaves so now let me let me move these into a vessel and we'll see how tall they look so now i've transferred the linguine into these three beakers so that we can envision what does the gluten architecture look like what does the gluten matrix look like at different temperatures at low temperatures the gluten matrix is tall i mean it just keeps that architecture it's because it doesn't relax as much at low temperatures when you get up to 80 degrees fahrenheit 27 degrees celsius the gluten relaxes it just sits down in the bowl you can still make perfectly good bread with that and the yeast will still fill the gluten matrix but the gluten matrix is just softer at warmer temperatures and when you get up to 90 degrees fahrenheit or 32 degrees celsius you have a very flat gluten matrix and your gluten strands have also broken down because the protease enzyme this is what overproofing looks like is a flat loaf with deteriorated gluten so that's an example just to show the visual and this makes perfect sense if you went to a county fair and they were having a contest to see how high you could stack a ball of dough and you had an option to take the 70 degree ball of dough or the 80 degree ball of dough you're gonna take the 70 degree ball of dough because it's stiffer it just makes perfect sense i'm really going on and on about this but it's kind of frustrating because in all the time that i've spent studying sourdough baking sourdough and reading recipes nobody has ever really come out and said this that when you bulk ferment at low temperatures you'll get a higher percent rise than bulk fermenting at warmer temperatures and you could produce exactly the same loaf at the end the dough before it's baked just happens to be more relaxed at warmer temperatures now we really haven't proven anything this is really just a statement of our hypothesis but when you ask the question now and say how can a 70 degree loaf ball ferment and double in volume and how can an 80 degree loaf bulk ferment and rise 30 in volume that's a pretty good indication right there and the thing to remember is the number of gluten strands are exactly the same so these can still produce the exact same loaf in the end the gluten matrix has the same number of cells the warmer temperature gluten matrix is just more relaxed than the cooler temperature gluten matrix during bulk fermentation but these two lobes could bake up exactly the same way that's what we hope to prove in this example in the interest of time i've mixed all the ingredients off camera as i mentioned i follow the tartine recipe by the book you can see all the detailed steps in many of my other videos but i'll point out a few things just so we have the full documentation in this video for the record so i always like to make some note of what my levin or my starter looked like because in one of my recent videos we showed that whether you're using a strong starter or a weak starter can materially impact your bulk fermentation time and even though we're not really precisely doing an experiment on bulk fermentation time here i do like to have a record of that so i made 11 per the recipe last night it's essentially a 1 10 10 feeding of your starter using a 50 50 mix of bread flour and whole wheat flour in the morning the leaven had risen i'd say about 50 it was bubbly on the sides but it hadn't quite risen as much as i expected it to and there were no bubbles on the top and it still didn't really have that ripe smell so i let it go 12 hours from when i initially mixed it my kitchen temperature was relatively cool last night which is 69 degrees fahrenheit that's 20.6 degrees celsius so after 12 hours 11 looked really good it had about doubled in height in the vessel here's a video of what the lemon looked like the next morning i also did a float test there's a lot of controversy about whether the float test works or not but if you follow this recipe the float test is reliable and it's recommended in the book so i did the float test you can see here a really nice float of of my leaven and then lastly here's just a quick video of the lemon being poured out into the bowl again just to document some of these characteristics of the leaven because the leaven strength can have such an impact on the bulk fermentation of the dough after i added the starter you add in 700 grams of water now this is where i had to make a decision as to whether i continue to follow the tartine recipe which calls for 80 degree fahrenheit water which is 27 degrees celsius i did decide to do that because i wanted to give this a little bit of a jump start i could have mixed this entire batch of dough at 70 degrees fahrenheit or 21 degrees celsius it could have taken 14 or longer hours for this to double so because i don't want to be up in the middle of the night making this video i followed the tartine recipe with the water temperature it maybe gave this a little bit of a jump start but since then i had my room temperature at between 69 and 70 degrees fahrenheit it's cool in here it's about 21 degrees celsius 20 degrees celsius i have my doors and windows open here it's early spring in cleveland so if you hear the birds outside or we have a couple of geese out here in the back that like to announce their arrival and departure you might hear some different background sounds here today after we mix the dough we do a 30 minute auto lease again that's at room temperature but the dough temperature was still in the high 70s during the auto lease we were at 77 degrees fahrenheit dough temperature is 25 degrees celsius so a little bit of a jump start as i mentioned then we had 20 grams of salt 50 grams of reserved water mix that up again that dropped my temperature down to 76 degrees fahrenheit or 24 degrees celsius then i started doing stretch and folds every 30 minutes on the countertop here i'm on the fourth stretch and fold right now we're doing these at 30 minute intervals my room temperature is 69 degrees fahrenheit 20 20 degrees celsius my dough temperature is still at 71 degrees fahrenheit i want to get this down to 70. it'll be there momentarily that's 22 degrees celsius so at the fourth stretch and fold what's going to let's say we're roughly at the 70 degree bulk fermentation temperature i'm going to do the fourth stretch and fold i'm going to see how this feels i might do a fifth one then we're just going to pause and let i'll divide this into four separate bowls and then we're going to look for the first one to rise 30 and that'll be our first cutoff point and we'll compare that 30 percent rise and all the other volcanic criteria to see what a 30 percent rise lope looks like at 70 degrees fahrenheit or 21 degrees celsius because the 30 percent rise is the recommended rise in the tartine book based on our hypothesis that loaf is likely going to be under proofed because you're getting a little false sense of that rise at a lower temperature because the dough is stiffer but we don't know until we try it out and see if we can prove that so i'm going to continue to do all this off camera i'll come back when we get to that first batch of dough at the 30 percent rise then we'll do the bulkmatic test so while we're waiting for the dough to rise i just wanted to take this opportunity to introduce you to my production crew now here at the institute we have a state of the art facility for recording these videos and i'm the person on the camera that gets all the credit but i really have a tremendous team of people behind the scenes making all this happen so i wanted to take this opportunity to introduce you to my hard-working crew first we have my sound engineer rodney holding up the boom mic there he always makes me sound good next we have my cinematographer mickey you can see he only uses state-of-the-art recording equipment for all of our video the third member of our crew here is jason jason's our video editor he really works a miracle on the computer there making all this stuff look good and then lastly but certainly not least is our director the brains behind the operation jean-luc john say hello to the camera that guy's really a piece of work but i love him like a brother some people say we even look like brothers but honestly i don't see the resemblance thanks for meeting my crew let's get back to making some bread it's been seven hours since we mixed the dough there's not much happening here yet but what i'm going to suggest is let's go through the nine criteria of the volcamatic test and see where we are because this is the point where you start second guessing yourself your mind starts playing tricks on you you think you messed up the ingredients you think you forgot to add your starter maybe something was wrong with your 11 just go through the test let's do the nine criteria and just see where we are now the reason i'm not too worried about this even though this is a long time for me because i generally do shorter bulk fermentations is because i know from all my experience that bulk fermentation follows a curve that looks like this it nothing happens up front very very slow slow slow slow slow then it gets to a point and boom you get the hockey stick at the end where a lot of activity happens at the very end of the bulk fermentation process at 70 degrees fahrenheit this could be a 10 to 12 hour process that means that the the vast majority of this of the rise might occur in the last 90 minutes it's usually in the last 15 to 20 of the full bulk fermentation time is when you see that big move at the end so we still have a little ways to go but i like to look at the dough i like to smell it i want to get my hands on it and just get some data points here to see where we are at the seven hour mark so first our temperature we are at 70 degrees fahrenheit is my room temperature exactly where we want to be the dough temperature this one's at 69. this one's at 69. that one's at 69. that one's at 69. so our temperature is 20.6 degrees celsius 69 degrees fahrenheit one degree below where we want to be very much in the ballpark our time is at seven hours i'm just guessing based on some of the guidance that we saw in the recipes this could take 10 12 14 hours for these to rise so we're still early the percent rise if i look at my marker on my bowls i have these marked on my side in milliliters they are above the starting point i'd say they're at about i don't know maybe a 10 rise right now pretty consistently across all four of these are they domed on top they are domed a little bit on top you can definitely see some fermentation activity happening in these so i know that i didn't forget to add my leaven i know that my leaven is working are there bubbles on the top i see a little bit of bubble activity one two three that indicates that there's some fermentation happening but we're nowhere near done are there bubbles on the sides now this is really usually a good indicator of how far along we are there are very few bubbles on the side of these this dough still looks really flat to me i'm a little bit surprised that we're not seeing more bubble activity on the side that just means this is still super early then i do what i call the wobble test what i do is i like to shake the bowl and see how that dough moves in the bowl and if it starts what i call splashing against the sides of the bowl that means that there's aeration in here this is actually moving pretty well so this isn't as stiff as i might have thought but it's not loose and aerated it doesn't feel like there's a lot of air in it it just feels soft is the way that i would describe that then i want to do a window pane test i'm just going to randomly select one of these they all should be the same and the reason i do the window pane test is for two reasons one is to ensure that we got sufficient gluten development when we're mixing the dough that's a spectacular window pane right there look at that translucency right through that it's not tearing at all that's a superb window pane so that means that we have sufficient gluten development from the stretching and folding and from the inherent gluten that's in the flour and we're not seeing any evidence of gluten deterioration which is the early indication of overproofing so if you think for some reason your dough is overproofing just do a window pane test you'll feel it in your hands if that window pane starts to tear starts to fall apart starts to rip you know that the the gluten is starting to deteriorate that's going to happen very late in the process i didn't expect it to happen here but if you're ever nervous about it just put your hands on the dough do the window pane test that's a super way to really feel where your dough is really tactile then lastly we do the smell test and this is really fascinating because in the bulkimatic test there's a continuum of what i call a flowery smell which is when you just mix the flour and water you know that smell when you mix the dough that's when you're really significantly under proofed when the dough is fully proofed it'll usually take on a very sweet smell almost has a sugary smell to it some people call it a ripe smell i call it more of a sugary sweet smell at least with the flour that i use and when you start to over proof the dough it'll start to smell like your starter you'll you'll smell that vinegar smell coming out of it or maybe a little bit of alcohol smell but primarily vinegar what i'm smelling here in this dough is actually the sweet smell that i usually it's not quite there but it's tending towards the sweet smell that i usually smell in the 80 degree fahrenheit or 27 degrees celsius bulk fermentation when the dough is really nearing the end of bulk fermentation so this is really fascinating because just based on the smell this feels like it's really far along but none of the other variables are there the rise the bubbles etc so the smell is interestingly a potential false indicator at these low temperatures because it definitely is is leaning towards the ripe sweet smell that i look for so that's where we are with the test right now i'll put this up on the screen just so we have a record of where we are at this point we still have a ways to go i'll check in here from time to time and we'll see if things start moving here are the details of the balcomatic chart at seven hours it has been nine and a half hours since we mixed the dough loaf number one is at the 30 percent rise mark so what we want to do now is we'll go through the nine criteria on the bulkmatic system and what i want to do is compare a 30 rise at 70 degrees fahrenheit or 21 degrees celsius to a 30 percent rise at the normal tartine recipe which would be 80 degrees fahrenheit 27 degrees celsius so let's go through the test so obviously temperature we've been right at where we want to be 70 degrees fahrenheit 21 degrees celsius that's been our target we started out a little higher we went a little under i'm going to call that right at 70. the time nine and a half hours now that compares to the 80 degree loaf the tartine loaf typically bulk ferments in about four and a half hours so we are you know more than double the amount of time to get to that same 30 percent rise which is a bit surprising for a 10 degree fahrenheit difference that's about six degrees celsius difference that it would take twice as much time it's interesting i don't know what else to say about it at this point the percent rise we're cutting it off at 30. that's usually the high end of the range for tartine then we do the other criteria is the dough domed on top slightly there's a slight shoulder around the edges not as pronounced as i normally would see are there bubbles on the top very very few are there bubbles on the sides more than there were before but fewer than we normally would see in bulk fermentation at this point the wobble test that dough is somewhat loose but yeah not quite as aerated as it should be but i would call that somewhat loose it's shaking pretty nicely the window pane test we're really just doing this now to make sure that we're not heading into overproofing which i don't think we are still a really superb window pane so that says that this dough has further to go like you could really let this continue to ferment without any risk of overproofing based on the strength of that window pane and then the smell test i'm looking for that sweet smell that i smell in the peak point of bulk fermentation it's just slightly to the left of that i'm still smelling a hint of the flower smell not the total sweet smell that i'm looking for so other than the percent rise all other indications are that this loaf is not finished with bulk fermentation but we're really honing in on the percent rise so that we can do a strict comparison of a 30 rise of a 70 degree loaf to a 30 percent rise of an 80 degree loaf and this is just an indicator of what we'll probably see when we bake this up we never really know until we bake it and slice the loaves open so i'm going to call this done even though our indicators are saying that this is likely under proofed this is what a 30 rise loaf at 70 degrees fahrenheit 21 degrees celsius looks like here are the bulk-o-matic details for loaf number one we'll see how this bakes up tomorrow you can pause here if you want to look at that in more detail so if you haven't seen any of the seven prior episodes in this series let me describe what we do here because it's a little different because we're focused on the cutoff of bulk fermentation i really want to assess the crumb really at this point in time if i could so i don't do pre-shaping or final shaping because the shaping steps can introduce irregularity into the crumb that can sometimes be confused with over proofing or under proofing so i basically take this loaf out of the bowl i flop it into the shaping basket with no pre-shaping and no final shaping i still let it rest on the counter top for 30 minutes because the bulk fermentation step is done but according to the tartine recipe which is our baseline for all the experiments there's another 30 minute room temperature bench rest so we have to do that to stay consistent with the baseline recipe then this goes into the refrigerator for an overnight cold and then we'll bake it up in the morning so i'm basically just going to take this out of the bowl right now and flop it into that shaping basket now i like to feel what this dough feels like as it's coming out of the bowl this is stiff compared to what the dough usually feels like when it's coming out of the bowl this is a little bit stiff in the middle the edges of this actually feel kind of soft but in the middle i'm just feeling a very stiff mass of dough then i carefully scoop this out and i do what i call the droop test that's a pretty droopy loaf so that's pretty far along more than i expected and then we flop that into the shaping basket that's all we're gonna do and then once it's in the shaping basket i like to shake it yeah that dough is pretty far along actually for a 30 rise and based on the smell that loaf looks pretty good even though you know the a lot of the indications show that this might be under proofed and i think it probably is it's not seriously under proof that dough actually looks okay so i'm not sure what's going to happen with the future loaves here but this goes into the fridge for an overnight cold after a 30 minute bench rest we'll bake it up tomorrow so in the first part of this video we asked the question why do some recipes call for a 30 rise when others call for 100 rise and our hypothesis is that because those 100 rise recipes are bulk fermenting at a lower temperature and at a lower temperature the dough can just stand up to a taller rise the architecture of the gluten structure is not as relaxed as a warm dough that's our theory there's another component that you have to think about to understand why certain recipes may cut off at 30 percent like tartine versus 100 for the three samples that i i talked about earlier in the video so when a recipe designates the percent rise for bulk fermentation you always have to think about what happens after the end of bulk fermentation and this is part of the reason why tartine calls for a 30 rise and it cuts it off seemingly really early the reason is because in the tartine recipe after the 30 rise where the dough temperature is still at roughly 80 degrees fahrenheit or 27 degrees celsius you do pre-shaping and then you do a 30-minute bench rest during that 30-minute bench rest between pre-shaping and final shaping that dough is still actively fermenting at roughly 80 degrees fahrenheit because that dough temperature does not change significantly once it's at that temperature so i have 30 minutes of extra fermentation just because i called the end of bulk fermentation the yeast doesn't know bulk fermentation is over it's fermenting for 30 more minutes and then when the dough goes into the refrigerator here's a chart that i've shown in some other videos this is from a sample that i did a couple of months ago where i put a continuous probe thermometer into a loaf to look at the temperature of the dough after the dough goes into the refrigerator and what you see here was this dough went in at roughly 78 degrees fahrenheit or 26 degrees celsius it took an hour for that dough to get down to 70 degrees fahrenheit or 21 degrees celsius which is the temperature of this loaf so now think about that comparison in the tartine loaf we've been bulk fermenting at 80 degrees fahrenheit this one bulk fermented at 70 degrees fahrenheit at the end of the bulk fermentation step the tartine loaf goes another 30 minutes at 80 degrees it's really smoking that is a warm temperature and then when it goes into the refrigerator it's still above 70 degrees fahrenheit for an hour so for 90 minutes after the end of bulk fermentation this loaf of bread is still fermenting more vigorously than this loaf that's the reason for the 30 rise because you're trying to stop a speeding train when your dough is fermenting at 80 degrees fahrenheit 27 degrees celsius or higher you need to really slam on the brakes to get that to slow down so that's the reason that it cuts off at 30 percent is because you're hitting the brakes at 30 because it's bulk fermenting for 30 more minutes on the countertop and then another hour in the refrigerator before it gets to 70 which is the equivalent of this but then it keeps fermenting even after that if you look at this chart again it takes four hours until the loaf gets down to 50 degrees fahrenheit or 10 degrees celsius so the loaf is still actively fermenting in the refrigerator but when you just compare the two loaves 70 degrees versus 80 degrees there's clearly an extra 90 minutes of fermentation at a very warm temperature in this slope versus this low that's the reason you get the early cut off of the 30 it has been 11 hours since we mixed the dough loaf number two is done this is our 50 rise we are just at 50 right now let's go through the nine criteria on the bulk o-matic system first what's our temperature room temperature is 71 degrees fahrenheit the dough temperature is now at 71 so this is crept up a little bit that's 22 degrees celsius we were shooting for a temperature of 70 degrees fahrenheit the percent rise as i said is 50 percent that's higher than the typical recommended rise in the tartine recipe is the dough domed on top it is this is a little more dome than loaf number one you can see that shoulder around the edges when i tip the bowl like that are there bubbles on the top yes there's one big bubble here one two three small bubbles so a little bit more vigorous bubble activity on the top of this one than the prior loaf are there bubbles on the side yes this is where i'm seeing a significant difference compared to the prior loaf it's a lot of small bubbles usually we'll see more big bubbles on the side but just the number of the bubbles is much greater than loaf number one the wobble test this is more loose and aerated than loaf number one i'd say this is more typical with what i would see in a loaf that looks like it's about done let's do the window pane test to see if we have any gluten deterioration and we do not that that is still a fabulous strong translucent window pane after 11 hours that's incredible and lastly the smell test this is smelling more like that sweet smell that i'm looking for still slightly to the left of it i'm still smelling a hint of the flower smell and not that pure sweet sugary aroma that you almost taste on the tip of your tongue through your nasal cavity so this is an interesting loaf at 50 rise this looks a little bit more like the standard tartine loaf would be at 30 at the higher temperature but this is still slightly under what i would expect based on the bubbles that i'm seeing on the side the bubbles on the top so we're still not quite there so let me put this up on the screen so you have the details of the bulkmatic chart for this loaf the fascinating thing here is that window pane after 11 hours we're still seeing no gluten deterioration at all that is really the magic of fermenting at this low temperature of 70 degrees fahrenheit 21 degrees celsius at the higher temperature we start to have gluten deterioration when we when we bulk fermenting tartine at 80 degrees fahrenheit 27 degrees celsius you'll get gluten deterioration after five hours the dough will start breaking up in your hands and that's because the acidity of the loaf increases with the temperature the acidity stimulates the protease enzyme the protease enzyme eats the gluten the protease enzyme is asleep here it's just not present because it's not breaking down the gluten i don't see any evidence of it so this is really like i said the magic of this low temperature fermentation is there's no gluten breakdown let's take this out of the bowl and get it into the shaping basket yeah this feels more aerated than the prior loaf i can just tell by the way it's pulling away from the sides then we scoop it out yeah this dough is soft there's our droop test that looks very similar to what we would see with 30 percent loaf at 80 degrees fahrenheit with tartine and then we do our shake test that's a really nice shake there's a lot of air in that dough really nicely fermented i think that would be a really nice looking loaf based on what i've typically seen in the past that's a 50 rise okay let's get this into the refrigerator after i do the 30 minute bench rest this will go into the fridge for the overnight cold we'll bake it up tomorrow it has been 12 hours since we mixed the dough this is loaf number three this is done at a 75 rise that's looking pretty good so this is just one hour after loaf number two so as i mentioned earlier there's kind of a hockey stick effect here with the bulk fermentation once it really starts moving it starts moving very quickly so nothing happened for nine and a half hours then we had loaf number two at 11 hours loaf number three at 12 hours and we'll see if loaf number four is right on the heels of this one let's do the bulk-o-matic test let's take the temperature this dough temperature is at 69 degrees fahrenheit versus our goal of 70 that's 20.6 degrees celsius versus 21.1 so right where we want to be this has really been very tight in that range the whole time the time as i mentioned 12 hours since we initially mixed the dough the percent rise is at 70 percent is the dough domed on top absolutely you can see each one of these successive loaves is getting a higher rounder dome on the top are there bubbles on the top yes i see one two three four five bubbles on the top of this one that's more than we had on the others are there bubbles on the side yes this is really the vigorous bubbling that i typically look for in bulk fermentation you can see that on the side of the bowl let's do the wobble test and you can see this low is loose and aerated this one looks very much like a nicely proofed loaf the window pane tests our gluten after 12 hours typically we would see some gluten deterioration not with this dough this is incredible 12 hours and i'm not seeing any tearing of that dough that is a spectacular window pane it's unbelievable after 12 hours as i said that is really the magic of this low temperature bulk fermentation there's no gluten deterioration at all and then the smell that's the sweet smell that i look for all of these loaves though have been slightly left of center if you will slightly less of that sweet smell than i smell with the slightly warmer bulk fermentation at 80 degrees fahrenheit or 27 degrees celsius that's just something a little bit different about that we'll see how these bake up and how they taste so let me put this up on the screen so you have the details of the bulkmatic chart for this loaf now let's see how this feels as i take it out of the bowl very nicely aerated loaf similar to the prior loaf i'm seeing a little bit of those gluten strands around the edges but they're pulling away pretty easily it's not a real sticky loaf like i see when loaves start to over proof this one feels slightly airier than the last one which makes sense because it rose 25 percent more there's our droop test that still is not a bad looking loaf these are not indicating enter any overproofing at all into the basket the shake test really beautiful that looks like a really nicely proofed loaf i think that one's going to bake up very nicely as well i like the way that that's shaking right there so this will go into the refrigerator for the overnight cold with the others and we will bake this up in the morning it has been 13 hours since we mixed the dough loaf number four is done this has doubled in volume it's right at a 100 percent rise and one of my pet peeves with these recipes that call for a doubling of the dough is that people just try to eyeball it sometimes there's no way you could just look at this bowl and tell the difference between 100 rise and 75 percent rise or 125 percent rise you really have to measure it and it can make a material difference as i think we're going to see in this one the difference between 75 and 100 percent was one hour difference and this dough looks and feels a little bit different to me already so let's go through the tests number one is our temperature 70 degrees fahrenheit right on the target 21.1 degrees celsius exactly where we wanted to be we did a great job maintaining this temperature throughout so i think this is a really great test at the target temperature the time 13 hours from the time we mix the dough the percent rise 100 or doubling is it domed on top this loaf is domed on top but you can see it actually looks like it's flattening out a little bit around the edges compared to the last one are there bubbles on the top this is peculiar because this had some bubbles on the top and they've deflated so that implies that this one is starting to push towards overproofing a little bit i don't actually see any bubbles on the top and i know there were some on the top earlier are there bubbles on the side there are i would say this still has vigorous bubbling on one side but the other side is starting to lose its bubbles you see those tiny pinpoint bubbles on that side so the bubbles on the side are deflating the wobble test loose and aerated it's hard to tell anything good or bad about that that's right down the middle really nice loose loaf very aerated let's do the window pane see how our gluten is standing up 13 hours after mixing the dough wow still just incredible window panes pulling on this dough look at that it is fabulous just never seen anything like that 13 hours into bulk fermentation no tearing at all and then smell test very similar to the others heading towards that sweet smell in the middle but not quite as sweet as when i bulk fermented at warmer temperatures still just slightly left of center but this so this loaf still looks pretty good let's get it out of the bowl i can't really tell where this is until i feel it now this is super aerated it's just like a giant puffy marshmallow at this point the dough starts to feel what i call fragile where like every time i'm touching this it feels like i'm degassing it so i'm trying to be super careful see if i can get this out wow that is really an airy loaf in our droop test you can see that is drooping much more than the other ones that one's actually stretching in my hands that loaf is losing a little bit of structure but wow that is a super aerated loaf look how that's sitting up in the pan super aerated we'll see how this picks up this is this will be a real interesting one because that's got a lot of air it's starting to push towards the right side of the volcamatic indicators indicating it could be over proofing but the gluten strength is holding up tremendously well in that window pane so this is just a peculiar combination of factors that i haven't seen before so i'm glad we're doing this test let me just put the indicators up on the chart so you have this for the record and you can see where this one is pushing to the right a little bit more than the prior ones we're going to let this sit on the countertop for its 30 minute bench rest and we'll bake this up tomorrow and see how all these look it's the morning of day two i'm preheating the oven it's time to score and bake the loaves now i'll do this off camera in the interest of time there's not a lot to see here until the loaves are baked but just for the record in case you're trying to replicate this process in your home what i do is i preheat my dutch oven in the oven to 500 degrees fahrenheit that's 260 degrees celsius i then put the loaf into the dutch oven with the lid on i reduced the temperature to 450 degrees fahrenheit or 232 degrees celsius i bake it with the lid on for 20 minutes then i remove the lid continue baking at that same temperature for 15 more minutes these loaves typically bake up in about 35 minutes total and if you recall this was a thousand gram recipe divided into four small loaves so these are 250 gram flour weight loaves each they bake up in about 35 minutes as i said each of these lobes spent 12 hours in the refrigerator my refrigerator temperature is 36 degrees fahrenheit or about two and a half degrees celsius that's pretty cool temperature but if you saw from that chart yesterday it takes almost 10 hours for the loaf temperature to get down to the refrigerator temperature so there's still fermentation going on in the refrigerator in that cold i put the lobes into the refrigerator at different intervals based on it when they were done in bulk fermentation i'm taking them out at the same interval so they all will have exactly the same cold time of 12 hours after i take them out of the oven i will cool them and then we'll come back here and cut them open and inspect the crumb and see what we can learn about this experiment the lobes have baked and cooled before we proceed let me just recap the experiment so the idea behind this was to try to replicate the tartine loaf bulk fermented at 80 degrees fahrenheit 27 degrees celsius typically for four and a half to five and a half hours and a 30 percent rise in the dough now the idea was to replicate that type of loaf at a different bulk fermentation temperature of 70 degrees fahrenheit or 21 degrees celsius so what we did was we baked four loaves all bulk fermented at 70 degrees fahrenheit 21 degrees celsius we maintained that temperature really consistently throughout the process and then we chose different percentage rises here to try to compare which percent rise at that lower temperature is the equivalent of the 30 percent rise at the higher temperature so loaf number one we rose thirty percent which is the typical guidance from tartine that bulk fermented in nine and a half hours loaf number two rose 50 after 11 hours of bulk fermentation loaf number three 75 percent rise after 12 hours of fermentation and loaf number four 100 rise or doubling in the dough after 13 hours of bulk fermentation after these bulk fermented they did a bench rest of 30 minutes which is exactly the same as what we do in tartine after we reach the 30 target then all the loaves went into the refrigerator for a 12-hour cold my overnight refrigerator temperature was about 36 degrees fahrenheit or 2.2 degrees celsius so this is a very controlled experiment relative to the time temperature in percent rise and before we proceed let me just remind you that these loaves have no pre-shaping and no final shaping this is basically bulk fermented dough that i scooped out of the bulk fermenting bowl i flopped it into a shaping basket it sat overnight in the refrigerator i scored it and baked it up this morning it's extraordinary how good these loaves always look i say this in every one of these videos bulk fermentation makes the bread i mean just look at this look at the ear look at the height look at the symmetry and shape of that loaf it's just extraordinary that you can get that out of bulk fermenting dough with no shaping here's a the shaping baskets that i use some people have asked how i do this i basically use these loaf pans but these are a little bit big if you're just doing 250 gram flour weight loaves which is what these are so i use these inserts i just made these wooden inserts in my shop to just basically reduce this down into a rectangle i'm not even using banatons it's basically a geometric type of rectangle and then i put a tea towel in here with the flour on that and they all ferment them or cold them overnight in the refrigerator in those baskets i flop them out in the morning i score them and this is what you get it's amazing so now let's just look at these from the top down and see what we have loaf number one thirty percent rise fifty percent rise seventy five percent rise a hundred percent rise you kind of see the progression that you would expect the the shorter bulk fermentation time nine and a half hours eleven hours twelve hours thirteen hours the loaf proofs less it's more compact a little bit tighter when you get up here to 13 hours 100 percent rise the dough is a little bit more relaxed the loaf is a little bit more relaxed that's a typical pattern that you would expect and that we often see in these experiments so let's look at loaf number one look number one 70 degrees fahrenheit 21 degrees celsius bulk fermented for nine and a half hours 30 percent rise in the dough there's a gorgeous loaf i mean it's a little compact but we got a beautiful ear there really nice shape to that loaf but the one thing i'm a little concerned with here is that little bubble on the top that ridge right there is sometimes an indication of under proofing because you'll get a little gas bubble right under the bloom this one looks a little bit under fermented to me just looking at it from the top down because it's kind of a compact loaf loaf number two this one really looks beautiful this opened up a little bit more than loaf number one so a little bit less compact beautiful ear nice bloom on the ear there beautiful symmetrical shape that looks like a very nice loaf that one rose 50 percent and it took 11 hours to get there now when we get into loaf number three and four as you can see from the top down here these look a little bit more relaxed they started to lose their shape a little bit and you can really see that tight symmetrical shape of loaf number one which might be under proofed as you get into more fully proofed lobes the 75 rise and the 100 rise that does relaxed a little bit more and you see the way these are spread out around the midsection and a little bit oblong in their shape so let's take a look at loaf number three this one is interesting again really nice height not as pronounced of an ear and you can see on the top here there was a little bit of a blowout in the skin in the crust right there which sometimes indicates that the dough is starting to over proof because you're getting a little bit of gluten deterioration loaf number four looks very similar to loaf number three to me it actually has a little bit of a taller ear but i'd say loaf number four that's our hundred percent loaf doubled in size really nice looking loaf right there a little bit irregular shape but not bad the other thing you notice looking from the top down is the color and this has to do with the amount of fermentation time the longer you bulk ferment the more sugars come to the surface of the loaf and you get this my yard reaction or this caramelization that dark mahogany color on the loaves they've all fermented longer so you can see loaf number one is a little more blonde loaf number four is a little more dark these baked up in the same dutch oven at exactly the same temperature same time same preheating time between each loaf so i think this is literally due to a different chemical reaction in these lobes three and four because they bulk fermented longer and they darken a little bit because of that there's an interesting kind of break point between loaf two and loaf number three so this is our fifty percent rise versus seventy five percent rise 11 hours versus 12 hours and you can see loaf number two still remains really compact and symmetrical which tends to show that that's more on the under proofing side and then when the loaf gets relaxed oblong this bulge on the side the tearing of the crust here implies that it's leaning towards overproofing so there was definitely a break point here between the 50 rise and the 75 percent rise or the 11 hour mark and the 12 hour mark at 70 degrees fahrenheit 21 degrees celsius bulk fermentation let's see what these look like when we cut them open so now it's time to cut the loaves before i do that i just want to recap the experiment was basically to find which one of these four loaves looks the most similar to the classic tartine loaf with the 80 degree fahrenheit 27 degrees celsius bulk fermentation and a 30 rise in the dough i know i've been talking about this the whole time and holding this book up and you're like i don't know what he's talking about here's a picture of a classic tartine loaf fully proof beautiful loaf i've done this a hundred times this is from a prior experiment this is what we're trying to match with the four loaves that we baked this morning so you can see here just that beautiful shape the ear opened up really nice height very consistent proofing end to end top to bottom and a little bit of an open irregular crumb that's kind of the classic tartine look that we're trying to find now that photo was from an experiment i just did a couple of weeks ago so these loaves are literally exactly the same the same flower maybe even the same bag of flour the same water the same dutch oven the same lineage of starter these are as close to an exact comparison of loaves as you can get let's cut open loaf number one and take a look so this one rose thirty percent the same as the tartine loaf but this went for nine and a half hours of bulk fermentation versus typically five and a half hours for the tartine loaf and this bulk fermented at 70 degrees fahrenheit versus 80 degrees fahrenheit or 21 versus 26 degrees celsius let's see what the crumb looks like now that is a pretty nice crumb it's slightly under proofed but not bad when i see these kind of vertical bubbles coming up here off the bottom that implies a little bit of under proofing but really not bad that is actually a pretty nice very similar tarte classic tartine loaf to what i would get before just a touch under proof compared to that benchmark loaf that i just showed so this is really interesting because basically we're saying that a 30 percent rise at 80 degrees fahrenheit is very similar to a 30 rise at 70 degrees fahrenheit if you just give this enough time nine and a half hours versus five and a half hours it got pretty close but not quite exact let's see what the next one looks like before we make a call here's a more detailed look at that crumb if you want to pause here loaf number two 50 rise 11 hours bulk fermentation at 70 degrees fahrenheit 21 degrees celsius this is a little bit taller low a little bit more air as i'm cutting through it now ignore that big air bubble at the bottom because we did not do shaping of these loaves you're going to get some air bubbles like that now this one is more proof than the prior one you can see that i don't have those big vertical tunnels coming up from the bottom that's a pretty good looking loaf i think that actually looks very similar with the exception of that air bubble to the benchmark loaf really close so this is basically a 50 rise in the dough that i think is closer to the tartine 30 percent rise this one went 11 hours versus tartine 5.5 so roughly double the time at 10 degrees less temperature fahrenheit 6 degrees less celsius here's a more detailed look at that crumb if you want to pause here loaf number three this one looks a little more relaxed to me feels a little softer to the touch let's see what it looks like [Applause] really nicely proofed loaf now that again i got a big air bubble here ignore that that's what i would call a fully proofed loaf we've kind of gone past that open irregular crumb and now you're really getting a little bit more dense crumb top to bottom side to side this is just past the point of of what i call fully proofing heading towards overproofing this is kind of fully proofed plus if i had to put a name on this so this is what a 75 rise looks like at 12 hours of bulk fermentation as i look at this this actually looks very similar to an 80 degree fahrenheit tartine loaf at a 40 percent rise looks very similar to the 70 degree fahrenheit loaf with a 75 percent rise so i'll i'll see if i can find a picture here's a picture of that loaf i was referring to this is a 40 rise tartine loaf versus the 75 rise at 70 degrees fahrenheit that's a great comparison here's a more detailed look at that crumb if you want to pause here loaf number four very fully proofed loaf again pushing up to the edge of overproofing but i wouldn't call this overproofed in any way but you've lost that open irregular crumb you have a much more dense crumb throughout so this is again what i would call a fully proofed plus this is pushing up against over proofing but not really you can't really call this over proofed because it kept its shape beautifully but you can see the real dense cells here which imply that this is kind of past its prime some people like a really fully proofed crumb like this but we're trying to compare this back to that classic tartine open irregular crumb this is really fully proofed plus similar to loaf number three so this is the hundred percent rise or the doubling of the dough and this gives you a very fully proofed loaf but still a very nice shape to it here's a more detailed look at that crumb if you want to pause here now this hundred percent loaf at 70 degrees fahrenheit looks a lot to me like a 60 percent rise loaf under tartine you really need a photographic memory to do this i hope i can find the pictures that match this so i just jotted down my notes here based on my initial reaction to these loaves and it's fascinating because i'm comparing in my mind to the 80 degree fahrenheit 27 degree celsius tartine lobes as my reference point so let me just lay these out and i'll see if i can put these into a chart so i went back to some prior videos and photos and i essentially found pictures of loaves that look exactly like the four loaves that we baked today using the standard tartine method for those prior loaves and based on those details here's how they compare so for today's loaves which you see in the left hand column our 30 percent rise loaf today looks like a standard tartine loaf with a 25 percent rise our 50 percent rise loaf today looks like a tartine 30 percent rise our 75 percent rise loaf today looks like a 40 percent tartine rise and our 100 percent rise loaf today looks like a 60 percent tartine rise and then the third column you see the difference in the number of percentage points between those two values so let's go to the next page and what this shows is the data points now plotted on the two lines the blue line are today's four lobes with their percent rise and then the red line are essentially the matching crumb photos and looking at what percent rise in those tartine lobes got the matching crumb to today's lows so here you can see the difference between those two charts grows as the percent rise grows it becomes a wider variance but the fact that there is a significant difference between the blue line and the red line is a proof of our linguine test that basically says the blue line the cooler bulk fermentation temperature requires a higher percent rise to deliver the same results versus the red line which is the the warmer bulk fermentation temperature that's because as we discussed in that red line the gluten matrix is relaxed so it's sitting down in the bowl it's not rising as much the protease enzyme starts to deteriorate the gluten and the third factor is because the loaves continue fermenting after you finish bulk fermentation so that gap continues to close slightly when you're bulk fermenting a warmer loaf versus a cooler loaf and then lastly on this page i just summarized the percent rise and the bulk fermentation times for the eight loaves that i'm comparing so these are the four loaves now i sliced four slices out of each one to see if there was any more story to tell in the crumb and all i can say is wow these loaves look spectacular all four of them just amazing and let's just recap how wide of a variation there was in tem and time and percent rise nine and a half hours 11 hours 12 hours 13 hours that's a four and a half hour difference between this loaf and this slope i mean it's unbelievable how similar those are so working at this low temperature you have a massive massively wide margin of error in really trying to catch the end of bulk fermentation you have a four and a half hour difference between loaf one and loaf number four it's unbelievable and then when you look at the percent rise 30 percent 50 75 100 the difference between a thirty percent rise and a hundred percent rise i mean i can definitely see the difference here but that is really an extraordinarily tight band of how the crumb looks now if i take a more critical look at this kind of going left to right as i said when we look at the outside of the lobes there's definitely a break point between loaf two and loaf three where you go from this open irregular chrome on loaf number two to this more dense kind of honeycomb style crumb on loaf number three which to me implies that you're heading into overproofing territory but the difference between these lows these low temperature loaves at 70 degrees fahrenheit 21 degrees celsius is over proofing is creating a little bit of a dense crumb here as you see in this one and this one for example but it's not really deteriorating the loaf the way that you get overproofing at a warm bulk fermentation of 80 degrees fahrenheit or 27 degrees celsius at a warmer temperature you get that protease enzyme effect where these what i'd say over proofed loaves really start to deteriorate in terms of the gluten structure the lows will flatten the crumb will change its texture significantly differently from these here because we're bulk fermenting at a lower temperature you keep the protease enzyme at bay you don't get the gluten breakdown it's as simple as that you could have probably gone past 100 percent and still had a decent looking loaf that's the ken forkish recipe where he recommends a 200 percent rise or tripling in size of the dough i can see that now because at that low temperature you just don't risk the gluten deterioration so we have completed a taste test of the four loaves i've tasted them all and i employed the services of an independent judging panel that would be my wife who also tasted them all she tastes all my bread both of us really came to the same conclusion that among these four loaves there was really no difference among the four thirty percent rise tastes the same as a hundred percent rise nine and a half hours of bulk fermentation tastes the same as 13 hours of bulk fermentation that's not uncommon in these taste tests normally the variations in bulk fermentation time really don't produce a lot of flavor differences comparing this to the other lows it was very difficult to really put our finger on that without doing a side by side comparison at the same time i'm kind of going from taste memory if you will but to me the tartine loaf had a slightly more wheat forward flavor than these loaves these tasted incredibly mild to me and you know these also had a 12 hour cold which is typical with what i do with tartine and these might have had a slightly brighter acidic tang to them than the tartine lobes but like i said we really need to do a side by side comparison to be certain so when i think about bulk fermenting at 70 degrees fahrenheit versus 80 degrees fahrenheit it's not just a difference in the temperature it's a whole different style of baking sourdough this is entirely different style of making sourdough than i've done in the past where i was always at higher temperatures this is easier it's slower and it's much less risk now i've also bulk fermented at 90 degrees fahrenheit or 32 degrees celsius because i try to create tools for warm weather bakers people who are trying to bake in the summer people who live in warm climates year round 90 degrees fahrenheit is a whole nother level of extreme so what i did is i put this chart together that i call the 70 80 90 model and this is in fahrenheit because in celsius this would be 21 27 and 32 which doesn't quite roll off the tongue as easily so stick with me on this one for the people who don't use fahrenheit the 70 80 90 model so i really describe these as three completely different baking styles this isn't just a small tweak of the temperature there's a step function here when you go from 70 to 80 and 80 to 90 in terms of the way that you're baking or bulk fermenting the loaves so i just put a couple of categories down here and let me just walk through these the first one is that what i call the risk rating is that if you're a beginner and you're trying to figure out how to how to bake bread at 70 degrees it's like riding a bicycle 80 degrees is like riding a motorcycle and 90 degrees is like speeding on a motorcycle with no helmet so next when i talk about the baking style the 70 degree loaf is kind of a walk away loaf you mix the ingredients and you disappear for 8 10 12 hours that's a real typical overnight type of recipe for the tartine method you're typically using a proofing chamber to try to keep your temperature at that 80 degrees fahrenheit so that's what i call an attended style baking you can't really walk away from a tartine bulk fermentation you have to kind of stick with it and then for the 90 degree baking that is really a close monitor bulk fermentation where you're literally watching that in 15 minute increments and i've done it before it's very challenging and then i show the time ranges here where you have to have that contiguous bulk of time to finish bulk fermentation that's the challenge with the 70 degree bulk fermentation is if it's going to end 14 hours later you have to make sure that you're not sleeping or you're not at work or you're not away so you have to really time that big window to be able to make sure that you're around for the start time and the end time it's the only thing tricky about this but it really lends itself to overnight the risk of over proofing with 70 degrees is extremely low i mean i would have to try very very hard to overproof the slope i don't know how far i would have had to go over proofing risk with tartine is pretty moderate which i say you know 25 30 percent of the time you can overproof that loaf by accident really even if you're good at it and then at 90 degrees fahrenheit the overproofing risk is extreme i've done that before under proofing risk with this loaf i would say is moderate and and some people might look at this and say well that's not symmetrical with the overproofing because shouldn't it say that the risk is high or if you'd expect it to go high moderate low there's not a high risk of under proofing this because all you have to do is look at the dough i mean it's not that complicated if the dough hasn't risen keep going the risk of under proofing tartine seems to be about the same you really have to rely on that percent rise in anything below 30 percent rise is going to underproof so that's fairly equivalent under proofing on a 90 degree loaf is low just because it proves so fast so then you talk about the margin of error which means if i'm really trying to catch this exactly at that end of what i what i see here in loaf number two which is my desirable end point my margin of error is plus or minus two hours i'm really not going to screw up the loaf if i'm an hour earlier or two hours later there's a wide margin of error around this with tartine that margin of error is about 30 minutes you can see that in episode 1 of this series where i do 30 minute cutoffs and the nature of the crumb changes materially when you're bulk fermenting in 80 degrees and at the 90 degree loaf that margin of error is 15 minutes literally the loaf can change that quickly so then when you think about the total time required the 70 degree baking even though it's easier it requires two or more days you really can't do this as a same day low for even as a one and a half day loaf it's pretty much a two full two day process with tartine you can do that in the same day you can do a same day loaf or you can do an overnight cold and be a day and a half later and then with the 90 degree loaf similarly that's a one to one and a half or two day loaf and the skill level 70 degrees fahrenheit a beginner can do this mix the ingredients watch the dough try to pick some point between a 30 percent rise and a hundred percent rise it's not very difficult and you get a pretty good looking loaf that's what i would call beginner level skills for sourdough tartine is moderate level skills because you have to catch that cut-off point a little closer and baking at 90 degrees or bulk fermenting at 90 degrees fahrenheit is expert level because you're down in 15 minute increments with massive risk of overproofing bulk fermenting at lower temperatures is a lot easier than bulk fermenting at higher temperatures it's much harder to screw it up i mean there's a four and a half hour difference between these loaves and they all look pretty good there's a 70 difference in the percent rise they all look pretty good you have nowhere near that level of latitude when you're bulk fermenting at 80 degrees fahrenheit or 27 degrees celsius things would go south in a hurry so this has really been a revelation to me because i i've bulk fermented some loaves at 75 degrees fahrenheit for 24 degrees celsius and that's not materially different when compared to bulk fermenting at 80 degrees fahrenheit that extra 5 degrees when you get down to 70 degrees fahrenheit 21 degrees celsius everything just kind of slows down it's a lot easier it's less risky it's much harder to screw it up so if i were a beginning baker or advising beginning bakers i would definitely recommend starting with some of these cooler bulk fermentation temperatures what i call the low and slow method 70 degrees fahrenheit but it might take 10 12 14 hours for the loaf to to finish bulk fermentation that's really the only downside of using those recipes is i feel like they're a little bit less predictable in terms of the timing because you have to wait an hour to get from this loaf to this loaf and an hour to get from that one to that one so if you're really trying to fine-tune your chrome and find that perfect cutoff point it's a little more difficult because it's in a much wider window of time but conversely if you're just trying to get a decent crumb you have a massive window i mean you could over a 13 hour bulk fermentation you have a four and a half hour window at the back end of it to catch any one of these four lobes which are perfectly acceptable lows so what's the bottom line what did we learn in this video at the beginning of the video we asked the question how can some recipes call for a thirty percent rise in other calls for a hundred percent rise and they both come out the same the difference is the bulk fermentation temperature when you're bulk fermenting at lower temperatures 70 degrees fahrenheit 21 degrees celsius the dough can handle a much higher percent rise because you don't get that softening or relaxation of the gluten so that architecture of the gluten will stand up taller as we showed in the linguine test and the second thing is that when you're bulk fermenting at lower temperatures you have much less risk of stimulating the protease enzyme which starts to break down the gluten and it'll cause the loaf to start to collapse at the same time that you're trying to rise the loaf so warmer dough will generally just be flatter than cooler dough during bulk fermentation for those two reasons the other reason that some recipes call for a lower percent rise is because you have to consider what happens after the cutoff for bulk fermentation and this is a great example with tartine where we cut off bulk fermentation at a 30 rise because there's a 30 minute bench rest between pre-shaping and final shaping at 80 degrees fahrenheit and then the loaf goes into the refrigerator for the cold at 80 degrees fahrenheit it takes an hour for that temperature in the refrigerator to get down to 70 degrees so just those two factors alone are essentially adding 90 minutes of fermentation time at the 80 degree warm temperature 27 degrees celsius with tartine versus a 70 degree loaf that would say at the end of the 70 degree bulk fermentation you just shape it and put it into the refrigerator with no bench rest and it goes into the refrigerator at 70 degrees fahrenheit you've shortened that bulk fermentation time by 90 minutes by comparison to tartine so the early cutoff in the tartine method is what i characterize as you're trying to stop a speeding train because it's fermenting very quickly at that warm temperature you have to cut it off early because it's going to keep fermenting at that temperature before the refrigerator temperature gets it down into the point where it's retarding the fermentation and then lastly bulk fermenting at 70 degrees fahrenheit 21 degrees celsius i originally thought that this was just going to be some formulaic tweaking of the temperature charts it's really not it's a completely different style of making sourdough bread it just behaves entirely differently because you don't get the gluten deterioration during bulk fermentation that you see at warmer temperatures so it gives you a massive window to complete bulk fermentation in and it gives you a huge margin of error around the edges of what you're trying to achieve because it's extremely difficult to over proof a loaf at 70 degrees fahrenheit and it's difficult to under proof a loaf at 70 degrees fahrenheit because the dough just won't rise if you at least wait for the dough to rise to 30 percent for example it actually produced a pretty good loaf so bulk fermenting at lower temperatures is just another tool in your tool kit as a sourdough baker it just gives you another way to bake bread another way to modify your schedule and a way to de-risk your baking just to make it a little bit easier on yourself and still produce fantastic bread thank you for watching this video now i am going to eat some bread you

Channel: The Sourdough Journey

Views: 20,379

Keywords: sourdough, overproofing, underproofing, proofing, when is bulk fermentation done, how to you tell, cucuzza, cleveland, chad robertson, tartine, country bread, temperature, fermentation, starter, tom, crew, meet the crew, DDT, Temperature, Linguini, Linguini example, how to bulk fermentation work, end of bulk fermentation, when does bulk fermentation end

Id: HTKrdSOUJWs

Length: 85min 4sec (5104 seconds)

Published: Sat May 01 2021