The Fresh Loaf

News & Information for Amateur Bakers and Artisan Bread Enthusiasts

Tip - Maurizio discusses Evaluating the Bulk Fermentation

DanAyo's picture

Tip - Maurizio discusses Evaluating the Bulk Fermentation

This was posted as a reply in another post. It is so important it seems good to place it in a dedicated topic.

”I'm a bit late to this thread, but I thought I'd drop my two cents. Some incredibly insightful thoughts here on this topic -- a topic I consider to be one of the most challenging aspects to baking sourdough (and all bread, I'd assume): determining when to call bulk fermentation quits. Doc.Dough had a high point at the outset: how do we measure this quantitatively? There are so many conditions with each batch of dough it's hard to compare results baker-to-baker because we're all using a different flour, different starters, different mixing methods, vessels, and so much more. Because of this, when I talk to other bakers or do a post to The Perfect Loaf sharing a formula I'm working on, I don't specifically list a percentage rise to indicate when bulk fermentation is finished. Instead of using rise as an indicator, I like to judge when bulk completes through other signs:

  1. a significant rise in the dough from the beginning of bulk to the end
  2. a smoothing of the dough's appearance
  3. increased elasticity when tugging on the dough
  4. domed edges between the dough and the bulk container
  5. other signs of significant fermentation: bubbles on top and sides, and if you're using a clear container, bubbles on the bottom as well

So, many of the above are quite nebulous, but there's enough between all of those, plus experience with a particular dough, to give me a ballpark for when to end bulk fermentation.

Regarding #1: I say "significant" because I want to see some rise in the dough indicating fermentation and dough strength (a weak or overly wet mixture won't ruse much), but I don't measure the percentage rise explicitly. Why? In my experience, it can lead to false conclusions, especially if you're switching formulas frequently (which I am regularly doing). For example, a highly hydrated 100% whole wheat dough won't rise to the same height as a mostly-white formula. Therefore, saying 50% rise and trying to use that yardstick for both doughs is like comparing apples to oranges. One caveat here is if you are doing the same formula day after day, in this case, you can likely conclude percentage rise.

Numbers 2, 3, and 4 above all point to dough strength, which for me, is the number one indicator overall. As we know, a dough is strengthened not only through mixing/kneading/stretch and folds but also through fermentation as acids created as byproducts have a strengthening effect on gluten. It's easy to see this: observe your dough through the course of bulk fermentation: at the beginning, it's shaggy, sloppy, loose, and at the end, it's smoother, silky, and elastic.

Domed edges between the dough and bulk container sides further indicate strength as the gasses produced during fermentation push the dough upwards, and the center tends to dome slightly toward the outside. I also wanted to state that for me the final dough temperature (FDT) sets the stage for bulk timing. If I'm working on a mostly-white dough with typical levain percentages (10-20%), I can almost approximate when I stop bulk fermentation based merely on what the dough temp is after mixing. If I'm close to 80°F: I better start checking my dough around 3-3.5 hours; if I'm close to 75°F: it's likely going to push out to 4-5 hours. I'll use this as my coarse compass, and then from there, I use the numbered items above to further assess the dough in the moment to determine when to divide.

One thing to keep in mind here is the flour used in a formula and the hydration will drastically change bulk fermentation times and can throw a wrench into things. For instance, if I'm working on a 100% whole wheat dough at 105% hydration, the dough will have an almost flat surface in the bulk container all the way to divide time. Additionally, it may not rise all that much at all.

So to sum up, determining when to end bulk for me is much like what a (good?) doctor might do. I need to look at everything through a holistic lens to conclude: look at all the clues (the numbered items), any data collected (in our case formula and FDT), and experience to give my patient a diagnosis (when to end bulk).

Even with all this, there are plenty of times I still go to dump my dough container and find the bottom of the dough super, super active and kick myself for not tending to it 30 minutes earlier.

That's my approach to bulk fermentation. I know many bakers who use volume increase, and that's just fine, as is right with just about everything in baking: it's all about what you're used to and what works for you :)”

albacore's picture

Thanks Danny; I would add that the float test can also be a useful indicator on the progress of a bulk ferment.


DanAyo's picture

Lance, I have never heard of the float test used for ending the bulk ferment. I always thought the float test was sed with starters. That’s a new one for me.

barryvabeach's picture

Dan,  I will add that even when using the same recipe consistently, I often vary the percentage increase in rise during bulk  - sometimes on purpose, or sometimes due to timing when I get out of bed.   I have yet to find any real conclusions, because, IMO ,  even if I get the bulk exactly right, it is so easily to have that undone by putting it in the oven before it has reached the optimal final proof stage, or worse, overproofing.  

albacore's picture

I can't claim credit for it - I read about it "somewhere" but I have used it on occasion, usually when I've had a sluggish bulk, and it does work.



Benito's picture

I’ve read that on IG as well, but I can’t imagine cutting off a chunk of my proofed dough at that point.

albacore's picture

I just use a small sharp knife, do the test and pop the chunk back!

texasbakerdad's picture

For me, knowing when to stop the bulk and shape and when to stop proofing has been probably the most difficult part of my breadmaking. A distant second has been learning techniques to build dough strength, followed by shaping techniques, sourdough maintenance, fermenting processes.... etc. etc. etc.

Lately I have been developing a theory in my head about when to end bulk. I'd like to know what you all think.

#1, there is a minimum required amount of bulk time. This minimum amount of time is equal to the amount of time necessary to develop enough strength to achieve the optimal rise in the baked dough. The end of bulk fermentation signals the end of mechanical dough strengthening (which culminates with preshape and shaping).

Judging #1 is the hardest thing to do.

#2, There is some time between #1 and when dough hits its maximum rise that is ideal for the type of bread you are baking. If you want to maximize the openness of your crumb, end your bulk at the end of #1. If you want more uniform and less open crumb, wait longer, I think the consensus is halfway through the total rise of the dough.

Because of #2, depending on your desired crumb structure, the same recipe formula might have an ideal bulk at 20% of the total rise time or 50% of the total rise time. But it is a range, bulk too early and you won't have enough strength, bulk too late and... I am not sure... way to late and your dough doesn't have enough time to recover from a rough shaping routine.

regarding judging #1, I agree with what Maurizio says in bullets 2, 3, 4, and 5. Also, I think there is a minimum amount of air needed in the dough before 2, 3, 4, and 5 are able to be achieved, in other words, attaining Maurizio's 2, 3, 4, and 5, require that an adequate amount of air in the dough be present.

clevins's picture

One of the things I like most about Maurizio's posts are the clear pictures at various stages. If anyone is wondering what he means by some of those bullet points head over to his site and look at some of the basic sourdough recipes to see the pics. 

albacore's picture

I think it's worth bearing in mind that often there isn't one single correct point for the end of bulk. For example, if we look at a typical 20% wholegrain, 75% hydration dough, then in terms of volume increase we could finish bulk at 20% or 60%.

What might be different is how we handle the dough next. The 20% one could have a 30 minute bench rest, stitch shaping and perhaps 60 minutes ambient proof before retarding.

The 60% one might have a reduced bench rest, if any, and a very gentle letter fold shaping with no ambient proof.

Both ways will produce good bread, but probably with different crumbs and maybe flavours.


mwilson's picture

It seems many have a hard time understanding bulk fermentation and particularly marking the point where enough is enough.

Can’t say I’ve ever been in this camp of dilemma. For me bulk fermentation is so very easy to understand.

Firstly, why do we bulk ferment? For flavour some might say - Sorry no, wrong answer.

While bulk fermentation can achieve a number of things, in essence it is about one thing and one alone, we all know it… “Strength”.

Now do not confuse this with gluten development, while related it is not the same thing. I will still bulk a fully developed dough! e.g., ciabatta, panettone – soft doughs.

Strength, strength to hold its shape. We bulk to allow gas trapped within the network to fill the dough; this gives it a "liveliness".

This gas exerts an internal pressure upon the glutinous network. In my own words I think of it as "tying up extensibility", consider the importance of that when applying stretch and folds.

Bulk fermentation can be judged upon how the dough rests after shaping. If it loses height it wasn't bulked enough, if it keeps its height the bulk was sufficient and if it gains height the dough was shaped beyond the bulk required. Although in all these cases they are subject to other factors and the bakers’ choice, but the point remains. To hold the shape.

Bannetons and moulds can allow for erring on an under bulk because they force the dough into the desired shape.

When dividing dough pieces they are commonly rounded and rested as a pre-shape stage, this of course is done to observe the strength of the dough.

How much does it spread? Does it lose any height?

This notion is expertly demonstrated by the late Maestro Alfonso Pepe in this video:

mwilson's picture

I would like to pay tribute to Maestro Alfonso Pepe who died earlier this year at the age of 54 after suffering a long illness. He received high accolades in a number of panettone competitions, including first. I know I will forever recognise his amazing talent.

JonJ's picture

...pointed out to me by texasbakerdad

Just from this comment I'm going to experiment with doing a pre-shape earlier than I normally would and making some notes about ability to hold shape at that time and the resultant final loaf.