ars pistorica's blog

Submitted by Juergen Krauss on January 17, 2013 - 12:31am.A longer reply will follow in due time

I think the major difficulty is to separate the "time percieved by the observer" from the "physical time elapsed in the system under consideration". Common language has no real way of dealing with this. (In order to understand what "observing" means it is useful to look at some of the works of Einstein, Bohr, Heisenberg etc. ) My view in brief: If I set a kitchen timer I switch my perception of time over to the ticks on the face of that timer, and give away all my powers. If I watch the dough I switch my perception to a "clock" associated with the fermentation process. This "clock" has as ticks on its face things like acidity, smell, taste, viscosity,... (you name it). I can then intervene when I deem it fit to suit my tastes and expectations.

Submitted by ars pistorica on January 17, 2013 - 11:31am.

I did this years ago.  It is also, in part, one of the reasons why I believe the mass effect occurs.

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“Co-fermentations enable micro-organisms to use substrates that are otherwise non-fermentable, and increases the microbial adaptability to difficult ecosystems.  Under the influence of several ecological factors the homo- and heterofermentative LAB have a great aptitude for producing metabolites other than lactic acid and for co-fermentations which lead to an increase in energy yield.”

Gobbetti, M. and Corsetti, A.  “Lactobacillus sanfrancisco a key sourdough lactic acid bacterium:  a review,” Food Microbiology, 1997.

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“It was shown that peptides were able to improve growth of  L. sanfranciscensis on medium limited in amino nitrogen. Based on additional information it was concluded that lactobacilli prefer the uptake of peptides which are subsequently hydrolyzed in the cytosol.”

“Further investigations were performed on the influences of lactobacilli and endogenous wheat enzymes on wheat proteins. The results indicate that sourdough fermentation has a major impact on gluten quality. Depolymerization and hydrolyzation were observed and could be attributed mainly to low pH cereal proteases. During fermentation the pH is lowered from about 6.2 to 3.6 by microbial metabolism and this leads to an improved proteolytic breakdown. Additionally we suppose that peptides generated by cereal enzymes are subsequently taken up by lactic acid bacteria to meet their amino nitrogen demand.”

Thiele, Claudia.  “Hydrolysis of gluten and the formation of flavor precursors during sourdough fermentation,” 2003.

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Mass effect explained.

It's just a bunch of bio-feedback loops, each starting and ending at different times, all depending upon and affecting the other, and all with a tendency toward an increased energy state.   The more of them there are, the more contact points that can be made, the more accelerative the whole process becomes.

This is what happens when evolution gives a species so much metabolic choice.

Bulk fermentation is done when a dough is strong enough to remember its shape after baking.

A fellow user asked a great question recently:  How does a baker tell when bulk-fermentation is finished?

Of course, I do not think we can begin to answer this question without firstly asking some other questions, like:  What is fermentation, and how does one measure it?  And why ferment in bulk in the first place?

My favourite question to ask baking classes or new baking apprentices is, what is bread?

The simplest answer I've found is that it's a paste made from the ground-up seeds or grains of tall-grasses combined with water.  Sometimes there's salt, sometimes not.  Sometimes it's leavened, sometimes not.  Sometimes it's baked, sometimes not.

For the purposes of this discussion, I think it's best to focus on one grass, wheat, as well focus on only two types of controlled fermentation, alcoholic- and lactic-acid-based.

We know that fermentation is a series of irreversible, physical changes that take place once the conditions for fermentation are met (in our case, mixing flour, water and the leavening agent).  The aim of these fermentations?  To make whatever it is we are fermenting edible (nutritious and tasty); of course, there are many other uses for fermentation (like preservation), but these are outside the bounds of this discussion.

We also know that time is completely irrelevant to fermentation.  What does matter, especially for flavour, is the type and number of physical changes that take place in the fermentative process.  We also know the elements that most affect the type and quantity of aromatic flavour compounds in a final dough come down to substrate type and condition, redox potential, inoculation percentage, the nature and condition of the sourdough culture, and the nature and conditions of the fermentation.

So, I ask this question to anybody reading, why do we ferment in bulk?  Once we answer this question, we must then answer the second one, how do we measure fermentation?  And what, exactly, is "done?"

I am a Jim Lahey disciple, philosophically speaking.  There are not many in the professional-baking community.

I will forever remember the coffee-bean-like smell of torrefied wheat bran emanating from the original Sullivan St while walking past on my way home at 3 a.m.

Here is a sourdough adaptation of the no-knead recipe in his book, but this version is truer to the Pugliese dough at his bakery.  Please note, the yield has been adjusted to be the same as in the book, as well as the overall hydration and salt content.  Additionally, Lahey uses yeast at the bakery to achieve a roughtly 4.5-hour total fermentation-time, and, if one wishes to more mimic that dough, a scant 1/8th-teaspoon (equal to .13% of mix-flour weight) of instant-dried yeast may be added to the dough.  This will approximately decrease overall fermentation time by one-third.

Starter for Lahey-Style Sourdough

6.25 g mature starter, 60% hydration

30 g water, moderately cold (15°C)

25 g flour, all-purpose

25 g flour, whole wheat

1.  Mix ingredients together using your hands until a homogenous dough is achieved, about 2 mins.

2.  Let ferment at room temperature for 10 - 14 hours.

No-Knead Lahey-Style Sourdough

356.5 g flour, all-purpose

70.5 g starter, from above

274 g water, moderately cold (15°C)

8 g salt

1.  Place flour in a large, non-reactive mixing bowl.

2.  In the bowl of a blender, combine the water, starter and salt.  Blitz on highest speed for 30 - 45 seconds, until no large particles remain.

3.  Pour the blender contends into the flour bowl, using a spatula to scrape out every last bit.  Stir, using only one hand, until a shaggy dough is achieved, and every particle of flour is hydrated.  Cover with a plastic bag, and let ferment for 4 - 5 hours at room temperature.

4.  Lightly dust a large, flat work surface with flour.  Using a dough scraper, gently remove the dough from the bowl.  Using lightly-floured hands, grasp dough from the under-side and gently coax into a flat, even square, taking care to not de-gas dough too much.  Fold the dough's edges into the center to form a round.

5.  Gently place round seam-side down into a deep bowl lined with a cotton tea-towel that has been generously dusted with flour.  Amply dust top of loaf with a 50-50 mixture of flour and days-old breadcrumbs that have been ground up finely together and sieved.  Gently fold the towel's edges over the loaf, and let proof for 3 - 3.5 hours at ambient temperature.

6.  One hour into the proof, preheat oven to 260°C and a 4.5 - 5.5-quart heavy pot  for two hours.

7.  Proceed as per the normal recipe, with two exceptions:  firstly, the bottom of the loaf (that is, the seam side at the bottom of the bowl) is inverted to become the top of the loaf, and the loaf is not scored; second, bake at 260°C for 40 minutes with the lid on, and 250°C for another 16 to 20 minutes with the lid off.

City loaf

100% flour, stone-ground wheat, 80% extraction rate

89.9% water

24% starter

2.76% salt

Percentage of flour pre-fermented.  15%.

Final dough temperature.  23.5°C.

Autolyse.  2h.

Bulk ferment.  4h30m - 5h.

Divide & rest.  20m - 30m.

Proof.  12h - 18h, at 8°C.

Bake.  265°C, with steam, for 5m, and then 250°C for 35m.  Vent, 235°C for 10 - 20m more.

Starter, city loaf

100% flour, stone-ground whole wheat

60% water

16% starter, bakery

Final dough temperature.  23.5°C.

Fermentation time.  10 - 12h.

Starter, bakery

100% flour, stone-ground whole wheat

60% water

10% starter, bakery, 24h-old

Final dough temperature.  23.5°C.

Fermentation time.  24h.

City loaf.

Timing is everything.

Good timing makes a joke work, as bad timing does the same for tragedy.

For bread, though, it means nothing.  Bakers who brag about using long fermentation times puzzle me.  I mean, I know what they mean, but do they?  I, too, am guilty of using this idea when discussing bread.  Why?  It's convenient.  Everybody knows it.  It's an available reference point.

And yet it all means nothing.

Handmade things that take a long time to make are usually thought of as being of a higher quality than a similar product made fast and cheaply on an industrial scale.  Why?  The answer to this question will help us a bit further on.

First, let's talk about time.  What is it?  For our purposes, it's the same thing as dough rheology, the progression from one physical state of being into another, with the possibility of never returning to the previous state.  The tricky thing to pin down, though, is the rate of change, which is consequently affected by the hows and whys of the physical transformation attempting to be measured.

For us, as bakers, time is merely a very long string connecting together a series of snapshots of a dough's state of being.  And, no, I am not about to get Heideggerian.  For me, this offers a better framework by which to understand time.

Some bakers view time as an ingredient.  This is silly.  It is okay to have one cup of thyme, but not one cup of time.  Others, still, insist it is a procedural parameter, which it certainly is.  In a real-world environment, we all have busy lives.  There are only so many hours in the day, and this might dictate our baking schedule.  It is much easier to control time when it is viewed as an outcome, and not as an independent variable.

Fermentation is the change in the physical state of being from a dough and into bread.  There are simply so many controllable variables available to a diligent baker that she might be able to make two loaves of bread, both with nearly identical results, but with vastly different times it took to achieve that end result.  This tells us that time is irrelevant to understanding fermentation.

So, how to we better measure the physical state of our would-be bread?  What tools are available to us to better understand and measure the rate of metabolic activity, the degradation of the dough?  There are many methods already available to the baker (e.g., measuring pH, CO2 production, and so on).  What other data points can we find to build a better, more robust model?

And why does taking a long time by hand necessarily make something better?  Because:  there's simply more time to interact with the substance to be measured, and thus more available data points for an astute baker to collect (with or without her consciously knowing).  Good bread is not about time; it's about doing the right thing at the right time.  It is in our, the baker's, interaction, when and how we handle the dough, from which good bread emerges.

So, let's take our time and find more reference points.  Answer why and we discover how and when.

Thought Experiment #2:  What is the difference between a starter and a bread dough?

One question I like to ask new apprentices is, what's the difference between a starter and a bread dough?  Or, for that matter, between a pre-ferment and a bread dough?

I have never received a satisfactory answer, and I think because there isn't one.  Not an answer, a difference.

Except one:  without salt and without structure it won't be very tasty when baked.

We add salt to bread for taste, structure, and its effect on fermentation.  We give structure to bread so we can develop flavour as well as bake it into a functional and desirable shape.

Pre-ferments -- which is, all things being equal, yeast-based fermentation at optimal conditions -- allow commercial yeast to display the flavour of the grain beautifully.  Their flavour is undeniably better than direct-method doughs.

I return to my original question, but rephrased:  How can we make a pre-ferment a dough?  That is, what is the maximum time we can delay the addition of salt as well as not developing structure without impacting the flour-water conditions necessary for structure (that is dough-shaping and baking purposes)?

The answer's not terribly complicated.  Let's work backwards, shall we?

We know from the recipe resurgence of no-knead (Lahey & Co.) and unknead (Macguire, Hamelman, other Calvel disciples) that, given a longish bulk-fermentation and relatively wet dough, we can handle a dough more, both in terms of how often and how vigorously, during the first half of the bulk fermentation without there being too disastrous a loaf turning out in the end.

But, the loaf will be weak, so it will need to be baked in conditions with plenty of retained heat.  A hearth-style bread will be best.  Being on the weaker end of the spectrum also means giving it a shorter proofing-time.  This limits the shapes that can be used for best outcome, such as a round or a baguette.  The bulk time also cannot be too long, either, or else the dough will not be strong enough to shape and bake.  Too short a bulk time and there's no flavour.  So, we'll choose 3 hours as our time, the sort of minimum floor-time most bakers recognise as necessary for good bread.

Pre-ferments, especially poolish, bring significant protease activity, which helps texture, extensibility and flavour.  A great poolish needs 12 hours; we have chosen 3, so the addition of an autolyse step, albeit brief so as not to undermine what we know will be an already weakened dough, will help.

So, let's start with a formula:

100% flour, wheat, 10% - 11% protein content

70% water

2.2% salt

.4% yeast, instant-dried

 A pre-ferment is made as a smaller amount separate from the rest of the dough.  For our purposes, let's do a pre-ferment-sized dough, a sort of "one-off" portion that really allows you to see there isn't a difference between the two.  Let's scale the formula to the size of 1 baguette.

Let's make the process as simple as possible, too:  it will take place in one bowl.  The details here, as all those on this blog, are for a standard home oven.  Mine is nothing special.

Here is the recipe:

215 g flour, all-purpose, 10% - 11.5% protein content

150.5 g water

4.7 g salt

.86 g yeast, instant dried

1.  In a medium-sized bowl, combine the flour and water just until a shaggy dough is achieved, and every particle of flour is hydrated.  The final dough temperature should be 23.5 - 25ºC.  Cover and rest en autolysis for 30m at ambient temperature, 23.5 - 25ºC.

2.  Sprinkle yeast evenly over dough.  Cut into dough using sausage-cutting technique.  Do not over-handle dough.  Your only goal is to evenly distribute the yeast.  Cover and allow to ferment at 23.5 - 25ºC for 1h 30m.

3.  Add salt, as above.  Once completely dissolved into dough, fold the dough onto itself, giving the bowl a 20º-turn after each fold.  Alternatively, the slap-and-fold technique can be used, but with only 1 or 2 necessary.  Cover and allow to ferment at 23.5 - 25ºC for another 1h 30m - 2h.  Give one set of folds, if necessary, during the first 30m.

4.  At the end of bulk fermentation, remove from the bowl and pre-shape for a baguette.  Allow to rest, 15 - 20m.

5.  Shape and proof en parisien for 45m.

6.  Bake, with steam, at 250ºC for 22m.  Vent steam, lower the oven to 235ºC, and bake for 5 - 8m more.

The result?  The best 4h30m baguette you'll ever make.  All the benefits of a pre-ferment but in direct-method.

Let's think outside the bread-box.

Thought Experiment #1:  Data Points

One of the basic questions bakers must ask themselves is what makes good bread.  Once we have quantified that, we can then elaborate the process and materials needed to reach those quantities.  Of course, each of us will have different ideas of what constitutes good bread, but that's really irrelevant to the this thought experiment.  What is exciting is the idea that we can quantify what is good bread.  If that's possible, then we can plot differences in taste, begin to explain with more clarity what it means when we like something.

Let's take a direct-method dough, for example, even the standard French dough:

100% flour

67% water

2% salt

.4% idy

Every home-baker reading this sentence also likely has Google.  Just from this formula, we can gather reliable data that might act as reference points for good bread.  Remember, though, in defining good bread you are also defining what is bad bread.

A good, reliable metric available here is the yeast.  There's a wealthy of information available via Google to be found.  What's more, we can also build our own data point.  We know the starting percentage of yeast, we also know the starting weight.  If we know its weight, we can reverse-engineer its make-up.  We can ask ourselves relevant data can we gather that might help us measure good bread?

Yeast is the major contributor of flavour compounds in this formula.  Instant-dried yeast do not produce that many volatiles.  These are knowns or givens.  They can easily be looked up.  We can also find the type of yeast, what it was selected for, its population per gram, the water content, the proportion of live cells versus dead cells, generation time, CO2 output versus temperature, volatile output versus temperature and/or food source, and so on.

We can also calculate the end population of the yeast with this data.  It is very easy to model.  The final quantities, in mg, of volatile aromatic compounds are also expressible.

How is any of this a data point?  Well, is the bread the formula produces tasty?  Why or why not?  What if we increase the yeast amount, and therefore the total final population and total aromatic compounds produced?  (Of course, we know that there is a fixed number the yeast population can reach based upon substrate conditions, but we can easily look this up and predict this, too.  Most formulas do not have the entire yeast population reach the death stage until several minutes into the oven.) What is the upper-limit of total yeast present before going into the oven that is desirable?

With these sorts of data points the baker can begin to build his or own model by which to gauge other formulas, revise their own, and so on.

Parameter-based Thinking

What is the difference between a car mechanic and an automobile engineer?  Right off the bat we know the second job title sounds fancier.  Why?  We assume you have to be “smart” be the latter.  “Smart” really just means educated, in this sense.  Doesn’t a mechanic have to know about cars, too?  Of course!

A mechanic must know her parts, the way they fit together and the way the unit works as a whole.  But why is an engineer paid more, considered to be the more prestigious job?  Because the job requirements of the engineer necessitate a greater level of knowledge.  He must know everything the mechanic does plus a whole lot more.

“Level” is the right word, because the class of information the engineer must know is categorically different than a repairman’s.

To follow this analogy further, why do cars only come in certain shapes, and why those shapes?  We could begin to ask this question of every functional design choice of the car.  The answer to most of the questions would be a “because” followed by an explanation based on a pragmatic understanding of why a car must be that way, because of its conditions of use, the type of people using it, and, really, there are only a limited-number of real-world physical solutions that work.

Bread, then, is no different.  It is a system, and it is vital to understand its materials and the methods by which it is put together.  Stopping here would make anybody a good baker.  Being a great baker, though, involves knowing the system’s limitations.

Here’s a real-world example.  While writing the Mozza book Nancy Silverton had trouble adapting the restaurant’s pizza dough to a home oven.  So, she changed the dough.  What conclusion can we draw from this?  That even Nancy Silverton had trouble being Nancy Silverton, at home.  Why?  The parameters were different.  A home kitchen cannot compare to an industrial-sized bakery that delivers dough to her restaurant.  By starting backward and listing known limitations  and the ways in which they limit us (a home oven, which means less overall thermal energy and also decreased ability to store or radiate the energy) one instantly realises only certain outcomes are possible (a much longer bake with less oven-spring and overall browning).

A better way of saying this is, use what’s around you.  This truism dates back to time immemorial.  I make a bad-ass pizza but I do not make a bad-ass pizza at home.  Or at anybody’s home, really.

Finding, listing and then accounting for all parameters is the hardest part of the challenge.  Part of this blog will be to begin a record of those parameters, as well as interpretations.  Collaboration is always welcome.