The Fresh Loaf

News & Information for Amateur Bakers and Artisan Bread Enthusiasts

Commercial Yeast - Retardation - Flavor

DanAyo's picture
DanAyo

Commercial Yeast - Retardation - Flavor

Most of my breads are made with sourdough. When this type of dough is retarded the flavor profile changes noticeably in relationship to the length of cold fermentation.

It seems commonly accepted among most bakers that a commercially yeasted dough will also reap a flavor benefit from retardation. I have believed this from my earliest years of baking. Both breads and pizza doughs are said to benefit in flavor from varying lengths of cold fermentation.

Recently a comment posted by Doc challenged my previous thinking. He claimed that retardation of commercially yeasted dough had no affect on the flavor of the bread. This statement was shocking. In an attempt to learn the truth a call was placed to Lesaffre (makers of SAF yeast) and a seemingly experienced baker told me that bread flavor was enhanced in proportion to the amount of time it fermented at cold temps. He laid my concern to rest (for a while).

4 days ago a batch of Bouabsa Baguettes which use Commercial Yeast were mixed with enough dough to bake 3 baguettes. The bake is posted HERE. The first baguette retarded 24 hr, the second - 48, and the last 72 hr. To my surprise all 3 loaves tasted extremely similar with little (maybe none) change in complexity of taste.

Has anyone else tried a similar test?
If so, what were your findings?

I appreciate your input,
Danny

idaveindy's picture
idaveindy

Yeah, craft pizza makers swear by cold ferment.

Three variables:

1.  The length of time of any room temp head start given to the dough in order to get the yeast going. The exponential growth behavior of yeast means a head start up front makes a large delta later on.

2. Whether or not the refrigerator is above or below the magic temperature, which I seem to remember you once mentioned as being around 4 C.  @3.5 C and below, little to no activity. @4.5 C and up, stuff happens.

I can imagine the same dough/yeast  behaving differently depending on whether those two conditions were met, or not, or one or the other. (4 combinations.)

3. Dough temp at beginning of room temp ferment period and when put in refrigerator.

idaveindy's picture
idaveindy

Hamelman, in Bread, Appendix, page 364 (1st ed.), "Amylase Activity and the Question of Malt," third column, indicates that yeast and the sugar-making amylase enzymes are still active during retardation.

alfanso's picture
alfanso

did you sample each one as freshly baked or awaited until all three had been baked?  I'd hope the first.  But even so, isn't it possible that in tasting each a day apart, you really couldn't discern any flavor difference due to the lack of side by side comparison.  And if you did wait, then the first batch would have been 48 hours old before sampling.

As with levain bakes, there is a point where the longer retard no longer enhances flavor, the maximum flavor has already been coaxed out.  In levain doughs, at some point, the protease action would begin breaking down the dough.  In CY doughs that may not be the case, but once the sugars have been consumed and the dough matured, there is no place for the dough to develop any further. 

Worthy of consideration?

DanAyo's picture
DanAyo

I taste tested both ways. 

  1. After baked and cooled down
  2. compared from fresh frozen

There may have been a slight change in flavor (maybe not), but I would have expected it to be much more noticeable.

I hope others give this test a try.

DanAyo's picture
DanAyo

Alan, this may provide a better flavor test.

Mix a single baguette using the same formula and method for 3 consecutive days, 24 hours apart. Retard all doughs, with the final loaf retarding for 24 hr. Bake all 3 at the same time, then test for flavor after they have cooled.

Anybody have improvement suggestions for this test?

phaz's picture
phaz

I believe the problem is the cold. I'd try a room temp "ferment" ie leave at room temp till something like 4x expansion. Knead, then proof to something like 2x or 3x growth. With temps in the 60s, that's about 16 hrs from mix to bake ie fermentation time. I always found a different flavor when I oops and fall asleep after mixing a dough. I do most all my beads this way now. Enjoy!

Benito's picture
Benito

Hi Danny I posted in the CB but didn’t see your post here too.  About 2 years ago I started baking bread starting with CY.  I purchased Peter Reinhart’s Artisan Breads Everyday.  In that book he convinced me that by cold retarding the dough, it will develop flavour.  That is in reference to CY breads. So not know any better I went along with it and used his methods and everything seemed fine and dandy.

Then I started down the sourdough path and also found the treasure trove of information and great bakers.  In the following year I have learned a bit about the microbiology of sourdough, not tons but just a bit.  My pH tests have also taught me some as well.  It quite apparent that at fridge temperatures as low at 2ºC in my fridge that the microbes are metabolically active.  I don’t have any of the Petrie dishes or other lab equipment to examine he microbes, but my pH meter does show reliably that the pH of the dough slowly drops during refrigeration at 2ºC a temperature where the LAB and the yeast aren’t actively reproducing.  So although not reproducing they are still metabolizing and creating things that will impact the flavour of our sourdough breads given a cold retard.

I should the next time I make a CY baguette, it I didn’t occur to me to try this, take the pH of the dough at the start of bulk fermentation and the end, then the pH was final shaping to show it if changes over time.  I have no idea if CY make any acid, apparently the wild yeast contribute to acid production.

DanAyo's picture
DanAyo

Benny, I am under the impression that CY does not produce acids, but the yeast itself is able to produce flavor.

Maybe someone else has a more definitive answer.

Benito's picture
Benito

I’ve been told by Mini Oven that the yeast will contribute some acid as well, at least the yeast in our levain’s.

Now CY will produce during fermentationyeast produce a whole range of flavoring compounds, including esters, phenols, and a large variety of other chemicals.  I wonder at what temperature does the metabolism of these compounds stop?  What is the minimum temperature we can cold retard CY breads that allows them to continue to produce these compounds positively improving flavour?

idaveindy's picture
idaveindy

mwilson posted a cool diagram of yeast metabolism last year. It shows a lot of outputs: http://www.thefreshloaf.com/node/61674/back-uni-first-lecture

 

Benito's picture
Benito

Thanks for pointing that out to me Dave, I don’t recall seeing that post before.  Again, I wonder at what temperature do CY stop being metabolically active and stop mailing those compounds?

idaveindy's picture
idaveindy

I just saw your comment on the old thread. and just  before that, I sent michael a PM inviting him to this thread.

Since we are talking about a difference of 48 hours, 3 days vs 1 day, my theory is that small differences in temp have a cumulative effect.  You are at 2 C, I am at 4.4 C, someone else at 3.5 C, someone at 5 C.  After 72 hours, different doughs at different temps will have diverged.

Then add in possibly different starting dough temp, and length of ambient ferment time prior to going in the fridge, and you end up with doughs having a different "head start" on each other.

So... yeah..... sometimes a better flavor profile could develop, but under ever so slightly different curcumstances, it might not.

--

I can't set my fridge to under 4.4 C (40 F I think) without freezing the food that sits directly in the airflow.

I think refrigerators are as idiosyncratic as ovens.  

yozzause's picture
yozzause

In the old days when refrigeration  was just not available for retardation and many bakeries were just one man shows and the bakers had to juggle and master longer and slower bulk fermentation times to fit in with their schedules. Often this was achieved solely with the amount of yeast used in the mix. I do remember traveling to a small country town of Wyalcatchem in Western Australia to visit a country apprentice that had  been visiting us at city bakery for  the experience. It was enlightening as we did the dough making , lit a small fire in the wood fired oven before a quick beer at the pub and  home to bed for a sleep  returning some four or five  hours later to process and bake. I quickly learned that these bakers  were jugglers and in tune with what was going on around them reading the weather and how it was going to effect the dough, especially in hot spells, yeast was reduced  and sometimes extra salt was added too. These slow doughs did produce breads with much more flavour!      Toward the end of my commercial baking career i worked as the dough maker for a bakery that was owned by a multi national  and the most popular loaf of bread was a wholemeal loaf that was still produced via a 2 arm stirling mixer with a capacity for 600lbs of flour mixing time was 20 minutes and bulk proved for 4 hours. i kick myself now that i didnt take any photos of the way things were done. So Dan  another angle for your exploration  yeast quantities and BF duration on flavour.                                                                                                                       I just blew the dust of my technical college notes that are 53 years old and there is a guide to yeast quantities and fermentation times  these are given in LBS TO THE BAG before we went over to decimal weight.

dough time    yeast lbs per (bag flour150Lbs)

8                      1

7                       1&1/4

6                       1&1/2

5                       1& 3/4

4                        2

3                        3

2                        4 

1                        8

 a calculator will help to  give a more modern version  and even conversion to grams too 

kind regards Derek