HOME->SD->Detmold 3 Stage

The picture shows the testloaf of test # 1 - without dough fermentation. The top "explosion" is a slashing issue. I made too many slashes on top and the expanding dough took the way of the least resistance. Nevertheless, it demonstrates quite drastically the bacterial activity in a starter grown this way since practically no dough fermentation after mixing the dough took place.

Motivation

There were several reasons to go about this. The previous methods to grow a starter, in particular the last one, where I went by the growth phases were good but essentially driven by the starter's needs, i. e. when the starter reached a certain state, I would make bread. Originally, I figured that it would be possible to iterate to a procedure which would turn out to be superior but the matter turned out overly complex and with the means and time available impossible to implement. The Detmold 3-Stage process promised to give a high quality starter with defined, constant and repeatable paramenters. This speculation turned out well, the result is indeed stunning.

Another factor was that I had no firm control on the temperature parameter so far. Growing the starters with elevated temperatures with the sources I had available always had some fluctuations because it was not regulated. I tinkered for a while with a mechanism to control a proofing chamber like thing, but the water idea shelved that project.

Background

The multi stage sourdough growth procedures where an initial inoculation is refreshed in multiple steps to grow the amount for the final dough are common with natural sourdoughs. French, Italian, German, San Francisco, Russian, Finnish etc. sourdough breads are made in that manner. The variation of parameters, mainly temperature and hydration, is used to influence the taste and rising properties of the final dough. In particular, during the stages the amount and kind of organisms (yeasts, homo- heterofermentative lactobacillus bacteria) grown are influenced to obtain desired properties of the final products. To reliably rise rye based breads without baker's yeast, only the 3-Stage process is applicable.

One example of the classic 3 Stage sourdough process uses for stage 1: 2 - 4 hours with 100 % hydration at 80 F - 84 F (26 - 28 C), for stage 2: 5 - 12 hours with 70 % hydration at 76 F - 80 F (24 - 26 C), for stage 3: 2 - 3 hours with 100 % hydration at 84 - 90 F (28 - 32 C). Stage 1 is used to promote yeast and lactobacillus multiplication, stage 2 for developing acid and stage 3 to develop all microorganisms [1].

The folks at the German Federal Institute for Grain-, Potato- and Fat Research (Bundesanstalt fuer Getreide-, Kartoffel- und Fettforschung (BAGKF)) in Detmold/Germany have tweaked the classic 3 Stage sourdough process and came up with the Detmold 1, 2 and 3-Stage processes. These procedures include a much longer stage of 15 - 24 hours (with the 3-Stage, it is the 2. stage) than the standard 3-Stage sourdough process mentioned earlier and improve upon it [2]. The process has been developed empirically at the BAGKF. The exact parameters, ratios, weights and temperatures for desired dough or starter amounts can be seen at my Detmold 3-Stage Calculator.

Jeffrey Hamelman, in his very recommendable book: BREAD, A Baker's Book of Techniques and Recipes mentions this technique, a small section can be seen here.

Implementation

The main consideration in implementing this process was to manage the temperature paramenter over a relatively long period fairly accurate. So far, the means to warm my growing starters were computer monitor, oven light and heating lamp in large plastic containers. But, since all the heating sources were unregulated, they fluctuated with the surrounding room temperature which is several degrees colder during the night.

What I came up with was to use water as temperature controlled media with a regulated heating element and some kind of circulation to move the water around, so it has the same temperature everywhere and no heat or cold pockets develop.

I found that aquarium water heaters had a good temperature range of 68 - 93 F ( 20 - 33 C) for sourdough fermentation and could be expected to keep the temperature within 1 F as long as the surrounding room temperature is below the set temperature. I purchased an aquarium heater - eventually a 150 Watt unit. A 50 Watt model turned out to be too weak to change the temperatures within a comfortable time frame. To circulate the water, I used a small fountain pump which was in an unused room fountain. The left picture show the heater and pump. The right picture the unit (uncovered) in action with a small culture container fermenting in a 5 gal container. The container moves and spins with the water circulation. For temperature measuring, I use an older baking thermometer calibrated with ice water.

I also use the same setup to ferment dough in a larger container. This shows mixed/kneaded dough a 1500 g (3+ lbs) loaf in a basket in a larger bowl fermenting after punchdown in a 10 gal container.

	(fermentation setup about a year later)