REM picture of Lactobacillus sanfranciscensis. Source


This is my contribution to the Art of Breadmaking project. You can learn more about it HERE

In this livejournal entry I am documenting my experience with the recipe of developing a sourdough starter with lactobacteria san-francisco in 2 days.

The premises for the method

1) Lb sf needs precursors in the dough in order to kick in, to start growing in large numbers. These precursors are lactic bacteria lb pontis, lb plantarum, and lb fermentum. They outcompete other microorgainsms in rye and wheat dough at temperatures above 35C - 37C . So, step one is to create conditions in dough slurry for these do develop.

2) Lb sf grows best at 5-20% inoculation and at  32C (no higher than 32C and no lower than 20C), so the second step in starter development is to feed the culture with fresh dough and maintain it at 32C for the LB SF to grow in large numbers and outcompete other microorganisms in the culture, for Lb sf to become dominant.

3) Wild yeast  grows best at 28C, and high extraction flours are the best sources of wild yeast cells and spores. So the third and the following feedings should be with whole grain rye or whole grain wheat flour and fermentation kept at around 28C to encourage yeast growth.

The suggested maintenance schedule for the starter is to inoculate regularly at 5-20% level, keep culture whole grain based, around 28C. However, Lb SF will remain dominant even at 40% inoculation of wheat doughs, in 25-30C temperature range. So, it is safe to feed your starter in 5-40% inoculation range: 1 part of flour in ripe starter to 2.5-20 parts of flour in fresh dough, kept at 25-30C, preferably in 50-75% hydration range. To increase acidity , oxygenate your starter, preferments, and sourdough regularly - knead it from time to time.

RECIPE
STEP ONE
20g whole rye flour
240g water, 25C
mix, pour into a ziploc bag, close, submerge in warm water. Leave for 18-24h @ 35-40C, ideally at 37C.

STEP TWO
add
100g whole grain wheat flour, or whole grain rye flour (wheat flour is preferable). Close and submerge in warm water. Leave for 18-24H at 30-35C, ideally, 32C.

STEP THREE
take 30g of that soupy mixture, add
100g whole grain wheat flour
45g water
knead until homogeneous, leave for 24 h at 20-30C, preferably at 28C in a closed glass or plastic conteiner.

STEP FOUR and all following
feed the starter once daily in the following manner
4-5g ripe starter
50 g whole grain wheat flour
33g water
knead, leave in an enclosed glass or plastic contener at 20-30C for 24h. To increase acidity, oxygenate regularly: knead it from time to time during fermentation or tear into pieces.

Illustrations

1) mise en place: heating pad from a pharmacy on the lowest heating setting gives about 40C which is ideal for this method.



This method starts with whole grain rye flour, which sometimes FAILS to ferment for unknown reason. To increase chances for success I took 10g of whole grain organic rye flour and 10g of rye flakes, to provide TWO different sources of Lb plantarum, Lb fermentum and Lb pontis in the first mixture.

rye flakes


The first mix of rye with water in a ziploc bag



It sits in warm water on top of heating pad set onto lowest setting, T= 37C

I covered it with linen to create thermos effect, to protect from cold room T in my kitchen at night.


NINE hours later the temperature stayed stable at 37C and the mixture became foamy


20 hrs after the set up I opened the bag to feed the mixture. The stench was almost unbearable - smelled like vomit and rotten corpses in there. So, for those who wonder if this method skips the stinking phase, - NO it doesn't, It makes it worse, LOL. However, it doesn't matter. Along with stinky microbes (in small numbers) we had grown large numbers of good lactic bacteria in that mix.

2) I added to the bag 100g of whole wheat. Again to make sure I had TWO different sources of desirable microorganisms, I used organic whole grain wheat flour and wheat flakes.


To keep this mixture at 32C on a heating pad, it is sufficient to place a soup plate between the heating pad and the warm water vessel in which our starter is fementing

This mixture will also become foamy in a few hours

Eventually, the foaming stops, foam dissolves in water, smell changes from pure vomit to acidic vomit, tastes extremely acidic, vinegary. Mixture after 18h at 32C, ready for the next feeding, the next stage in starter development - yeast propagation at 28C.


pH of this mix is in the range of 4.0-4.2



3) I took 45g water, added 30 g of slurry from the bag, dissolved it all, added whole wheat flour with some cracked wheat and cracked rye grain in it and left it to ferment at 28C for 24hrs. On top of my fridge is a constant T of 28-30C, day and night, any season.


24 hrs later it rose in volume from 150ml to 250ml


Another sample was fed with purely whole wheat flour, it also got going some yeast fermentation in it



I gave it full 36hrs, it was very stiff



I didn't discard the remaining slurry in the  ziploc bag, but fed it bread flour every 8-12 hrs, 1:1 ratio, 150 % hydration, and got another beautiful starter going in 48hrs. Maybe it's a proof that to develop yeast in that starter you don't really need to feed it whole grain flour, after all. But  then it does require a higher number of feedings/ more flour, to get it going.

4) Next I switched to maintenance and testing of the starter. I have fed with 1:20 feeding , stiff form, let ferment for 24 hrs at 28C

whole rye form of starter



this is how whole wheat form of starte it looks at the end of 24h fermentation at 28-30C

during the first hours after feeding it goes through a phase of strong lactic fragrance (like yogurt or kefir), then as it becomes more ripe it smells 'like sourdough', much more complex and bread-like fragrance.

TESTS
I tested the starter for its leavening power. It's supposed to lift white wheat dough with bread consistency or softer (like chiabatta), at least 4-4.5 times in volume in 4-8 hrs of fermentation at 25-27C.

It passed the tests
260g (250ml) of wheat dough inoculated with 10% starter, 90% hydration


6 hrs later at room temperature





I also tested this starter in breadmaking. I baked white bread, 50% rye bread (50% flour is 85% extraction rye, and 50%
 flour is 85% extraction wheat ), and 100% whole rye bread.

White bread was pronounced acidic, not like true san-francisco style, but more than french sourdough
Sponge 10% inoculation, 6hrs at 25C
Dough 70% hydration, 2% salt, 30% flour comes from sponge, improved mixing method, 1hr bulk fermentation at 27C, 15 min bench rest, 2.5hrs proof at 32C. 1 hr bake at 350F.




50% medium rye was perfecition. The best ever. Just the righ acidity and full bodied fragrance.



100% whole rye was not acidic enough (to my taste) but it was the most fragrant rye bread I have ever had honors to sniff. The best. Even as its sponge and then dough were fermenting the fragrance was otherworldly, heavenly. I personally like sharper acidity in black rye. No to the point of being vinegary, but still, more pronounced. I will try oxygenation technique on its sponge and dough next time to see if it helps.


Canadian Pioneer bread, 100 % whole rye with sunflower seeds.