The New Wild Yeast

I arrived back home from the yacht delivery a week or so ago, to find to my dismay that the home reserve of the precious wild yeast we used on the boat had been chucked down the drain in a spree of spring cleaning.
Fiddlesticks!
So I started again. This time I used some crushed rye that I bought some time ago. I put it through the coffee grinder to get it into smaller pieces, then added half a cup of rye flour and enough water to make a batter. I reasoned that there should be at least some yeast on the whole grains to be harnessed in my endeavours.
And I was right. The mix started to ferment within 24 hours. By 36 hours there was a nice froth on top. I then washed the yeast to get rid of some of the lactic acid and fed it some wheat flour.
For those not in the know, you wash the sourdough by adding a lot of water and thus diluting the sourdough. This will dilute the lactic acid, but not hamper the yeast itself. Then you chuck away about three quarters of the thin mix, which will get rid of the same percentage of the lactic acid. Now you feed the thin mix again with flour, not adding much water. This will leave you with a sourdough containing less lactic acid to hamper the growth of the yeast. This procedure I got from the book Classic Sourdoughs Revised by Jane Wood and Ed Wood. I have a Kindle version, available from Amazon.com.
It is a good idea to wash a yeast after thawing, especially one that have been sitting in the refrigerator for a long time. Some of the yeast die in the colder environment, so you get rid of some of that as well. And you end up with a revitalised yeast.
After this washing treatment, my lot developed a brown fluid on top within 24 hours, so I stirred it all back in, then washed it again. This time fed it rye flour. After another 24 hours the sourdough was bubbling away happily and developing a nice sour smell. Then it was time for the next step, the first loaf.
I made the starter using a cup of rye flour, half a cup of the sourdough and some lukewarm water, enough to make a thick batter. This was left to develop for about eight hours. The dough was completed by adding a pinch of salt, a cup each of white bread and brown bread flour and some lukewarm water, just enough to make the dough knead-able.
I kneaded and folded the dough for about twenty minutes. During this time the dough absorbed about another half cup of the white bread flour that I used to flour the kneading board. I wet my hands with some cooking oil and patted this onto the dough ball, sealing it against drying out. Left overnight in the plastic mixing bowl with a lid on, in an ambient temperature of around 20ºC/68ºF, this dough almost tripled in volume.
I kneaded this down to the original volume and patted it into a small loaf shape. I decided on a rustic loaf, as this was still an experimental yeast. Fancy loaves or flat breads will come later.
The loaf was left to rest on the baking plate for another two hours. During this time it again almost doubled in volume. The experiment was clearly working and I have a very virile yeast. The loaf was baked at 200ºC/400ºF. I started with a cold oven and let the loaf heat up with the oven. I like to think this gives some additional oven spring. After fifteen minutes I brushed some water onto the top of the loaf to facilitate crust forming. I shall make some more experiments later with getting steam into the oven, but this has to do for now. The loaf was baked for forty minutes, after which the oven was switched off and left to cool for another twenty minutes.
The result was a magnificent loaf with nice large bubbles inside and a good soft crumb. The crust was a bit chewy too. And the bread had the characteristic sourness expected from a wild yeast.
Chalk up another successful yeast capturing experiment. Now the fun starts!

This blog also linked to Yeastspotting! 

Authored by Johan Zietsman
Last updated on 2012-12-12