Yeast starters and starter cultures that contain yeast – like the original koji for which the Chinese Kanji (麹) was created – sometimes also contain other types of bacteria, fungus and even other yeasts.
Take, for example, sourdough starter. It’s easy to turn that into vinegar because there are already some bacteria and yeasts in there just like there are in kombucha.
Eventually, often with the help of wild yeasts and bacteria, both of these will eventually become alcohol. Vinegar is made from alcohol, either fermented fruits like apples or peaches, or from grains.
But controlling how much yeast, and especially what kinds of yeast get into a specific starter is how most alcoholic and non-alcoholic fermentations are successfully made.
It’s essential that any utensils and containers you use are very clean. Always kill off as many wild strains that may be lurking before starting or proceeding – unless these are part of your fermenting culture.
Sometimes rinsing everything with boiling water is enough. Other times it is woefully inadequate. Equally important is making sure ever ingredient is properly prepared.
Soaking tree nuts or beans, for example, helps to remove undesirable substances that can ruin fermentations, or mess up your digestive system.
Some yeasts work remarkably well at protecting crops from diseases. These are benign and helpful yeasts. But even then sometimes these microbes in large amounts actually cause allergies, and what are sometimes mistaken as intolerance to a specific grain or nuts.
So soak your nuts, seeds, grains, and legumes. Some recipes call for salt, vinegar, alcohol or lactic acid to help the process along, but it’s usually about how much salt is involved and how the water or moisture content of ingredients is affected.
Some yeasts can take can take up to a 7% sodium content, so controlling the entire microbiome of the things that you are making is crucial. Some harmful microbes can be eliminated by pre-drying or curing.
Soaking ingredients, along with treatment with enzymes produced by sprouted grains or microbes such as Aspergillus strains or lactobacteria, can also greatly assist in making breads, misos, kefir, and soy or amino sauces more nutritious, digestible, and free from potential residues.
January 27, 2020 – Event at Fifth Hammer
Come and ask questions of two extremely skilled fermenters and cutting edge brewers, Chris Cuzme and Mary Izett. They create their brews at Fifth Hammer Brewing Company in Long Island City.
You’ll also get to try some things that we made using enzymes, and yeasts starters. Plus, we’ll answer any question that you have about anything fermented. Of course it would be great if you had any hard core science related questions posted here, or sent to firstname.lastname@example.org beforehand so we could have a concise answer for you.
We revised the agenda based on specific requests from people about yeast starters that are useful when making a wide array of things such as beer, miso, soy sauce, meat or fish sauce, sourdough bread, vinegar, sake or kvass.
For example, someone really wanted to know about using a yeast starter for making beer. Although someone knew what sourdough bread kvass was, they asked if a yeast starter could improve it. Kvass made with fresh or old sourdough bread, heavily toasted for flavor and color, can be improved by a yeast starter, and can be flavored not only with wild herbs and roots and dried fruits but also with hops like beer.
- 1/2 gallon room temp water, left out overnight, covered, if you are concerned about chlorine or other substances.
- 4 cups of leftover sourdough starter at room temperature (most people collect it in the fridge or freezer)
- 1/2 cup Zante currants or other dried fruits such as raisins or cherries
- 2 cups heavily toasted cubed or ripped apart sourdough bread. Not burnt, but really brown.
Mix all the ingredients above in a well cleaned vessel that is able to take a doubling in volume. Unlikely, but until you’ve had to clean an overactive or over yeasted beverage that didn’t actually explode we recommend not letting it get above 80F.
Do not increase the amount of yeast. Give it space. The mixture will most likely be very thick after about an hour, at which point you will add:
- 12 cups room temperature water
- 1 – 2 cups sugar (jaggery, piloncillo, dark brown, organic cane, palm sugar, etc.)
- 1 tsp brewers yeast, or bread yeast or even unpasteurized kasu (the pressings or dregs) from a recently made sake.
Do not add more yeast unless, at four or five hours at 75F, it appears that nothing is happening. The bread wil most likely have floated up to the top, so once you mix it the yeast will grow. Because yeasts love oxygen. And the bread top may be blocking air flow. Stir.
Always cover loosely with a cloth or several layers of mesh. Do not cover tightly. Strain at 24 to 48 hours if you like the taste. It will becomes a little more sour each day.
Once you strain it – don’t discard anything – put it in bottles and chill. Do not fill the bottles to the top. Do not screw lids on tightly. After a day at 50F or less degrees, you can rack off your strained kvass.
Racking is siphoning off, or pouring off the liquid on the top and leaving the sediment. This is a standard brewing technique and it comes in very handy for a whole range of different things.
Hope you did not throw away anything. We’ll make vinegar and a beer from the dregs! Register for the January 27th event for more details and recipes.