Using Wild Yeasts for Fermenting Foods and Beverages

By: Nigel Thomas

We should all have an appreciation for our microscopic single-celled fungal friends known as yeasts. Credit goes to them for some of our most culturally important foods and beverages. The seemingly magical power of yeast is what leavens our breads and ferments our beers and wines. Without these organisms we would never enjoy a light airy loaf of bread, or experience the pleasant buzz of a glass of wine. Today most breads, beers, and wines are produced using commercial produced isolated yeast strains, giving highly predictable and consistent outcomes. But you don't need to go out and buy any of these proprietary yeasts when you want to create a yeasted product at home!

The world all around us is filled with an abundance of wild yeasts. They can be found on fruits, flowers, leaves, our own skin, and just about everywhere else. Even the air we breathe carries yeast. Wild yeasts do not offer the same predictability relative to flavor or time that commercially available yeasts will. However, they make up for this by leaving you with a truly unique and often spectacular end result. Fortunately for us it is simple to harness the power of yeast.


Have you ever noticed the whitish bloom (or powder) on the skins of grapes of blueberries? Those are wild yeasts! This week I harvested a few hand fulls of ground juniper berries that were covered in a thick white bloom and decided to use them for a some yeast fermentations at home. The amount of yeast present on the small amount of berries I had gathered was not sufficient to raise a loaf of bread or start a batch of wine. In order to generate an adequate population, I propagated the yeasts by throwing the juniper berries into a jar full of lightly sweetened water. The sugars in the water supply food for our yeast (if fruits with a high sugar content are used, added sugar may not be necessary). Once your yeast source is in the water, all one must do is shake the jar a few times a day and wait. Shaking the jar aerates the solution, giving the yeasts the oxygen needed to multiply. After 3-7 days of shaking, the water should be bubbling with life and full of living yeasts. This “yeast water” can be used for fermenting beverages and baking bread. This week I used my yeast water to leaven my breads and started a few sodas, beers, and wines. Working together with our wild allies is incredibly satisfying and fun. Delicious too!


If you are interested in learning more about yeast water and other fermentations: join us for our lacto-fermentation workshop on March 31. In this workshop we will cover all of the basics of lacto-fermentation techniques and touch on yeast dominated fermentation. There will be plenty of delicious ferments to taste and you'll make a few to take home for yourself!

Find out more and register for the workshop by clicking here.