Yeast Water: A Nearly Forgotten Kitchen Essential

Make kimchi, ferment drinks, and quickly rise sourdough—all with wild yeast you create at home using Sam's simple, low-maintenance method. Unlock amazing flavors and the unique health benefits of this old-time kitchen staple.

What is Yeast Water?
Yeast water is a naturally fermented liquid made by cultivating the wild yeast found on fruit. As the fruit ferments, it creates a lively, bubbly liquid brimming with active cultures. With just a bit of patience, it becomes a wonderfully simple way to bring natural fermentation into your kitchen.

Fast Sourdough Starter:
For occasional bakers, maintaining a traditional starter can be time-consuming and resource-heavy. Yeast water, once prepared, stores maintenance-free in the refrigerator for several months. When you're ready to bake, simply combine 1 cup of yeast water, 1 cup of flour, and 1 cup of water. By morning, you'll have an "unfed" starter ready to use in your favorite sourdough recipes.

To create yeast water, you’ll need:

A clear, clean jar (no soap) with an airtight lid (essential for shaking). A one-pint canning jar works well. I take the extra step of boiling my yeast jar, then cooling it for this project just to make sure I don't get foreign hitchhikers trying to invade.

Sugar: 1 to 2 tablespoons for a one-pint jar. I've used white, brown, molasses, and honey, they all work.
(acts as yeast food and produces the carbon dioxide).

Water: only filtered, from a well, or natural spring water—no chlorine!
If none of these are at hand, take chlorinated tapwater and sit it in a sunny window for 24 hours to evaporate the chlorine.

Fruit: For a pint jar, you’ll need 1/3–1/2 cup of dried fruit.
Raisins, dates, and figs are traditional. Apples, grapes, and other high sugar fruits do well. This won't work with citrus or other high-acid fruits. Fresh fruit slices work fine, but dried fruit gives more consistent results. Organic dried fruit is ideal. Commercially dried fruit will have an oily coating and should be soaked in warm water for 15 minutes before it putting in your jar.

--A Fermenting Jar of Raisins on Day 4

Ready, Set, Go!

Place the fruit in your clean jar, then sprinkle the sugar evenly over the top of the fruit.

Add water to the jar, leaving 1–1.5 inches of headspace. The yeast will produce carbon dioxide, and without headroom, you risk a sticky explosion on your kitchen counter (jar go boom!).

Seal the jar tightly with the lid and shake it vigorously until the sugar has completely dissolved.

Set the jar on the counter in a warm spot, away from direct sunlight. Aim for a temperature around 75°F.

Mold is your biggest enemy here. To keep it at bay, shake the jar at least twice daily.
Here’s a suggested schedule:

Morning: Shake the jar well to mix the ingredients and encourage fermentation.

Evening: Shake again, then briefly open and close the lid to release any built-up pressure.

Consistent shaking during the early fermentation stages is essential. It prevents mold, ensures the yeast is evenly distributed, and helps it thrive.

How It Should Progress:

Day 1 and Day 2:
The water will be mostly clear but tinted by the fruit, with slightly more cloudiness by day two.

Day 3:
You may notice the raisins starting to float and tiny bubbles forming around them. The liquid will become cloudier as yeast develops. By the end of day three or four, tiny bubbles will appear when you open the jar, and you’ll hear a slight pressure release—signs of increased yeast activity.

Day 4:
By now, the raisins should be floating, a clear sign of active fermentation. When you open the lid, you’ll hear a fizzy sound, similar to opening a soda bottle. This effervescence indicates that the yeast is thriving and producing ample carbon dioxide. If needed, you can extend the fermentation to day 5 or 6 to allow for more activity. If you aren't bubbling and fizzy by day 6, something has stopped the fermentation. Temperature, a residual chemical in the jar, water, or fruit, or a foreign invader like mold or bacteria will likely be the culprit. Clean and sterilize your jar and give it a fresh go. It's rare that you will have a batch go sideways.

Once you get the good soda-pop fizz when you open the jar, the yeast water is ready!

Strain the contents through a sieve or cheesecloth and pour the liquid into a clean glass container with a tight lid.

-- A Jar of Yeast Water Ready for Use: (ok, a 1/2 jar)

Storage and Maintenance:
Your yeast water can be stored in the fridge for up to 3 months. Shaking it occasionally, especially if it starts to settle, will extend it's life and discourage mold. To make a fresh batch, simply take a tablespoon from the old jar and add it to a new jar of fruit, sugar, and water. This will give your next batch a head start.

To Turn Yeast Water into a Sourdough Starter:

1/2 cup of yeast water
1/2 cup of water
1 cup of all-purpose or bread flour

Mix these ingredients in a jar or bowl with a loose cover. Place the mixture in a warm spot (70°F or higher). Within 8–12 hours (overnight), your starter will be ready to bake and can be used just like a traditional unfed sourdough starter.

This newly created sourdough starter can also be maintained like a traditional one. And if you forget it in the fridge and it starves, don’t worry—it’s quick and easy to whip up another batch with your yeast water.

Yeast water opens up a world of possibilities beyond sourdough. It's a connection to the rich traditions of fermentation that bring health, flavor, and creativity into your kitchen.

-- A Batch of Russian Kvass - Healthy and Deliciously Bubbly!

Incorporating fermented foods like yogurt, kimchi, and sauerkraut into your diet offers numerous, well established health benefits. Foods prepared with fermentation are rich in probiotics, which in turn support gut health and promote a balanced microbiome. This balance aids digestion and enhances nutrient absorption. Fermenting can boost your immune system, help control blood sugar levels, may even reduce the risk of heart disease. Fermented food is truly nature's pharmacy. If you would like to research further, here is a great study to get you started on the benefits of adding naturally fermented foods to your diet:

Fermented foods: An update on evidence-based health benefits and future perspectives

Next week, I’ll put up some favorite recipes and unique uses for your yeast water. Kimchi, kvass, homemade (and healthy) sodas, and of course, baked goods. Grab a jar, some fruit, a little sugar, and let nature work her magic.

Happy fermenting!

--SourdoughSam

www.sourdoughsam.com - for recipes, original stories, traditional skills, and country humor.

Yeast Water: A Shortcut to Sourdough and Much More