How to Prepare Water Kefir

Water kefir, not to be confused with milk-based kefir, is fermented using water kefir “grains.” Just like milk kefir grains, water kefir grains are not real grains. They are colonies of yeast and bacteria that are somewhat translucent and shaped like miniature cauliflower florets. Water kefir grains require only water and sugar to ferment. While activating dehydrated kefir grains (explained in instructions below) can take two to three weeks, once the grains are active, the fermentation process goes relatively quickly. This dairy-free beverage is an outstanding method for taking in probiotics, staying hydrated, and detoxifying the body!

Similar to most beverages in this book, water kefir can undergo a secondary fermentation, which makes it fizzy. This beverage is known as kefir soda. Once the primary fermentation is complete, you are free to stop there and enjoy the water kefir, but flavoring water kefir for the secondary fermentation is fun and gives the naturally bubbly beverage a lot of spunk.

If you don’t know anyone who makes water kefir, you will need to purchase dehydrated kefir grains. There are many reliable water grain sources on the Internet. To be effective for fermentation, dehydrated water kefir grains need to be rehydrated and activated. This process can take quite a while (one to three weeks), but once the grains are active, they can be used over and over again to make probiotic sodas.

Health Benefits of Water Kefir and Kefir Soda

Aside from its probiotic density, water kefir (and kefir soda) is a very hydrating beverage and is a great replacement for electrolyte sport drinks, as it contains enzymes and minerals. Water kefir helps reduce inflammation, thus easing any digestive discomfort and also helps relieve skin irritation such as eczema and acne. Drinking water kefir is also wonderful for detoxification, as the beverage helps clean out the liver. 

Secondary Fermentation

After the water kefir is finished fermenting, you can either consume it immediately or add ingredients to allow it to go through a secondary fermentation. This process will generate kefir soda as long as there is ample added sugar (from fruit, fruit juice, or cane sugar) and/or fruit pulp, which will make the water kefir fizzy. Secondary fermentation for kefir soda takes between two and three days and results in a wonderfully effervescent beverage. 

It is always wise to be careful when opening bottles after secondary fermentation, as pressure builds and liquid can fizz out. Be particularly careful if using flip-cap bottles because these bottles are so air-tight that they tend to seal pressure in almost too well. When opening a bottle of kefir soda, always point it away from your face and away from other people. I do not recommend handing a bottle of kefir soda to a child to open.

Flavoring Water Kefir or Turning it into Kefir Soda

Water kefir tastes the best when it is flavored. Without added ingredients, water kefir has a slightly sweet, lemony, and yeasty flavor, which can be an acquired taste. Adding fruit juices or whole fruit, herbs, or teas allows you to cater the flavors to your pallet. If you know you like sweeter beverages, be sure to add a little extra juice or fruit prior to sealing the bottles for secondary fermentation so that the probiotics have enough sugar to ferment a second time with some leftover sweetness for you to enjoy.

The easiest way of flavoring water kefir is by adding 100 percent pure juices prior to bottling it for secondary fermentation. About 1 cup of juice per 4 cups of water kefir provides good flavor and plenty of fizziness. It seems as though all probiotic drinks love fructose more than sucrose for secondary fermentation. Water kefir will become kefir soda and yield the fizziest results when fruit and/or fruit juice is added to it prior to secondary fermentation.

Important Precautions

Kefir grains react in a very adverse way to metals. For this reason, be sure to avoid metal touching water kefir liquid or grains at any time. When straining the water kefir to separate it from the grains, always use a fine plastic strainer, which can be purchased at most kitchen and home stores or online. 

Use a glass jar or jug for fermenting the water kefir. Glass is easy to sanitize and it doesn’t trap bacteria, chemicals, or BPA. You want to avoid anything contaminating your probiotic drink and the best way of doing so is to brew it in glass.

If at any time your water kefir smells rancid or similar to rotten milk, your batch has gone bad and, unfortunately, you need to start over with new grains. During the first day or two of fermentation, the liquid will not have much of a smell, and by the third or fourth day, it will smell lemony and yeasty. The odor should never be off-putting or foul, and as long as you follow the instructions carefully, you won’t have a problem.

Like most probiotic beverages, water kefir prefers to be at room temperature to ferment, which is typically in the high-60s to mid-70s. The jar the water kefir is fermenting in should never feel warm to the touch—if it does feel warm, you run the risk of killing the probiotics.

Similar to bread yeast (or really any live culture), it is definitely possible to kill the water kefir culture if you use too much sugar in your sugar water solution. You may have the intention of giving the water kefir grains an extra boost or treat, but using more sugar than what is recommended in these recipes may result in your water kefir grains dying and/or killing the probiotics in the drink.

While you should keep the water kefir in a clean environment, you do not need to sanitize the jar the water kefir brews in between batches (the same is true for brewing kombucha and jun). As long as the culture you are brewing is healthy, the probiotics will prohibit bad bacteria from growing in the jar, which makes sanitizing it between batches unnecessary. Nevertheless, I do recommend cleaning the jar out every few batches for peace of mind, as slimy film will form on the edges of the jar. This is perfectly normal, but for safety purposes, a good cleaning with hot water and soap is recommended from time to time.

The instructions below describe how to make water kefir from start to finish, followed by recipes to make delicious probiotic soda flavors. We start by activating kefir grains, followed by making water kefir, and then allow the water kefir to go through secondary fermentation to turn it into a fizzy “soda.”

More from Delicious Probiotic Drinks:

Excerpted from Delicious Probiotic Drinks: 75 Recipes for Kombucha, Kefir, Ginger Beer, and Other Naturally Fermented Drinksby Julia Mueller, with permission from Skyhorse Publishing, Inc. Copyright 2014 by Julia Mueller. Photographs by Julia Mueller.

Delicious Probiotic Drinks

The health benefits of probiotics are no secret. Doctors from both the Western and Eastern medicine camps sing the praises of probiotics for their positive effects on digestion, metabolism, and the immune system. Enthusiasts of kombucha point to its high levels of B vitamins and amino acids, improving mood, energy levels, joint function, ligament health, and skin health. Now you can learn to make kombucha, as well as numerous other probiotic drinks, at home!

With clear step-by-step directions, beautiful photographs, and more than 75 recipes, this is the ultimate guide to homemade probiotic drinks.

In addition, you’ll find recipes for making yogurt, smoothies, and kefir ice cream. Fermenting drinks may seem daunting, but Julia Mueller shows how it can be fun, much more cost-effective than buying ready-made drinks from the store, and delicious!

Published on Apr 8, 2019


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