Water kefir is a fermented drink made with water, sugar, and kefir grains. Additional ingredients such as fruits, molasses, or herbs are commonly used to create different flavors. Although water kefir is traditionally consumed in South America, Eastern Europe, and Russia, its popularity is rising due to potential health benefits. In this article, you'll find the fermentation process, benefits, and a recipe for water kefir.
Water kefir is a fermented beverage made from water, sugar, and kefir grains, showing potential probiotic effects.
Water kefir is an alternative fermented beverage for people who don't consume dairy.
Water kefir may provide immunomodulatory and anti-inflammatory effects due to its probiotic content.
Water kefir can easily be made at home by blending sugar, kefir grains, and water. It can also be customized with different fruits, herbs, or spices.
Monitoring pH, temperature, and time during fermentation is crucial since improperly fermented products contain harmful pathogens.
What is water kefir?
Water kefir is a fermented drink made with water, sugar, and kefir grains. Water kefir grains contain symbiotic cultures of bacteria and yeast (SCOBY), meaning these microorganisms mutually work and carry out the fermentation process.
Lactic acid bacteria (predominantly Lactobacillus species) form the main bacteria of the microbial ecosystem of water kefir grains. They convert sugar into byproducts such as lactic acid. This acidification gives water kefir flavor and helps preserve the beverage.
Acetic acid bacteria produce acetic acid, which adds acidity and depth of flavor to the water kefir.
Saccharomyces and non-Saccharomyces species form the majority of the yeast population in water kefir grains. Yeasts convert sugars into alcohol and carbon dioxide. This produces the natural carbonation in water kefir. The yeast also contributes to the flavor profile of the beverage.
The microbial population of water kefir is affected by fermentation conditions, including:
- Origin of water kefir
- Fermentation time
- Fermentation temperature
- Sugar sources
- Additives such as fruits and molasses
- Sanitation and growth procedures
Changes in microbial composition determine metabolite production and, thus, health properties.
Potential health benefits of water kefir
The health benefits of water kefir have been attributed to its probiotic properties.
Probiotics are living microorganisms that positively influence gut microbiota if consumed in adequate amounts. Probiotics consist of so-called friendly microorganisms, including certain bacteria and yeast. Found in fermented foods and supplements, and there are strain-specific health effects. Food sources of probiotics include yogurt, kefir, kimchi, and kombucha.
Water kefir may provide similar health benefits as milk kefir. Some research has shown immunomodulatory and anti-inflammatory effects of water kefir. However, it's worth noting that not all probiotics work the same way. Different strains of probiotic bacteria can have distinct effects. Scientists identify and study specific strains of bacteria in our gut microbiota to determine how they impact our health.
Starters, in this case, water kefir grains, may be unsafe if the source is unknown. To minimize the risk of water kefir grains containing harmful pathogens, you can buy commercially available starters that should be checked for safety.
How to make water kefir
Water kefir is often made at home since industrial products are only available in a few countries.
The ingredients are:
- Water kefir grains
- Sugar sources such as white sugar, brown sugar, cane sugar, or maple syrup
- Fruits such as dried figs (as a nitrogen source)
- Water (non-chlorinated, filtered water is recommended)
- Optional flavorings (such as fruits, herbs, or spices)
Here's a step-by-step guide on how to make water kefir. You will just need 2 tools — plastic or wooden stirring utensil (avoid metal) and a glass jar.
- Prepare the sugar solution. In a glass jar, dissolve the sugar in warm water. To prepare 500 ml of sugar solution, use 30 grams of sugar and 470 ml of water.
- Cool the solution. Allow the sugar solution to cool to room temperature. It's important not to add the water kefir grains to hot liquid, as it can damage the beneficial microorganisms. After cooling, add dried fruits and water kefir grains in a glass jar with sugar solution.
- Start fermentation. Cover the jar with rubber sealing. Place the jar in a place where the temperature is between 68–98.6°F (20–37°C). Allow the mixture to ferment for about 24–72 hours. During this time, the water kefir grains will metabolize the sugars, producing lactic acid and carbonation. Many factors, including room temperature and the origin of water kefir grains, affect fermentation time. Check for the acidity level. Fermentation can be finalized when pH reaches 4.6 or less.
- Strain the grains. After the first ferment, strain out the water kefir grains using a plastic or wooden sieve.
- Chill and enjoy. After the fermentation, refrigerate the water kefir at +39°F (4°C). It's now ready to drink and enjoy.
Remember that experimentation is part of the fun when making water kefir. You can adjust the sugar-water ratio, fermentation time, and flavorings to suit your preferences. The water kefir grains can be rinsed and used for your next batch. Follow the process from step 1 with the rinsed grains.
Dos and don'ts of fermenting
Fermented products can provide many health benefits if the fermentation is safe. Improper fermentation methods can do more harm than good. They host harmful pathogens due to improper pH, time, and temperature monitoring.
pH shows the acidity/basicity level of a solution. In the fermentation process, below pH 4.6 (acidic) should be achieved to eliminate pathogens. pH can be measured by pH meter or test strip, which should measure to at least 1 decimal point.
The proper temperature should be maintained for the whole fermentation process. Therefore, fermenting where the temperature often fluctuates is not ideal or safe. A controlled water bath incubator is a recommended device that maintains the temperature of the entire fermentation process.
Fermentation can be finalized when pH reaches 4.6 or less in a given time period. A pH meter or test strip should measure pH.
Use a water clock
Water kefir is fermented in a closed jar, so there is no air passage. A water clock helps monitor the accumulation of CO2 gas produced during fermentation. Accumulation of CO2 can break the opening of the jar. If the jar is blown, water kefir shouldn't be consumed.
You can drink water kefir to increase fermented foods in your diet. However, make sure to maintain proper temperature, time, and pH.
- Journal of Applied Microbiology. Water kefir: Factors affecting grain growth and health‐promoting properties of the fermented beverage.
- International Journal of Food Microbiology. An update on water kefir: Microbiology, composition and production.
- Office of Dietary Supplements (ODS) - National Institutes of Health. Probiotics.
- Food Frontiers. An alternative source of probiotics: Water kefir.
- Utah State University. Tips to Safely Ferment at Home.
Show all references
- The International Scientific Association for Probiotics and Prebiotics. Suggestions for Making Safe Fermented Foods at Home.