Water Kefir: A Gut-Friendly Soda?

I’ve had milk kefir, which to me tastes like a more liquidy and sour yogurt and it’s said to contain way more probiotics than regular yogurts, but I had no idea what water kefir is until a few weeks ago! After doing some quick online search, I learned that water kefir is a non-dairy fermented drink that tastes somewhat like the extremely popular drink kombucha. I consider water kefir the “cousin” of kombucha as the fermentation process, live culture, health benefit, and taste are very similar. Although both drinks have been around at least since the 1800s (or as early as 200 BC?), this cousin of Kombucha is slowly gaining more popularity back and I think it will soon catch up with its big cousin! There’re so many varieties of bottled kombucha at regular grocery stores now (and of course health food stores), but I’m yet to find bottled water kefir at any stores. Interested to find out what it’s like and whether it can be beneficial to my gut health, I decided to give home brewing a try and make some water kefir!

First fermentation on the right, bottled second ferments on the left.

Fermentation Process

After reading some reviews of several products, I found that in general starting with live culture has a better success rate than dehydrated grains. The water kefir “grains” are not really grains, but they are more like small bits of soft gel-like crystals, which are Symbiotic Cultures Of Bacteria and Yeast (SCOBY). Similarly, Kombucha uses a SCOBY to ferment as well, but the microbial species are a little different, and they look very different and more intimidating to me…

After I got the live water kefir grains in the mail, I added them to 1L of boiled and cooled tap water mixed with 1/4 cup white sugar and 1/4 tsp of molasses in a glass jar. I topped the glass jar with triple layers of cheese cloth and wrap an elastic band around the bottle neck so that the microbes can “breathe” but no flies could go in. Then I placed the jar at a warm spot on the kitchen counter, 65º – 82ºF (18º – 28ºC) is their favorite temperature range – the idea is not that the warmer the better, but the more stable temperature the better. After 1-2 days (depending on how warm your kitchen is), the liquid smelled a bit “funky” and acidic, the first fermentation is complete.

  • Boiling the water helps to remove chlorine in municipal water which may interfere with the fermentation. Make sure the water is completely cooled so you don’t kill the live culture!
  • The sugar solution serves as food for the microbes.
  • The addition of molasses feeds some minerals to the microbes so they can grow more healthily (just like us humans, they need micronutrients too). alternatively, you can use half brown sugar and half white sugar.
  • Note: I used boiling water to sterilize all glasswares and utensils to try to avoid potential contamination of unwanted microbes. And remember to wash your hands as your hands carry lots of microbes (not necessarily all bad…but you don’t want to get food poisoning by drinking a “health drink”).

Now it’s ready for an optional second fermentation if you’d like to flavour the drink and add some fizz. I used a fine mesh strainer to strain out the grains, filling the liquid to a swing-top glass bottle to about 2/3 full and fill the remaining with cranberry juice (or other fruit juice, coconut water, ginger, candied ginger, etc). The bottled ferment can go for 1-2 days on the kitchen counter. After 2 days even if you don’t reach the desire level of “fizz”, put the bottle in the fridge to stop the fermentation. Now it’s ready to drink!

  • During this process, the microbes produce CO2 as a by-product which makes the drink fizzy just like sodas – beer brewing uses the same concept.
  • When doing second fermentation on the kitchen counter, remember to open the cap at least once a day to release some gas, otherwise too much gas build-up may cause the bottle to explode and you don’t want to deal with that mess!
  • Over time as the kefir grains grow stronger and healthier, there will be more fizz and the flavor would mature.
  • For flavour ideas – so far I’ve tried cranberry ginger, lime & mint “mojito”, lemon ginger, blueberry-peach, and strawberry basil! They’re subtly sweet, very hydrating and refreshing drinks almost like mocktails!

I put the grains back to the fermenting glass jar, then repeat the fermentation process… Now I’m at my 9th ferment using the same starter culture and I can definitely tell that it has become more and more active (the first fermentation seems to be ready in less time and the second fermentation creates more fizz). Some people say that the same culture can go on for at least 6 month to a year. Others mention that as the kefir grains multiply, it can be hard to keep up with the fermentation so you may place the grains with water in the fridge to make them inert, or dehydrate them for later use, or even better – give them away to friends and family so they can start brewing as well!

Cranberry Ginger Water Kefir! Nice patio drinks 🙂

Health Benefits:

During the fermentation process, the microbes consume sugar, multiply and produce beneficial enzymes and organic acids which can help with our digestion. Also, by consuming the ferment you actually consume some of the microbes directly, which serve as probiotics and help us maintain a healthy balance of gut microbiome.

According to a literature published in the Applied and Environmental Microbiology, the most important microbial species present in water kefir are Lactobacillus casei/paracaseiLactobacillus harbinensisLactobacillus hilgardiiBifidobacterium psychraerophilum/crudilactisSaccharomyces cerevisiae, and Dekkera bruxellensis. These are all gut health promoting microbes (many of them, and their related species, are also present in other traditional fermented foods like kimchi, saurkraut, milk kefir and yogurt). In fact, another study showed that water kefir may be one of the best dietary sources of probiotics and may contain up to 56 different strains of yeast and bacteria!

Other than its gut health promoting properties, it is also said that water kefir may boost immune functions, fight certain type of cancer cells, and support weight loss (as I’m focusing on improving gut health, I did not do further research on these claimed benefits – seem too good to be true?!).

What About the Sugar?

You may think that 1/4 cup of sugar in a litre of drink seems like a lot of sugar, but after 24h of the first fermentation, the sugar is found to be completely converted by the microbes (which then becomes polysaccharides that make up the kefir “grains”). The microbes produce ethanol and lactic acid as their main metabolites (yes there’s small amount of alcohol in water kefir just like in other fermentation), and other metabolites in smaller quantities like acetic acid and glycerol, along with many aromatic compounds that contribute to the unique smell and taste of the drink.

How Much Probiotic Does Water Kefir Contain?

According to a Belgium study, a cup of water kefir can contain an average of 2- 2.5 billion CFU bacteria and 500 million to 1 billion CFU yeast. However, in another Germany study, the bacteria CFU was found to be 10 times more than the Belgium study! While there are many variables, one major difference between the two studies is that the Germany study used mineral water in the fermentation whereas the Belgium study used distilled water. This point back to the fact that microbes need their micronutrients like minerals to thrive just like we do!

Water Kefir vs. Kombucha?

In terms of the brewing process, I think water kefir is easier and more straight forward – all you do is to feed the starter with sugar water. Although I haven’t tackle kombucha brewing yet, I thought there’s more parameters to control: in brewing kombucha you have to be careful with the pH as different types of tea may have different acidity which may interfere with fermentation; it takes a longer time to ferment to maturity; and the SCOBY is a little intimidating to me as mentioned; since it floats on top it may be easier to get moldy?

As for the taste, I thought Water Kefir is milder and less acidic than Kombucha, but I do like them both and overall they’re very similar in taste to me.

Kombucha contains caffeine as it uses tea to ferment, so if you’re avoiding caffeine, water kefir may be a better option for you.

Some online sources say that Kombucha tends to have more phytonutrients like antioxidants and enzymes but less overall probiotic counts than water kefir. However I’m yet to find a controlled study that proves that. Overall, I think both drinks are great tasting and good for health so it all comes down to personal preference.


If you don’t consume fermented foods regularly and want to start trying water kefir or kombucha, you may want to start with a small quantity (no more than 1/2 cup a day) and gradually increase the dosage so your gut can adapt to this change. Some people may experience mild diarrhea or other GI symptoms at first if they don’t “ease in” to this new drink. I personally didn’t experience that.

Another call out is for people with Candida Overgrowth. If you have a yeast overgrowth, kombucha or water kefir may not be right for you as both do contain yeast (no matter it’s good or bad yeast, adding more yeast to the already overgrown population in the gut can be harmful and lead to gut microbiome imbalance).


A small business talks about water kefir’s origin, fermentation process, and health benefits.
This videos show how easy it is to brew water kefir at home! I like that there’s not much accurate measurements involved…

Leave a Reply

Fill in your details below or click an icon to log in:

WordPress.com Logo

You are commenting using your WordPress.com account. Log Out /  Change )

Google photo

You are commenting using your Google account. Log Out /  Change )

Twitter picture

You are commenting using your Twitter account. Log Out /  Change )

Facebook photo

You are commenting using your Facebook account. Log Out /  Change )

Connecting to %s

This site uses Akismet to reduce spam. Learn how your comment data is processed.