Fermented Foods: Kefir, Kombucha, Kvass, Sauerkraut, Yogurt

Fermentation of food is a traditional technique for food preservation used for thousands of years. During fermentation, beneficial microorganisms pre-digest food to increase nutrient value and change the micro-environment of the dish to be inhospitable to pathogens. The bacteria used for fermenting are generally similar to those found in a healthy human digestive tract and most commonly include varies species of lactobacilli. The lactobacilli lower the pH to levels heading towards the low pH of stomach acid. As a result, many detrimental microorganisms cannot survive but beneficial ones can. In the process of breaking down the food, the bacteria break down proteins into readily absorbed amino acids and create many vitamins (especially B vitamins and vitamin K2 bacterial forms) that human cells can’t make.

Many fermented foods are consumed directly without further preparation such as cooking that would kill the beneficial bacteria and yeasts. These foods can work as an alternative to probiotics and prebiotics, with major advantages in the microorganism count. A serving of a fermented food might contains trillions of beneficial bacteria of dozens of different strains along with foods they can digest. A probiotic capsule might contain a few hundred million to tens of billions of bacteria but often include only one or several strains of bacteria. So you could view fermented foods as a “make it yourself” type of probiotic that can be highly cost effective.

There are some high-end probiotics that boast around 100 billion microorganisms per capsule with dozens of strains and even a little bit of food (prebiotics) to keep them alive. They tend to be priced on the order of $1 per capsule which might be a little expensive if you want to be consuming hundreds of billions of beneficial microorganisms per day. A couple of good examples of such high-count probiotics are Garden of Life RAW Probiotics Ultimate Care and Renew Life Ultimate Flora Critical Colon. Both are well-reviewed by their customers, and may be good options even for fans of fermented foods for those times they are travelling and can’t lug around glass jars of their favorite ferments. Fermented foods can take the place of at least some of the probiotics you may be using, and might save you some money while offering a wider variety of beneficial bacterial species.

Bacterial Health Benefits

Some doctors are starting to catch on to how valuable fermented foods, probiotics, and prebiotics (food for bacteria that humans don’t digest directly) are to health. Neurologist Dr. David Perlmutter in his book Brain Maker: The Power of Gut Microbes to Heal and Protect Your Brain–for Life goes through the science of how gut bacteria are essential to health. He discusses how common practices such as C-section deliveries of babies and using antibiotics for minor infections have wrecked the health of many people.

He offers numerous case examples of people with serious health problems (including hard-to-treat neurological problems such as multiple sclerosis and autism) who benefited from fixing their gut bacteria by consuming fermented foods and using probiotic and prebiotic supplements. He’s a huge fan of fermented foods, but also advocates using probiotics not just by the usual means of swallowing capsules but also in probiotic enemas which have produced some amazing results in his patients. One example is the boy with autism who barely talked who, after using probiotic enemas, was able to chat comfortably with his mother during her hair-dressing appointment, something he had never done before in his life.

Dr. Perlmutter is so convinced of what bacteria can do to improve human health that he worked with Garden of Life to formulate products of the sort he would like to offer to his own patients such as 90 billion count probiotic capsules including 15 important bacterial strains and organic prebiotic fiber to feed those bacteria.

As you’re better off consuming fermented foods frequently rather than relying solely on probiotic supplement capsules, his book include many recipes for foods using fermentation that feature ingredients that help feed healthy gut bacteria. It also offers a sample meal plan to help you get your diet on a good path.

Special Probiotic Products

Even if you are eating a variety of fermented foods every day, there are still some probiotic products that may be helpful. Dental probiotics and probiotic skin care products aim to build up the good bacteria in your mouth and on your skin that can help keep those areas of the body healthier.

Dental probiotics that include special bacterial strains such as BLIS K12 and BLIS M18 are shown in studies to significantly help reduce throat and upper respiratory tract infections and plaque buildup. They may also reduce the risk of cavities because these strains produce biochemicals that tend to kill off some pathogenic bacteria such as the Streptococcus mutans that is often blamed for cavities. Products that include BLIS K12 and BLIS M18, such as Great Oral Health Advanced Probiotics and Dental ProbioticVita, are small tablets that you dissolve in your mouth after brushing your teeth. This populates the teeth, gums, and mucous membranes in the mouth and upper throat with these special beneficial bacteria that are not likely to be found in common fermented foods.

There are several probiotic skin sprays and soaps on the market now. Some, such as Dermatic, are aimed at clearing up chronic skin problems such as eczema. Others, such as Dr. Ohhira’s Probiotic Kampuku Bar Soap, are intended more as general-purpose soaps that can repopulate and maintain healthy skin bacteria. Consider such products as better options than buying antibiotic soaps that will wipe out the healthy bacteria, leaving your skin open to infection by pathogenic bacteria.

Fermented Foods Are Safe

You may wonder how fermented foods can be safe if they are not cooked given all you have been told over the years about how bacteria are bad and cause infections. These are common misconceptions about bacteria spread by the conventional food and medical industries that often advocate killing all bacteria with poisons like anti-biotics (mold toxins that kill bacteria and hurt human and animal cells, too). According to Sandor Katz, a top expert on fermentation, there has never been a documented case of food poisoning from fermented vegetables. How can this be? If you get the fermentation started right and make sure it is sealed well so it doesn’t get exposed to air during the ferment, the bacteria will lower the pH so far that pathogens can’t survive in numbers large enough to cause illness. If the seal fails and mold starts to grow in a vegetable ferment, you can tell that the batch is spoiled and should use it in your compost pile because the molds growing might not be safe.

General Guidelines For Fermentation

Fermented foods should be grown in glass or ceramic containers and handled using plastic or wood utensils. Metal of any type in contact with the food — such as containers, spoons, and strainers — is likely to react with the acidic conditions and taint your ferment with unhealthy metals as well as hurt the microorganisms.

Water that you use in ferments should be from a filter that gets rid of chlorine and other contaminants. Tap water is never suitable for fermentation as it will harm or kill many beneficial bacterial species.

Fermented Foods From Cultures Around The World

There are a huge variety of fermented foods from cultures around the world. They include beverages, cheeses, breads, meats, condiments, vegetables, and more. Probably the best book on the wide range of fermented foods is The Art of Fermentation: An In-Depth Exploration of Essential Concepts and Processes from around the World by Sandor Katz. It’s a massive 500+ page collection of information on the history, science, and practice of fermentation for foods and other purposes. Here are a few freely available interviews with Sandor Katz for you to enjoy:

The Art of Fermentation Sandor Katz Interview

Dr. Mercola Interviews Sandor Katz about Fermentation

Sandor Katz – Why Fermented Foods Help Improve Health & Digestion

Sandor Katz – The Art of Fermentation – Cornell University on April 2, 2012

Real Food Fermentation: Preserving Whole Fresh Food with Live Cultures in Your Home Kitchen is recommended book for beginners learning how to ferment foods, but does not have the immense breadth and depth of the Katz book. Depending upon your level of knowledge and interest, this might be an advantage or disadvantage.

Among the more popular known fermented foods you may find are kefir, kimchi, kombucha, kvass, natto, pickles, sauerkraut, sourdough bread, and yogurt. Some of these are briefly described below along with sources for the microorganisms, information, and supplies you need to get started.


Kefir is an Eastern European fermented food that is often prepared from dairy milk, such as from cows, goats, and sheep. Generally it is prepared as a drink, but it can also be used to make thick drinks much like yogurt and even cheese. It can also be made from water with sugar, coconut milk, juices, and some other liquids that have enough sugar to support the kefir culture. A “SCOBY” (Symbiotic Culture of Bacteria and Yeast) is grown with relatively controlled conditions (such as using sterilized milk so the bacteria in raw milk won’t compete with the kefir culture) until it gets well-established enough that it can support fermenting the food liquid chosen. Since the SCOBYs for kefir often look like mashed rice or cauliflower, they are usually called kefir grains.

Some vendors supply a dehydrated starter that you’ll have to grow into grains. Others provide an established set of grains that must be reinvigorated and possibly grown a bit larger to make it ready for fermenting your choice of beverage. The dehydrated starters are often regarded as easier to use for newbies, but often do not include as wide a range of microorganisms and are less capable of supporting long-term reuse. Some say the kefir it produces is not as tasty as from kefir grains. So if making kefir is something you plan to be doing for the long term, you might just start with the kefir grains rather than the dehydrated starter. Milk kefir grains work best with dairy, water kefir grains work best with water plus sweeteners such as sugar, molasses, and fruit juice.

How to Make Kefir – A Beginners Guide is a helpful guide to getting started with making various kefir drinks, cheeses, and desserts.

Well-reviewed kefir dehydrated starter products include:

Poseymom’s Dehydrated Organic Water Kefir Grains

Wilderness Family Naturals Kefir Culture Starter

Yogourmet Freeze Dried Kefir Starter

Well-reviewed kefir grains (SCOBY) products include:

Poseymom’s TRIO of Water Kefir grains, Milk Kefir grains, and Kombucha SCOBY

Lifetime Kefir Milk Kefir Grains

Active Organic Milk Kefir Grains & plus “Milk Kefir Unleashed” Ebook

Strainer for Filtering/Saving Kefir Grains

Culina Nylon Mesh Strainer – 4 inch
Culina Nylon Mesh Strainer Set of 3 – 4 in., 5½ in. and 7 inch


Kombucha is a fermented tea drink. Many people who like it comment that it is like a healthy soda because of its bubbly composition. The tannins in the tea help certain microorganisms to become dominant. Sugar and usually some other flavorings are also added to the tea to provide a source of energy for the microorganisms and enhanced flavor to the drink. Commercially produced kombucha such as the GT’s Kombucha brand often use just a couple of microorganisms, the beneficial yeast Saccharomyces boulardii and the spore-forming bacteria Bacillus coagulans (aka Lactobacillus sporogenes). The yeast makes alcohol and carbon dioxide. The bacteria turns the alcohol into acetic acid so there is less than 0.5% alcohol left in the drink.

Generally you can find this kind of commercial kombucha for around $3-4 per pint bottle if you shop locally, which makes it an expensive replacement for the cheap toxic commercial sodas that so many people drink. Fortunately, if you make it yourself you can bring the cost down tremendously to more like $3-4 of ingredients for one or more gallons per brew. Your initial investment to obtain a culture (SCOBY) and some containers and strainers (glass and plastic, never metal) is probably going to be around $50 or less to get started.

You might be concerned about the idea of drinking live yeast if you have had candida infections or other health problems with yeast. Saccharomyces boulardii, however, has developed a reputation as a therapeutic probiotic that has potential to help prevent or reverse candida overgrowth as well as help fight many kinds of gastrointestinal problems such as diarrhea, Clostridium difficile infection (which causes extreme and potentially deadly diarrhea), and other pathogenic GI infections. The article Efficacy and safety of the probiotic Saccharomyces boulardii for the prevention and therapy of gastrointestinal disorders is a helpful overview of some of the medical studies on this yeast.

Many kombucha fans do a second pass fermentation for a few days to add flavor and carbonation. They take the half gallon or larger amounts of basic kombucha and then pour it into smaller bottles with a small amount of a flavoring such as sliced fruit and/or ginger root. The SCOBY is left in the original ferment container with some of the kombucha. You brew up more tea, add sugar (fuel for the yeast and bacteria to ferment), let it cool to room temperature, and then pour it into the container with the SCOBY to start your next batch. Fresh fruit such as strawberries and figs are popular. Dried fruit often works well, as does thawed frozen fruit. Be careful to use fruit that does not have any preservatives that might kill off the kombucha culture.

If you start out trying GT’s Kombucha (the ginger flavor is now available in many Costco stores), be sure to save the bottles for your own brewing. You can use them for your second-pass fermentation to add your own favorite flavors (and build up some bubbles) by using suitable replacement bottle tops.

Kombucha Revolution: 75 Recipes for Homemade Brews, Fixers, Elixirs, and Mixers is a helpful book on making kombucha.

Well-reviewed kombucha SCOBY products include:

Kombucha Kamp Kombucha Culture

Organic Kombucha Scoby – Live Culture

Kombucha Starter Kit with Organic Kombucha Scoby. 1 Gallon Kombucha Jar, Organic Kombucha Loose Leaf Tea, Temperature Gauge, Organic Sugar and More

Bottles for storing brewed kombucha:

32 oz. Clear EZ Cap Kombucha Bottle
32 oz. Amber EZ Cap Kombucha Bottle
32 oz. Cobalt Blue EZ Cap Kombucha Bottle

Bottle Caps for Second Fermentation

38mm poly seal caps suitable for use on GT’s Kombucha bottles

Funnel and Strainer for Bottling Kombucha

OXO Good Grips 3-Piece Funnel and Strainer Set


Sauerkraut is German-style fermented vegetables, specifically cabbage but more generally it can include other veggies and even some fruits. Some nice additions to the basic cabbage are beets which add sweetness and a wonderful deep red-purple color, carrots, and even apples. Sometimes spices, such as a caraway seeds, are added to the veggie mix prior to fermenting.

Unlikely many ferments, sauerkraut often is made simply using the natural bacteria already on the vegetables. Most of these should be lactobacilli that make lactic acid that makes the fermenting food inhospitable to yeasts and some other bacteria. A significant amount of salt is used to get the mixture started to help impede the growth of yeasts until the pH drops low enough to keep them from growing. Some people who have trouble breaking down histamine may have trouble with consuming sauerkraut because many lactobacilli make histamine. If you experience allergy type symptoms such as a runny nose and congestion after eating sauerkraut, this is a sign you may have an intolerance to histamine. Fortunately, there are bacteria compatible with sauerkraut ferments that break down histamines. You can use these to help lower the histamine level in the sauerkraut. Suitable species of histamine degraders include Lactobacillus gasseri, Lactobacillus rhamnosus, Lactobacillus salivarius, and Bacillus coagulans (aka Lactobacillus sporogenes). You can buy these as capsules and add them to the sauerkraut mix before you pack it into the fermenting containers. To save money and accelerate the fermentation of future sauerkraut batches, you can save some of the sauerkraut juice from one batch to use in the next batch to help load it up with the histamine degrading bacteria.

The video The Art of Fermentation with Sandor Katz features a four minute long demonstration of preparing sauerkraut by Sandor Katz along with discussion of benefits of fermentation.

To prepare the veggies, you’ll need a cutting board, a knife, and a large mixing bowl. Cut up the cabbage into thin pieces, then put it in the mixing bowl and mash it with a spoon or a sauerkraut masher or vegetable pounder. You want to mash it enough that lots of juices are coming out. Cut up the rest of the veggies in small pieces, then put them in the mixing bowl. Add salt (preferably low-aluminum pickling and canning salt or sea salt), roughly 2 tablespoons per 5 pounds of veggies, then mix well.

Add any new probiotics you want to put into the sauerkraut by opening up the capsules and sprinkling the contents in and then mixing again.

If you have leftover sauerkraut juice from a previous batch that turned out well, mix that in, too. This will accelerate the ferment and help load it up with any beneficial probiotics that you added in previous batches. Don’t do this if you were not happy with the results of a previous ferment as it could be the batch had a suboptimal mix of bacteria.

Wide mouth jars are usually the easiest ones to pack with sauerkraut, but if you have standard mouth jars they can also work. Quart size jars are a good choice, but if you’re eating a lot of sauerkraut then half-gallon might be better. Pack the sauerkraut mix in the jars, leaving at least an inch of space at the top for bubbles to expand the mix. But don’t leave a lot more space than this at the top of the jars because the extra air makes it more likely that yeast will grow on the top of the mix.

To help prevent the sauerkraut from spoiling from yeasts that can use the oxygen in the air, there are three techniques that when combined get a good result. One is to make sure you pack down the mix very well so that there is standing water with salt on the top. A second step is to put a cabbage leave on the top to keep any floating veggie pieces from rising to the top. Since there can be a lot of gas bubbles made during a ferment, there is still a risk of floaters that may feed yeast. To further reduce this risk, a third step is to put fermenting weights on top of the cabbage leaves.

It is possible to make sauerkraut without these weights, but from experience you do run a higher risk of spoiling a whole batch with mold or yeast especially if the temperatures in your fermenting area are above the mid-70s Fahrenheit and/or you live in an area with high humidity that probably has a lot of mold spores floating around in the air.

When fermenting, you would be well-advised to put the jars into a tray or bin that can catch any overflow liquid. It’s a lot easier this way to clean up the mess when a batch gets fermenting fast and generates a lot of bubbles that push the liquid out of the jar.

Let ferment for a few days to a few weeks. Typically in an environment at comfortable room temperature (around 70-75 degrees F), a week is a good amount of time. But it depends a lot upon your taste.

After fermentation has reached the stage you like, put the containers in the refrigerator and open up and use one container at a time. The fermentation will continue in the refrigerator, but at a vastly reduced rate. From experience, the sauerkraut continues to be fine for at least two months when refrigerated apart from when you take it out to serve. It can last much longer if it is refrigerated without opening. According to Sandor Katz, storage of unopened containers outside the refrigerator for multiple months is possible if the temperature is consistently in the 55-65 degree range such as you might find in a basement.

Jars for packing sauerkraut:

Kerr 0519 wide mouth jar quart, 32oz (case of 12)
Ball Wide Mouth Half Gallon (64 Oz) Jars with Lids and Bands, Set of 6
Ball Wide-Mouth Plastic Storage Caps, 8-Count (not water or air tight without seals below)
12 Mason Jar Reusable Silicone Seals for Plastic Caps (Wide Mouth)

Special airlock wide mouth mason jar tops (not required, but may improve results)

Kraut Kaps© 3 Pack – Platinum

Vegetable masher/pounder

Small Wooden Cabbage Tamper for sauerkraut and more
Vegetable Stomper – Vegetable Pounder

Fermentation weights

Pickle Pebbles 4 Pack – Glass Fermentation Weights
Fermentation Glass Jar Weights 4 pack 2 1/2″ to fit a wide mouth quart jar

Histamine-degrading bacteria probiotics to help produce lower histamine sauerkraut:

Lactobacillus Gasseri 3 billon CFU, 60 capsules
Lactobacillus Rhamnosus 5 billon CFU, 60 capsules
Lactobacillus Salivarius 18 billon CFU, 100 capsules
Source Naturals Dura Flora Bacillus Coagulans 5 Billion Cells, 120 Capsules

Vegetable Start Culture (not required, but may give better results)

Culture Starter by Body Ecology
Mercola Kinetic Culture

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