Fermented vegetables are made with lactic acid bacteria, which is a valuable technique humans have been using for thousands of years. This preservation method has numerous health advantages. Fermented vegetables are rich in nutrients, fiber and digestion-enhancing enzymes. They also help the intestinal tract maintain a healthy balance of flora by increasing beneficial bacteria.
The simple and natural process of lactic acid fermentation now is being rediscovered, especially by those who are aware of the failures of the modern diet. One only has to observe health statistics briefly to become aware that the American diet must change if we are to live full and productive lives. The consumption of fermented vegetables addresses numerous dietary and health issues simultaneously.
You’re probably familiar with sauerkraut — it’s the most common fermented vegetable product. There are several reasons for sauerkraut’s popularity; consider its unique taste, legendary nutritional and medicinal properties and the ease with which it’s made.
Sauerkraut barely begins to tell the story of fermented foods — a story that repeats itself around the globe, from the pungent flavor of Korea’s kimchi to Tanzania’s fermented gruel, togwa.
History of Fermented Foods
Lactic acid-fermented foods, including dairy products like buttermilk, cheese and yogurt, have been around throughout recorded human history. The processes that produced these foods were found to occur quite naturally — though they’ve been refined over time. Additionally, it was discovered that fermented vegetables kept longer and also took on interesting characteristics that added to the enjoyment they provided.
In Korea and other Asian countries, a pungent condiment called kimchi is eaten in small amounts with many meals. Kimchi is composed largely of cabbage but contains other vegetables as well. Spices are added for flavor and additional preservation.
The Chinese have been fermenting cabbage for thousands of years. It was used in ancient Rome and in medieval Europe. Genghis Kahn used it around a.d. 1200, and it was consumed in 18th-century sea voyages to prevent scurvy on long excursions.
In Southeast Asia, where food spoils rapidly, lactic acid fermentation also is used on fruits and fish. In Japan, the popular miso is a fermented combination of soybeans (normally often hard to digest), rice and barley. In Russia and the Balkans, fermented vegetables are extremely common.
In Tanzania, people eat a fermented cereal gruel called togwa. It is used both as a complementary food and soft drink. Studies involving children have focused on togwa’s effect on diarrhea, a common ailment due to unsanitary conditions. A study confirmed that eating togwa conferred 14-day protection against diarrhea.
In Bulgaria, a study of centenarians showed they consumed a diet high in bulgaricus-containing yogurt. Many similar case studies appear from around the world.
Fermenting Vegetables for Preservation
Perhaps the most important reason vegetable fermentation became popular was for preserving vegetables through the winter. The idea probably caught on because of the benefit of having “fresh” vegetables during lean times.
Today, this method still provides us with the most nutritious means of preservation. Because cooking is not involved, the vegetables’ nutrients are retained. The ease with which fermented vegetables are digested enhances their benefits. With proper planning, a supply of vegetables can be available throughout the winter. Many people love the taste of fermented vegetables, but for some it may be an acquired taste. Sauerkraut might appeal to the reluctant a bit more once they realize how healthy it is.
Basic Vegetable Fermentation Techniques
The main keys to successful fermentation are salinity, temperature, nutrition, cleanliness, darkness and an oxygen-free environment. Carbon dioxide will be given off, especially initially, which replaces the oxygen. The presence of oxygen may allow kahm yeast to grow, which usually appears as a fuzzy white ball. This is harmless, but because of its taste, it should be removed every 10 to 14 days. The inconvenience of this process might be why people began using other methods of preservation.
Almost any vegetables can be fermented. Organically grown vegetables are a superior choice: They’re free from synthetic pesticides, herbicides and fertilizers and contain more lactic acid bacteria. It’s helpful if they’re shredded, sliced or cut into small pieces first — this accelerates the fermentation process by exposing more surface area to the broth. It also allows for greater compaction in the container. Vegetables should be crushed to release their juices. However, it’s also possible to ferment whole vegetables, such as beets.
Most vegetables require whey to provide adequate bacterial nutrition. Whey is the liquid portion separated from sour milk, buttermilk, kefir or yogurt. You can use a few layers of cheesecloth to separate out the solids, or curds. The best source of whey is from unpasteurized milk left in a warm place for a couple of days to sour. The only vegetables that do not require added whey are cabbage or cucumbers grown in warm, humid conditions.
Cabbage is the most ideal vegetable for fermentation, since it contains an abundance of lactic acid bacteria, as well as a good amount of vitamin C and some vitamin A. Onions and tomatoes are good complements for fermentation with other vegetables. Fermented onion is mild and relatively easily digested.
Vegetables should be well rinsed, and root vegetables should be brushed. Be sure to use chlorine-free water; if your tap water is chlorinated, boil it for at least 10 minutes, then allow it to cool.
You’ll also need to have non-iodized salt on hand. Sea salt is a good choice, as it provides additional minerals. Your hands, utensils and containers should be as clean as possible and well rinsed of residual soap.
Salt prevents both the overgrowth of yeast and the breakdown of vegetable proteins before enough lactic acid builds up to have a preservative effect. When making fermented vegetables, the salinity requirement is 1 to 11/2 teaspoons of salt per 2 pounds of vegetables. Saline water (1 tablespoon of salt per quart of water) should be added to cover the vegetables by at least an inch.
A proper initial temperature is 68 to 72 degrees for two to three days, which starts the fermentation. Then store the vegetables at 58 to 64 degrees for four to six weeks. After this time, it’s good to store them at 40 to 60 degrees, which is adequate for keeping the vegetables for a year or more.
Seventy degrees is the average comfortable household temperature. A location out of the sun is preferable, and a low kitchen cabinet works nicely. (By using a low cabinet, ideally next to the floor, the temperature is most stabilized. A northeast corner of the house is also most stable.) In a non-air-conditioned house, the north side of the house will work better in warmer weather. A cellar or basement is very nice to have for the second stage, or even the storage stage, since the earth’s temperature at that level is around 60 degrees.
The vegetables’ flavor continues to improve over time. When the vegetables are ready and you want to eat some, remove from the crock only what you’ll consume in a week or two, and store this in a jar in the refrigerator. This minimizes air contact with the stored vegetables.
Common spices for flavor include dill, mustard seed, juniper berries, caraway seeds, bay leaves, red pepper, coriander and many others. Raspberry leaves offer lactic acid bacteria as well as flavor. In the delicious Russian Sauerkraut recipe on Page 38, whey is not needed because there is enough cabbage present, and the combination of vegetables is very nutritious. Sliced horseradish root is added for its preservative qualities as well as its flavor, and often this is layered on top of the vegetables.
Containers Used in Fermentation
The material of the container used in fermentation should be nonporous for easy cleaning. If you choose a plastic container, it should be food-grade, which prevents the plastic taste from getting into the vegetables. Avoid fermenting in tightly sealed containers, or an explosion could result due to carbon dioxide buildup.
If using jars with screw-on lids, the lids must be very lightly screwed down during initial fermentation. If the jars are carefully tended, the lids may be screwed down more tightly after the initial period of active fermentation. This may be difficult to gauge, and individual jars may experience different rates of fermentation. Push down on the lids — if they are popped up and you feel any resistance, release the gas by loosening the lids. Be careful when attempting this technique and keep the jars covered with a towel to protect yourself. Do not handle the glass directly until the fermentation is complete.
The most convenient container choice is the Harsch crock, made by the German ceramic company Sudkeramic. This crock uses a V-shaped gutter, in which the lid sits. The gutter is filled with water to provide a seal while allowing gas to bubble out. The Harsch crock comes with weighting stones that keep the vegetables compressed and submerged.
The Harsch airlock is roughly similar in concept to one used by home brewers, in which an inexpensive S-shaped water-filled airlock allows gas to escape. I haven’t tried to adapt one of these to a food-grade plastic bucket, but this might be the least expensive option. These buckets are often available for free from supermarket bakeries. To keep out oxygen, you can use an open bucket with water-filled garbage bags (double-bagged for protection) to serve as lids. This forms a seal around the edges and allows gas to escape.
Fermenting vegetables provides preservation, nutrition, flora, fiber, ease of digestion and flavor. The recipes can be made in both large and small batches. You can eat fermented vegetables by themselves, as a side dish, in salads, on sandwiches or in any number of combinations. Experiment, use your imagination and enjoy!
Michael O’Brien studied biochemistry at Colorado State University. Previously an electrical engineer, he now operates a “dryland” landscaping company and also enjoys organic gardening. His goal is to understand and promote healthy lifestyles.
The reference list for this article is extensive. If you would like a copy, please send a self-addressed, stamped envelope to “Fermented Foods,” Herbs for Health, 1503 SW 42nd St., Topeka, KS 66609.