Fermentation is the process by which is food is transformed with the use of yeast, bacteria, and other microorganisms. Fermentation helps to preserve food and make their nutrients more bioavailable. Human beings have been using the benefits of fermented foods for centuries. Be it kimchi in Korea, Sauerkraut in Germany, or kefir in the Middle East, fermented foods are a part of people’s diet all over the world. The past few years have seen a significant rise in the popularity of fermented foods in the US also.
In this article, you will read about some of the best and most popular fermented foods and the various health benefits that they offer.
Yogurt is one of the most consumed fermented food products in the United States. It is made from milk fermented by lactic acid bacteria and bifidobacteria (1). Yogurt is a rich source of nutrients like calcium, phosphorus, potassium, vitamin B12, and riboflavin (2). Yogurt provides many health benefits, including improved digestion, blood pressure regulation, improved bone mineral density, and weight loss (3, 4, 5).
Studies show that prebiotic yogurt can prevent diarrhea in children on antibiotics (6). It also helps reduce the symptoms of Irritable Bowel Syndrome (7). Yogurt is also suitable for people with lactose intolerance as the bacteria in yogurt turn lactose into lactic acid.
Not all varieties of yogurt contain probiotic bacteria; in some yogurts, they are killed during processing. Read the labels carefully to ensure that you are buying probiotic yogurt.
Kefir is a fermented drink made from cow, goat, or sheep’s milk. It tastes similar to yogurt but has a thinner consistency. It is made by adding kefir grains (a combination of yeast and bacteria that look like cauliflower) to milk, which makes it a potent probiotic (8). The kefir grains originated in the Caucasus Mountains. The word ‘kefir’ comes from the Turkish word ‘Keyif,’ which means ‘good feeling’ (9).
Kefir is rich in proteins, which makes it an excellent protein source for vegetarians. It also provides high levels of calcium, magnesium, vitamin B2, vitamin B12, biotin, folate, enzymes, and probiotics. Kefir helps to improve bone health, digestion, and boosts immunity (10, 11, 12).
Regular consumption of kefir helps with the control of plasma glucose, anti-hypertensive effects, and hypocholesterolemic effect (13). Like yogurt, kefir is well-tolerated by people who have lactose intolerance.
Tempeh is a traditional Indonesian food product made from fermented soybean. Once the soybeans have been fermented, they are pressed into a compact cake, which is commonly used as a vegetarian source of protein.
Soybeans are rich in phytic acid, which can impair the absorption of minerals like iron and zinc. Fermentation lowers the amount of phytic acid, and this helps improve the absorption of various minerals (14).
Tempeh has a nutty taste and a firm texture. It can be sautéed, steamed, baked or grilled, and used as a substitute for meat in dishes. It is a rich source of manganese, copper, phosphorus, magnesium, riboflavin, iron, calcium, and potassium (15).
According to a 2016 study, fermenting soybeans helps to release beneficial bioactive peptides. These peptides exhibit several bioactive properties, including anti-hypertensive, antimicrobial, antioxidant, anti-diabetic, and anticancer activities (16).
Kombucha is a slightly fizzy, sour fermented drink made from black or green tea and sugar. The bacteria and yeast used to ferment this tea convert the sugar into ethanol and acetic acid, which give kombucha its unique flavor.
Kombucha contains many species of lactic acid bacteria, which may provide probiotic benefits. Though there is little scientific evidence of probiotic benefits of kombucha, probiotics are known to improve digestion, reduce inflammation, and help in weight loss.
According to a 2003 study on rats, kombucha tea has potent antioxidant and immunomodulating properties (17). Another study showed that kombucha could prevent liver toxicity and damage caused by exposure to harmful chemicals (18).
A lab-based study has also shown that kombucha can decrease the survival rate of prostate cancer cells and thus may be useful in prostate cancer treatment (20). Since most of the studies on kombucha are animal-based or test tube studies, more studies are needed to study its effects on humans.
Saurkraut (sour cabbage) is a finely shredded cabbage that is fermented by lactic acid bacteria. It is made by pressing down shredded fresh cabbage and salt, which releases water and causes fermentation. It is low in calories but is rich in dietary fiber, vitamin C, vitamin K, vitamin B6, sodium, iron, and manganese (21).
Sauerkraut is also high in antioxidants like lutein and zeaxanthin, which help to protect the eyes from damage (22). One small study also found that eating sauerkraut can help reduce the symptoms of irritable bowel syndrome (23).
The high vitamin content in sauerkraut helps to support the immune system, bolster bone and heart health, and reduce inflammation. Studies also show that fermented foods like sauerkraut can also help improve mental health (24). However, not all sauerkraut is fermented. Read the labels correctly before you buy sauerkraut to gain the health benefits of fermentation.
Kimchi is a traditional Korean dish that is made from fermented vegetables like napa cabbage and Korean radish, garlic, ginger, spring onions, chili powder, and salted seafood. It is rich in several nutrients, including vitamin K, vitamin C, vitamin B6, folate, iron, niacin, and riboflavin (25).
The lactobacillus bacterium in kimchi can help boost the immune function (26). The active compounds in kimchi also help in lowering inflammation (27), which helps in reducing the risk of heart disease. According to a 2011 study, kimchi can also help in weight loss (28).
7. Raw cheese
Raw cheese is a fermented and cultured cheese made with raw dairy. Raw dairy already contains beneficial bacteria. When this milk is cultured, it heightens their probiotics levels and also the benefits. Raw cheese is abundant in beneficial bacteria and enzymes, which aid digestion. There are some concerns about the risk of food-borne illnesses from the consumption of raw milk cheese.
Miso is a vital ingredient in Japanese cooking. It is made by fermenting soybeans with salt and koji, a type of fungus. It has a salty, tangy, and a strong umami flavor. The miso paste is used to make miso soup, which is a popular breakfast in Japan. This high protein paste is also rich in various B vitamins, vitamin E, K, and folic acid. It also contains copper, manganese, and zinc.
The powerful probiotics in miso help combat digestive issues like constipation, diarrhea, gas, bloating, and irritable bowel syndrome. Although it is high in sodium, miso does not lead to an increase in blood pressure. Miso also helps prevent radiation injury and slows the progress of cancerous tumors (29). Another study showed that eating miso soup for three months can lower harmful cholesterol levels significantly (30).
Natto is a traditional Japanese dish made from fermented soybeans. It has a slimy texture and a pungent odor. It is made by soaking soybeans and then boiling them. Bacillus subtilis bacteria are added, and then this mixture is allowed to ferment over time.
It is rich in proteins and vitamin K2, which is essential for forming, strengthening, and repairing bones and teeth (31). According to a 2012 study, habitual intake of natto has a beneficial effect on the bone health of older men (32). The fermentation of natto also produces an enzyme known as nattokinase. According to a study that involved 12 men, supplementing with nattokinase can prevent and dissolve blood clots (33). Another study shows that nattokinase also helps prevent and treat hypertension (34).
Apple cider vinegar (ACV) is a vinegar made from fermented apple juice. The organic and unfiltered apple cider vinegar contains ‘mother,’ which are strands of proteins, enzymes, and friendly bacteria that give it beneficial properties.
Certain acids like acetic acid present in apple cider vinegar also support the function of probiotics in the gut. Apple cider vinegar offers numerous health benefits, including weight loss, improved heart health, lower cholesterol levels.
Fermented pickles or brined pickles undergo curing for several weeks in which the fermentative bacteria produce acids necessary for the preservation process. These pickles contain vitamins, minerals, and antioxidants in addition to probiotic bacteria.
Pickles are a good source of vitamin K, which is crucial for several processes like blood clotting, calcium absorption, and keeping calcium out of the arteries. The probiotics available in fermented pickles help to strengthen the gut and the immune system.
Fermented pickles help in weight loss, improve mental health, improve skin health, and can also lower the risk of Parkinson’s disease. Studies show that a diet rich in probiotics can help prevent colorectal cancer (35). However, not all pickles are fermented. Most store-bought pickles are made with vinegar and do not go through the fermentation process. When choosing a jar of pickles, look for the words lactic acid fermented pickles on the label.
Kvass is a fermented drink made from black or regular rye bread. It is considered a non-alcoholic beverage as it contains less than 1.2 percent alcohol. The taste of kvass is similar to that of beer. Kvass contains a variety of nutrients, including vitamin B12, selenium, manganese, and folate.
It is rich in probiotics, which help improve the health of the intestinal tract and boosts the immune system. The high dose of antioxidants in kvass can reduce inflammation in the liver and prevent liver disease. Beet kvass also helps to treat chronic fatigue syndrome, chemical sensitivities, and allergies.
13. Sourdough bread
Sourdough bread is made with a live fermented culture of flour and water, which acts as a natural leavening agent. The flavor of sourdough can range from mild to strong. It has a chewy texture and crisp crust. Sourdough bread is rich in several nutrients such as iron, selenium, and many B vitamins.
The presence of bacteria in sourdough due to its unique fermentation process allows better nutrient absorption and improves gut health. Some studies also show that fermentation alters the structure of carbs in the dough for improved blood sugar control and low glycemic index score.
14. Traditional buttermilk
Traditional buttermilk is the liquid leftover from making butter. Consumed mainly in India, Pakistan, and Nepal, this buttermilk contains probiotics. It is low in calories and fat and rich in calcium, phosphorus, riboflavin, and vitamin B12.
The lactic acid in buttermilk makes it easy to digest. Buttermilk is also rich in calcium, phosphorus, vitamin D, and vitamin K2, which helps in maintaining bone strength and preventing osteoporosis (36). Fermented buttermilk also has anti-inflammatory effects on the skin cells that line your mouth (37).
While fermented foods provide many health benefits, having too much can lead to digestive issues like bloating and diarrhea. Introduce fermented foods to your diet slowly and work your way up. To achieve the maximum benefits, buy foods that are organic and contain live and active cultures. Look for products that do not include a lot of sugar or additives.
Fermentation has been used for centuries to increase the shelf life of many foods. This process also boosts the health benefits of food products. The health benefits of these foods include improving digestion, raising immunity, improving bone mineral density, fighting allergies, and lowering inflammation.