Fermentation is the process of using microorganisms, such as bacteria or yeast, to convert carbohydrates to alcohol or organic acids under anaerobic conditions.

There’s two types of fermentation: alcoholic and lactic acid.

Alcoholic fermentation, or ethanol fermentation, is where pyruvate (from glucose metabolism) is broken down into carbon dioxide and ethanol by bacteria and yeast. Alcohol fermentation has been used to produce beer, bread and wine.

Pyruvate molecules from glucose glycolysis may be further fermented into lactic acid. Lactic acid fermentation converts lactose into lactic acid. (1)

There are numerous benefits to fermenting food.

Firstly, fermentation serves to enhance the digestion of food. Your body needs adequate digestive enzymes to properly absorb, digest, and utilise nutrients in food. When vegetables like cabbage and cucumbers are left to steep and sit until the sugars are broken down to promote the growth of bacteria, this is when the vegetables are fermented.

Fermented foods are also filled with beneficial bacteria that work as reinforcements for the good bacteria in the digestive system. Since 70 to 80 percent of the immune system lies in the gut, having proper balance of gut flora is important.

Fermentation and Probiotics

In the late 19th century, microbiologists realised micro-organisms in the gastrointestinal tract of healthy individuals were different than those who were sick. These beneficial microflora were named probiotics, literally meaning “for life.” Probiotics are micro-organisms proven to exert health-promoting influences in humans and animals. The reason why fermented foods and drinks are beneficial is because of the natural probiotics they contain.

According to the Journal of Applied Microbology, the benefits of consuming probiotics include “(i) improving intestinal tract health; (ii) enhancing the immune system, synthesizing and enhancing the bioavailability of nutrients; (iii) reducing symptoms of lactose intolerance, decreasing the prevalence of allergy in susceptible individuals; and (iv) reducing risk of certain cancers.” (3)

Probiotic bacteria not only balance the good bacteria in the gut, but they also help to “tune up” the immune system. As high as 70 percent of the immune system lies in the intestine, so nurturing the bowel immunity with probiotic bacteria keeps the intestinal tract healthy. Some probiotic-rich foods include fermented cheese and soy sauce, kimchi, and sauerkraut. Just as there are fermented foods, you can nurture your intestines with fermented probiotic beverages like kefir and kombucha.