Fermented milk products and pickled vegatables – are these probiotics?

In recent years, we have observed a trend on the market related to the expansion of organic and natural products. Consumers largely pay attention to products quality. It would seem that “natural probiotics” perfectly fit into this trend. What are “natural probiotics” and how do they work?

What are probiotics and “natural probiotics”?

According to the definition of the United Nations Food and Agriculture Organization (FAO) and the World Health Organization (WHO), probiotics are live microorganisms that have a beneficial effect on the host health when administered in the right amount. Probiotics are microorganisms isolated from the gastrointestinal tract of a healthy person with a confirmed activity profile and safety. Probiotic microorganisms must be resistant to the acidic pH of gastric juice, bile salts and digestive enzymes and be able to adhere and colonize the surface of the intestine. The probiotic properties of microorganisms are strictly strain-dependent, i.e. specific to one strain of a given species.

“Natural probiotics” is the term used for fermented milk products (yogurt, kefir, acidophilic milk, kumys) and for fermented vegetables  (sauerkraut, pickled cucumbers), presented as an alternative to commercially available probiotic products (in dry form: tablets, capsules, sachets, and in liquid form: drinks, concentrates and probiotic supplements). However, the term is misleading and incorrect. Fermented dairy products and pickled vegetables are not the same as probiotics.
According to the definition of the International Dairy Federation, fermented milk drinks are products made from whole milk, partly skimmed or completely fat-free, or obtained from reconstituted powdered milk, which have been fermented by specific microorganisms. Pickled vegetables are also produced during the fermentation process involving microorganisms.

Similarly to probiotics, lactic acid bacteria are also in fermented milk products and fermented vegetables, but they are not strictly defined strains. Fermented products are a source of bacteria that support the intestinal microbiota, but we cannot assume that they work in the same way as the strains contained in probiotic preparations, where the composition of microorganisms is selected and strictly defined. Microorganisms from probiotic preparations have confirmed and documented activity in the prevention and treatment of various body dysfunctions (maintaining the microbiological balance of the intestines after antibiotic therapy, regulating the digestive tract, strengthening the immune system and maintaining the psychophysical balance of the body) while bacteria present in fermented products are “accidental”. It makes it impossible to attribute a specific beneficial effect on our body.

Fermentation is one of the methods of food preservation, used to extend its shelf life and it allows to make products with specific organoleptic qualities. Fermented products have also high nutritional value. Bacteria  broke down carbohydrates into lactic acid, which is why fermented products are  lean. Fermented dairy products are a very good source of B vitamins and calcium, affecting our bones and teeth, and also contain vitamin A as well as phosphorus, potassium, iodine and zinc. Fermented vegetables are a source of vitamins B1, B2, B3, which regulate metabolism and facilitate the digestion of proteins, fats and carbohydrates, smooth the skin, strengthen hair and nails and increase iron absorption, protecting against anemia. The richness of these products means they should be a permanent component of a rational, balanced diet.

A properly balanced diet (the number and quality of meals, hours of eating meals) is the basic factor for good body condition. Consuming the right proportions of all nutrients (proteins, fats, carbohydrates, vitamins, minerals) is very important for the proper functioning of the body. Fermented  products are also very important in the daily diet, however, the lack of strictly defined strains and indefinite number of microorganisms means we cannot call fermented products “natural probiotics”.

Functional food

Functional food is the binder that connects probiotics with food. According to Functional Food Science in Europe (FUFOSE), food can be considered functional if it has been proven to have a beneficial effect on one or more bodily functions beyond the nutritional effect.

This impact is based on improving health and well-being or reducing the risk of disease. Functional foods must resemble conventional food and  have beneficial effects on the body. These are not tablets, capsules or drops, but a part of an proper diet. The production of functional food, including probiotic products, has been gaining public interest in recent years. Functional foods containing probiotic microorganisms prevent such diseases as: irritable bowel syndrome, diarrhea, atopic dermatitis, vaginal infections, hypercholesterolemia, obesity, lactose intolerance and they are also credited with having anti-cancer effects. High-quality products containing probiotics (e.g. yogurts enriched witch specific bacterial strains) have measurable positive effects on our health. It is also worth considering that there are probiotic drinks without milk proteins. It is an interesting alternative for people with allergies and intolerance to dairy products. Probiotic drinks have a strictly defined list of strains and an exact number of each one. Information about the composition and amounts of bacteria guarantee that we deliver to the body recommended daily dose of probiotic bacteria. We are also sure that bacteria are only beneficial to our health.

Choosing the right food, we should consider the description. Products containing probiotic microorganisms should be marked on the label by the generic type name, the species name and the letter and number designation. The minimum number of live probiotic bacteria in the finished product is 10⁶ cfu/g or ml of product. As aware consumers we should be alert to the catchy slogans: “natural, ecological”. Complementary daily diets with fermented products is desirable. However, we should choose a probiotic or functional food containing strictly defined probiotic microorganisms if we want to be sure we support fighting with many specific diseases.

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