Classic kefir is a symbiosis of yeast (a type of fungus) and bacteria. The structure that grows, similar to a cauliflower, is a matrix made up of polysaccharides (sugars), fats and protein, which some species of bacteria make to protect themselves. They help in case of diarrhea. Reduce allergies. They produce vitamins, A, B, and K. They enhance the absorption of calcium, iron, copper, zinc, magnesium and manganese. They help in case of constipation, regulating peristaltic movements, with a proper diet. They slow down the progression of serious liver problems. They balance the intestinal flora. They favor the biodegradation of lipoproteins. They increase the good lipoproteins (HDL). They eliminate toxins from the body. They activate the functions of the immune system. It is recommended to use fresh or UHT cow, goat, or sheep milk to ferment, with fresh and goat milk being the healthiest. It also ferments vegetable beverages, especially some brands of almond, coconut, soy, and oat beverages. The soy drink curdles perfectly and produces a high-quality, excellent-tasting kefir. The other vegetable drinks give rise to a liquid kefir, although they can be thickened by mixing them with soy drink, guar gum, arrowroot, tapioca starch or agaranta. It is suitable for vegans and lactose intolerant people, because despite containing slight traces of dairy due to the medium in which it has been grown, when the fermentation of a vegetable drink begins, the bacteria itself first consumes these small remaining traces, eliminating them completely. Keep the envelope cold and better use it completely once opened, to prevent moisture from entering, bacteria being activated and dying due to lack of food, or contamination by pathogens. If you want to reserve a part of the envelope, fold it very well, press it with a clip and put it in a closed bag in the refrigerator, without taking more than a week to spend it all.