Piimhappekäärimise

Piimhappekäärimine is the Estonian term for lactic acid fermentation. This is a metabolic process that converts sugars such as glucose, lactose, and fructose into lactic acid. This process occurs in muscle cells during strenuous exercise, when oxygen supply is insufficient for aerobic respiration, and also in certain bacteria and yeasts.

In the context of food production, lactic acid fermentation is a crucial process. It is responsible for the characteristic tangy flavor and preservative qualities of many fermented dairy products, including yogurt, kefir, sour cream, and various types of cheese. Bacteria, primarily from the Lactobacillus and Streptococcus genera, are responsible for this transformation. They consume lactose, the sugar found in milk, and produce lactic acid as a byproduct. This acid lowers the pH of the milk, causing the proteins to denature and coagulate, resulting in the thickened texture of these products.

Beyond dairy, lactic acid fermentation also plays a role in the production of other fermented foods like sauerkraut (fermented cabbage), kimchi (fermented Korean vegetables), and sourdough bread. In these cases, lactic acid bacteria ferment the carbohydrates present in the plant materials, contributing to their preservation and unique flavor profiles. The process not only preserves food by creating an acidic environment that inhibits spoilage microorganisms but also enhances digestibility and can increase the nutritional value of the food by producing certain vitamins.