Lactic acid bacteria is a collective term for a group of Gram-positive bacteria with different morphology, metabolic properties and physiological characteristics. There are more than 40 species of lactic acid bacteria found so far. They feed on carbohydrates, which they break down to produce lactic acid. Many lactic acid bacteria are recognized as safe food-grade microorganisms. They have a variety of probiotic functions, can maintain the balance of the human micro-ecological system, reduce blood lipids, blood pressure, suppress cancer, control endotoxins in the body, enhance immunity, and inhibit the growth and reproduction of bacteria in the intestinal tract , Regulating the normal flora of the gastrointestinal tract of the body.
- 一. Application of lactic acid bacteria in dairy product processing
Dairy products include yogurt, cream, cheese, active lactic acid bacteria drinks, lactic acid bacteria milk powder, lactic acid bacteria fermented custard, alcoholic fermented milk drinks, etc. Has reached more than 1000 kinds. The technology of fermenting dairy products with lactic acid bacteria is very mature, which can not only improve the nutritional value, but also produce lactic acid, decompose protein, form flavor substances, and produce antibacterial substances. At present, dairy products have become an important food composition.
- 二. Application of lactic acid bacteria in the production of vegetable protein fermented milk
Soybeans, peanuts, walnuts, almonds or melon seeds are soaked and sterilized, then ground, mixed with milk, and fermented by lactic acid bacteria to produce pure natural vegetable protein fermented milk with good coagulation state, excellent color and fragrance, and does not contain any preservatives. These fermented milks have high protein content and are easy to absorb, and are fermented products with great potential development capabilities. Lactobacillus acidophilus, Lactobacillus bulgaricus, Streptococcus thermophilus, Lactobacillus delbrueckii, Lactobacillus plantarum, Leuconostoc enterococci, Streptococcus soymilk, etc. are commonly used in production, and two or more strains are commonly used for mixed fermentation .
Application of lactic acid bacteria in the processing of fruit and vegetable products and grain products
- Fermented fruit and vegetable products
Fruit and vegetable fermentation is a way of deep processing of fruits and vegetables by using the activities of beneficial microorganisms and controlling certain growth conditions. Lactic acid bacteria fermented fruits and vegetables fully meet the needs of the above-mentioned people. The most common application is the production of kimchi and sauerkraut by lactic acid bacteria. After the fruits and vegetables are fermented by lactic acid bacteria, the nutritional value of the products is improved, the flavor is improved, the shelf life is extended, and the health care function is increased at the same time.
1) Fermented vegetables
Kimchi and sauerkraut have a long history in China and are deeply loved by the masses. The traditional method is to rely on the natural fermentation of lactic acid bacteria carried by the vegetables themselves. The process is as follows: wash the vegetables and put them in a specific container, add various ingredients, complex biochemical reactions occur in a special environment, lactic acid makes the finished product have a sour taste, esters make the finished product have a fragrance, and amino acids make the finished product have a umami taste. Although kimchi, sauerkraut raw materials are different. But the common lactic acid bacteria are Lactobacillus brevis, Lactobacillus, Lactobacillus cucumber and Bifidobacterium. Artificial inoculation of lactic acid bacteria is often used in modern industrial production. Compared with traditional natural fermentation, modern industrial production has more advantages, the fermentation cycle is shorter, and the quality and safety of products are more guaranteed.
2) Fruit and vegetable lactic acid bacteria drink
Fruit and vegetable lactic acid bacteria drink is made by using lactic acid bacteria to ferment single or compound fresh fruit and vegetable juice, adding a small amount of milk powder and lactose used by lactic acid bacteria to make a fermented vegetable juice drink, which has both the frankincense of yogurt and rich vitamins and inorganic salts. Nutritious ingredients, pleasant taste.
It can be seen that lactic acid bacteria play a very important role in the food industry.