Make yogurt lactic acid bacteria medium high prize .

1. Instruments and materials used in making yogurt.

Sterilization equipment, fermentation tanks or fermentation chambers, heating tanks, ultraviolet lamps, glass or porcelain bottles or special paper basins, fresh milk, sugar, lactic acid bacteria (Bulgaria bacillus and Streptococcus thermophilus), etc.

Second, the production steps.

1. Disinfection and sterilization of glass bottles. The glass bottle is sterilized in the sterilizer for half an hour, if it is sterilized in a steamer, it takes 45 minutes, the inoculation room needs to be sterilized by ultraviolet light for 50 minutes, and the inoculation tool is sterilized in an autoclave for 30 minutes.

2 Milk sterilization. Put fresh milk into a heating tank, add 10-12% sugar, and sterilize at 85-90 for 30 minutes or by other methods. Whichever method is used, it is better not to destroy the original nutrients of the milk, and it is cooled after sterilization.

It is best to remove the upper layer of grease before or during sterilization to defatease the milk.

3 Vaccination. The sterilized milk with a temperature lower than 43 is divided into sterilized glass bottles, inoculated in the inoculation room according to the inoculation amount of 2%-4% of the milk and stirred evenly, paying attention to the canning to be full, leaving no gaps, and sealing immediately after connecting to ensure the anaerobic conditions of lactic acid fermentation. Then it is sent to the refrigerated chamber of 0-5 for refrigeration and then cooked for 8 to 10 hours.

You can get some bacteria, and then put them in a clean box, crisper box, pour in pure milk foam, and the bacteria will grow slowly.

The process of making a lactic acid bacteria drink at home:

1. Prepare 8 bags of whole fresh milk and two lemons, squeeze out the lemon juice, pour the milk into the pot and boil, pour the lemon juice into the pot in three times, 2. As shown in the figure below, heat the milk while stirring until a large amount of flocculent matter appears in the milk, separate the transparent liquid, and turn off the heat.

3. Pour the milk into the bowl with two layers of gauze pads, hold the gauze tightly and lift it tightly to separate the solid and liquid, and the solid after draining the water is cream cheese, which can be kept to make cheesecake.

4. What needs to be used here is the isolated whey, prepare a bottle of Yakult, a little honey, half a lemon, and milk can be added according to personal taste.

5. Pour the whey into the cup, add the milk, add the Yakult, add the honey, put the lemon slices into the cup, and leave a slice for decoration.

Lactic acid bacteria are inseparable from lactic acid, and they are bacteria that produce lactic acid when using carbohydrates such as glucose. It is not taxonomic.

on a class of bacteria. Lactic acid bacteria also have a common feature, that is, they can grow under both aerobic and anaerobic conditions, that is, they are mostly facultative anaerobes.

Lactic acid bacteria include various lactobacilli, lactococcus, streptococcus, enterococci, bifidobacteria, etc., which are closely related to humans. On the one hand, bifidobacteria and lactobacter are the most important beneficial bacteria in the human intestine, which play an important role in human nutrition, immunity, health care and even aging and longevity. On the other hand, many lactic acid bacteria such as streptococcus and enterococci can sometimes be harmful to the human body, causing diseases or producing toxins. In addition, lactic acid bacteria are also widely used in dairy processing, and many unique flavor and mouth-watering dairy products, such as yogurt, cheese, and cream, require lactic acid bacteria.

Of course, various microecological preparations with lactic acid bacteria as the main production strains are inseparable.

MRS medium is the most commonly used medium for lactic acid bacteria.

1. Formula: 100 ml of water, 1 gram of beef paste, 1 gram of peptone, 1 gram of yeast paste, 20 grams of tomato juice, 1 gram of glucose, 1 gram of Tween, gram of calcium carbonate, 1 to 2 grams of bromocresol green, 1 to 2 grams of agar. Reputational disturbance.

2. Preparation method: take an appropriate amount of water in a pot according to the proportion and heat it. Weigh the medicine and add it to the water in turn, without agar. After the medicine in the pot boils, pour it into an Erlenmeyer flask with agar, stopper and bandage. Sterilize at 120 degrees Celsius for 20min.

3. Other precautions: After the medium is sterilized, it must be incubated in a 37 degree Celsius incubator for 24 hours, and the sterile can only be used by the elderly. The medium can also be made into an agar free liquid medium for the cultivation of fungi.

Peptone is easily deliquescent and needs to be weighed quickly. Tomato juice is made by pressing fresh tomatoes.

MRS medium is the most commonly used medium for lactic acid bacteria.

1. Formula: 100 ml of water, 1 gram of beef paste, 1 gram of peptone, 1 gram of yeast paste, 20 grams of tomato juice, 1 gram of glucose, 1 milliliter of Tween, 1 gram of calcium carbonate, 1 gram of bromocresol green, 1 to 2 grams of agar.

2. Preparation method: Take an appropriate amount of water in a pot according to the required amount according to the proportion and heat it. Weigh the medicine and add it to the water in turn, without agar. After the medicine in the pot boils, pour it into an Erlenmeyer flask with agar, stopper and bandage. Sterilize at 120 degrees Celsius for 20min.

3. Other precautions: After the medium is sterilized, it must be placed in the empty draft 37 degrees Celsius incubator for 24 hours before it can be used by aseptic growth. The medium can also be made into a liquid medium without disturbance agar when used, which is used for the cultivation of fungi.

Peptone is easily deliquescent and needs to be weighed quickly. Tomato juice is made by pressing fresh tomatoes.

The process of making lactic acid and antibacterial bacteria is basically the same:

1. The raw material dissolving tank dissolves the raw materials, and dissolves the milk powder and sugar into liquid milk raw material liquid with hot water.

2. Filtration, filter out the powder that has not yet been dissolved in the raw material to avoid blocking the pipeline of raw material transportation.

3. Hydraulic sterilizer sterilization, the filtered raw material liquid is transported through the hydraulic sterilizer for pasteurization.

4. Make the fermentation broth, and send the pure lactic acid bacteria and raw material liquid in the fungus argument tank into the culture tank for fermentation for a few days.

5. Homogenizer homogenization, because after a few days of fermentation, it will cause the substances in the fermentation broth to precipitate and stratify, so it is necessary to homogenize the fermentation broth to avoid precipitation.

6. Cooler cooling, cooling the fermentation broth.

7. Liquid blending, the syrup and fermentation liquid in the syrup tank are transported into the blending liquid storage tank for uniform blending. After the above 7 steps, the concentrated solution of the lactic acid bacteria milk drink is ready.

When cultivating this rubber fungus, vitamins need to be added. According to the Qingxia Education Network, vitamins need to be added to the medium when cultivating lactic acid bacteria, and the addition of combined vitamins can improve the activity of lactic acid bacteria, and the metabolic flux is conducive to lactic acid generation when the same bond is carried, which can promote the growth of lactobacilli and reduce the mortality rate of bacteria.

In addition, lactic acid bacteria cannot independently synthesize auxotrophic strain, which is necessary for growth and reproduction, and cannot be synthesized in the body, so additional growth factors need to be added, so Liang Liangjin vitamins should be added to the medium for cultivating lactic acid bacteria.

It should be noted that artificially cultivated microorganisms must not only have the appropriate ratio of nutrients, but also provide appropriate environmental conditions.