The pasteurization technology is named after the French microbiologist Louis Pasteur, who lived in the late nineteenth century. Its essence is a one-time heating of products of liquid consistency, which leads to disinfection from various microorganisms. This allowed to increase the shelf life of products. Originally
the technology was for beer and wine.
This method of conservation was widely used in the processing of dairy products. Pasteurization of milk is the process of heating to a temperature close to boiling, and the destruction of pathogens without changing the basic properties - smell, texture and taste.
The main task of pasteurization of milk is to prevent its premature acidification caused by lactic acid bacteria, as well as the multiplication of E. coli and other microorganisms.
In
industrial production, a phosphatase reaction is used to control the effectiveness of pasteurization. With a negative reaction, it is believed that all non-spore-forming
pathogenic bacteria died. The efficiency of the process will be high only if, immediately after milking, the milk was cooled to a certain temperature and stored with it until pasteurization. For this purpose, special cooling tanks are used on livestock farms.
In practice, pasteurization of milk can be carried out in three different ways.
Long pasteurization - the milk is heated to a temperature of 65 degrees and maintained in this state for half an hour.
Short-term pasteurization - heating occurs up to 75 degrees and after twenty seconds, processing stops.
Instant pasteurization of milk - this is heating it to a temperature of 85 degrees - and immediately cooling. If pasteurization of milk was done instantly, the physical and chemical properties of some elements change, due to which its taste is changed.
Milk production equipment is used only on an industrial scale. At home, pasteurization can be done using a double boiler. First you need to sterilize the container in which the milk will be stored by placing
her in an ordinary oven at a temperature of about one hundred degrees for about twenty minutes. Or you can do this by traditional methods using steam.
Next, milk is poured into the upper chamber of the double boiler and the thermometer is placed so that it does not touch the walls, and water in the lower chamber. The milk is brought to a temperature of 65 degrees and is constantly stirred for thirty minutes. It is important to ensure that the temperature does not rise.
If the milk is heated to 75 degrees, then pasteurization should be carried out only for fifteen minutes. After that, the container with milk should be immersed in ice water without stopping stirring until the temperature drops to four degrees Celsius.
After that, the milk is poured into a sterilized container, closed with a lid and refrigerated. Within two weeks, you can not worry that it will turn sour.