The fact is well-known that milk under goes a number of chemical changes in its constituents some hours after milking. It becomes sour, owing to the decomposition of the milk sugar, the case in separates, and finally putrefactive decomposition begins.
These changes are induced by the presence in milk of bacteria, which for the most part do not generate diseases, but which maybe, and often are, accompanied by bacteria capable of causing disease that obtain access to the milk from the body of the animal, from the air, from the water that was used to wash the cans, from the hands, clothing, and person of the milker, and the like.
Sterilization of milk is made to obtain a safe product from sanitary-and-hygienic point of view and to provide its long storage at an ambient temperature without the change in quality. Sterilization is the killing or removal of all microorganisms, including bacterial spores which are highly resistant. Sterilization is an absolute term, i.e. the article must be sterile meaning the absence of all microorganisms.
It is the process of heating to a high enough temperature (usually more than 100°C) for specific time to kill almost all bacteria. The sterilized milk can be stored at room temperature for a long period of time. The sterilization of milk has the following characteristics.
•Temperature more than 100°C is used in the process.
•No chilling is required for storage. Excellent storage life at room temperature.
•High operating pressure is employed to prevent milk from boiling at the processing temperature.
Long storage life and the possibility of storage at usual temperature modes allow transporting this production to distant regions. Consumers are attracted by the guaranteed product quality and the possibility to use it while traveling.
Sterilization of milk
