Question

how is milk pasteurized
milk is pasteurized in order o kill any kind of harmful microorganisms present in it and to increase its shelf life. pasteurization is a process in which the milk is heated to a certain temperature for a fixed period of time and then is quickly cooled. for example it may be heated at 80° C for 15 minutes and then immediately cooled.this helps to kill any kind of microorganism which is present in milk.​

Answer 1

Answer:

In simple words, pasteurization is the process of heating the product to particulate time - temperature combination & chilling it below refrigeration temp, to render it pathogens free (disease causing orgnism) or to kill bad bacteria & make it safe to eat. Heating will kill pathogens & chilling will stop or reduce growth of other bacteria. Thus, it will help reduce the transmission of diseases, such as typhoid fever, tuberculosis, scarlet fever, polio, and dysentery. It also increase the shelflife to product as it decreased the microbial load to significant amount.

Time - temperature combination used for pasteurization varise from product to product & final requirements of the product.

Different kinds of process are used for pasteurization

HTST - (High temperature short time) product is heated to higher temp. & Short spam of time to achieve the desired result i.e. to kill pathogens

LTLT - ( Low temp. Long time) product is heated to low temp & holding is done to longer time.

Now a days HTST process is widely used in food industry for pasteurizing the products. For example - in case of milk, milk is heated to around 72 degree Celsius & hold to 15 sec to kill the all pathogens in milk & chilled to temp beliw refrigeration

Time temp combination used is decided in way that it kills the most heat resistant bacteria present in the product, that is index organism. Index organism of milk is “coxiella burnetii” this means after heating milk for 72 degree/15 sec coxiella will be killed & milk will be pathogen free & safe to consumption