PASTEURIZATION


 Louis Pasteur discovered a technique of heating food just enough to process it without altering its composition. This process is termed as pasteurization. 



It is a mild heating of process used to destroy spoilage organisms, without altering the composition of product. 

By this process, non-spore forming pathogenic bacteria like mycobacteria, Salmonella, etc are destroyed.

Pasteurization is done in 3 ways:
  • High Temperature Short Time method (HTST)
  • Low Temperature Holding method (LTH)
  • Ultra High Temperature (UHT)

High Temperature Short Time method (HTST)

For this method, milk is heated to 72 degree Celsius for 15-20 secs followed by sudden cooling to 13 degree Celsius. By doing this, pathogenic bacteria are killed.

Low Temperature Holding method (LTH)

The same result is achieved when milk is heated to 62 degree Celsius for 30 mins followed by sudden cooling to 13 degree Celsius.

Ultra High Temperature (UHT)

Here milk and milk products are heated at 140 -150 degree Celsius for 1-2 secs. UHT processed milk does not require refrigeration and can be stored for 2 months without flavour change.

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