Pasteurization Of Milk - Thermal Lethality Determinations

Require the applications of microbiology to appropriate processing determinations.

To ensure destruction of all pathogenic microorganisms, time and temperature combinations of the pasteurization process are highly regulated

Ontario Pasteurization Regulations

Milk:

* 63° C for not less than 30 min.,

* 72° C for not less than 16 sec.,

or equivalent destruction of pathogens and the enzyme phosphatase as permitted by Ontario Provincial Government authorities. Milk is deemed pasteurized if it tests negative for alkaline phosphatase.

Frozen dairy dessert mix (ice cream or ice milk, egg nog):

at least 69° C for not less than 30 min;

at least 80° C for not less than 25 sec;

other time temperature combinations must be approved (e.g. 83° C/16 sec).

Milk based products- with 10% mf or higher, or added sugar (cream, chocolate milk, etc)

66° C/30 min, 75° C/16 sec

There has also been some progress with low temperature pasteurization methods using membrane processing technology.