Raw milk from a farm was found to contain 3 104
bacterial cells per millilitre when analysed at
the dairy. Before being packaged, the milk is pasteurised so that the milk contains not more than
10 cells per millilitre.
1.1 What is the minimum time the milk has to be heated if the D63 value is 8 minutes?
"thermal death rate" or the apparent heat resist- ance was the "D value," which is defined as the. time, in minutes, to reduce the population by 90% at a constant, lethal temperature.