Page 45 - Comprehensive Food Safety

31.03.2020

USING PRESERVATION METHODS TO CONTROL BUGS

As we looked at earlier, in order to grow to dangerous levels bacteria needs time (more than 4
o
o
hours), the right temperature (5 c to 60 c), moisture, the right pH levels (over 4.6), food (such
as poultry, meat, seafood, dairy products) and some (not all) require oxygen.
There are methods of preservation that can be used to control the growth of bacteria by
removing some of the factors that it needs to grow.

Drying:
Bacteria needs moisture to grow. Lowering the water content (water activity) of food by
dehydrating it will help to stop their growth.

Pickling/acidity:
Bacteria cannot grow or grows very slowly in acidic environments with a pH level of 4.6 of less.

Adding acidic ingredients to a recipe can inhibit the grown of bacteria by lowering the pH level.
For example, adding a vinegar solution to sushi rice, or pickling vegetables.

Canning:

A process of preserving, where food is heated to very high temperatures to kill the bacteria,
and then is placed into sterile cans which then enables the food inside the can to be stored for
long periods.

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