Temperature Control

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Temperature Control

It's really important to store food in conditions that bacteria won't grow and multiply in. You need to bear certain temperatures in mind when handling food.

Danger zone: 5-63°C

Between 5°C and 63°C, bacteria can grow and multiply very rapidly.
Bacteria grow best at 37°C, which is normal human body temperature.
Hot food should be eaten before it drops below 63°C.

Chilling: 0-5°C

Food may harden a little when it's chilled, but besides that, food doesn't really change when it's chilled.
Storing food between 0°C and 5°C will slow bacteria growth and increase shelf life (how long the food stays safe for).

Freezing: -18°C

Bacteria can no longer grow at temperatures below -18°C.
Freezing preserves nutrients and increase the shelf life of many foods.
It's important to note that bacteria become dormant when food is frozen - they don't die. As soon as food defrosts, they turn active again.

Cooking or reheating: 75°C

To destroy bacteria, we should cook food at temperatures higher than 75°C.
We should only reheat food once, and we should always reheat food thoroughly. We should heat the food for a minimum of 3 minutes or until the food is 'piping hot' (definitely above 75°C).

Correct Use of Fridges and Freezers

Fridges and freezers need to be set to certain temperatures. You must store food correctly in fridges and freezers to avoid contamination and disrupting the circulation of air.

Fridges

The temperature of a fridge should be set at 0-5°C.
To prevent food contamination, foods should be put into containers or covered.
Store raw meats, fish and poultry at the bottom of the fridge to prevent blood and juices from leaking onto other foods.
Putting too much food in fridges will disrupt air circulation and therefore the removal of heat from food.

Freezers

The approximate temperature of a freezer should be -18°C.
You should note on food packaging when you stored the foods.
When you take foods like poultry and meat out of the freezer, you should place them in the fridge to allow them to defrost properly.
You may have to adjust cooking times for food that's been left to defrost - if parts of the food are still frozen, you'll need to cook the food for longer to destroy all of the bacteria.
Food packaging will often include a 'cook from frozen' guideline. You should follow this if cooking directly from frozen.

Star ratings

Star ratings - tell you how long you can store foods in fridges and freezers for.
For example, in a fridge's freezer compartment you should store:
- 1★ foods - maximum 1 week at around -6°C.
- 2★ foods - maximum 1 month at around -12°C.
In a freezer, you should store:
- 3★ foods - up to 3 months at around -18°C.
- 4★ foods - no longer than the 'best before' date at -18°C or below.

Fridge layout

Top shelves and middle shelf: ready-to-eat foods (e.g. sandwiches, yoghurts, cured meats, condiments etc.)
Bottom shelves: raw meat, fish, poultry.
Salad drawer: fruit, vegetables and salad vegetables.