Temperature is the most important tool for keeping food safe. Bacteria grow slowly in the cold, quickly at room temperature and die at high heat. The law has few fixed figures, but the Swedish Food Agency's guidance and industry guidelines give guide values that most businesses use. The basic requirement is in Annex II, chapter IX of Regulation (EC) No 852/2004: food must not be stored or handled at a temperature that could cause a health hazard.
Cold storage
- The Swedish Food Agency's guidance says that the risk of bacterial growth increases substantially above +8 °C. A common guide value for chilled goods is therefore no more than +8 °C, but colder is better.
- Many goods have a storage instruction on the packaging, for example no more than +4 °C. It must be followed, and that figure takes precedence over the general guide value.
- Have working thermometers in fridges and also measure the temperature of goods when they are delivered. Put chilled goods in the fridge straight away when they arrive.
- It can be colder in some parts of the fridge than in others. Learn where it is coldest.
- If the fridge has been too warm, someone must assess whether the food is still safe. Ask your manager. Do not use the food on your own.
Freezer storage and thawing
- Frozen goods are stored at -18 °C or colder, or the temperature the packaging states.
- Freezing does not kill all bacteria. Some survive and can grow when the food thaws.
- Preferably thaw in a fridge (no more than +8 °C) or in a thawing cabinet. There is no explicit requirement for this, but time and temperature must be under control.
- Quick thawing at room temperature or in cold water (with the goods tightly packed) can work, but only if the business has control of time and temperature.
- Thaw water from meat and fish must be drained away so that it does not contaminate other food.
Cooking
The law has few detailed requirements. In its guidance the Swedish Food Agency recommends about 70 °C at the core, for example for hamburgers. Harmful bacteria then normally die quickly. Remember:
- Measure at the core, in the middle of the thickest part, with a clean thermometer.
- Colour is not reliable. Mince that has been packed in a protective atmosphere can look done as early as 55 °C, and in rare cases mince can look pink even though it has reached over 70 °C.
- Minced beef and lamb must be cooked through properly, because bacteria from the surface are found throughout the mince. A whole piece of meat is less sensitive, because the bacteria are mainly on the surface.
Hot holding
- The Swedish Food Agency recommends at least +60 °C as a guide value. That gives a margin to the temperatures where some bacteria start to grow, around 50 to 55 °C.
- If the whole dish stays at 55 °C or more the whole time, hot holding poses no health risk. Measure the temperature at the surface, because the food cools there first.
- Longer hot holding reduces taste, appearance and vitamins.
Cooling down
- Cooked food that is to be served cold or kept must be cooled down as quickly as possible.
- The Swedish Food Agency's guide value is that cooling down, for example from 60 °C to 8 °C, may take no more than six hours. If it takes longer, a risk assessment must be made before the food is served.
- Speed up cooling by dividing the food into shallow containers, spreading it out or using an ice-water bath. Cooling in water is about seven times faster than in air.
- Measure the core temperature, because the core cools last.
- Do not put a large hot pot straight into a full fridge. It can warm the other goods.
Reheating
According to the Swedish Food Agency, cooled food that is to be hot-held should be heated to 70 °C or more, and as quickly as possible. Most disease-causing bacteria then die quickly. Ready-to-eat food such as hot-smoked fish or chilled pies does not need to be heated that high if it has been cooled, stored and handled correctly.
Thermometers and logging
The business must have working thermometers and should check them at regular intervals. Many businesses record temperatures in a log. That is part of the self-checks.