Freezing and quick-freezing are common preservation methods used to extend the shelf life of food and reduce food waste. Low temperatures inhibit microbial growth but do not destroy microbes or prevent, for example, fat rancidity.
Products intended for freezing or quick-freezing must be of good quality. They should be prepared, cooled, and frozen without delay using appropriate equipment to keep chemical and microbiological changes to a minimum. The freezing process should be as rapid as possible, as slow freezing leads to the formation of large ice crystals that damage the structure and promote microbial growth after thawing.
Quick-freezing
A quick-frozen product is a food that has been rapidly frozen and, after temperature stabilization, has reached -18 °C or colder throughout. Facilities and equipment used for quick-freezing and storing quick-frozen products must be suitable for the purpose:
- The equipment must allow adjustment to below -18 °C, ensuring quick-freezing is completed within 24 hours. Industrial quick-freezing commonly uses plate freezers, freezing tunnels, and spiral freezers.
- Storage areas for quick-frozen products must maintain a temperature of -18 °C or colder.
Freezing
Freezing is a less strictly regulated method than quick-freezing and may be slower depending on the capacity of the equipment used. Any freezing device with sufficient capacity may be used for freezing. It is not recommended to freeze food in equipment where previously frozen products are stored at the same time. Quality is best preserved when freezing is rapid, so equipment should not be overloaded and portions should not be too large. Freezing is permitted in both registered and approved food premises. There are restrictions on freezing animal-based products in registered food premises (see the guideline Quick-Freezing and Freezing of Foodstuffs in Food Premises, in Finnish).
Freezing close to the use-by date is not recommended. For example, minced meat should be frozen as soon as possible after mincing and well before the use-by date. Exceptions apply to products donated for food aid and raw materials in professional kitchens when the cooking process includes heat treatment.
In registered premises, products frozen for own use are recommended to be consumed within two months. If more than two months have passed since the freezing date or the best before date, the quality must be verified by sensory evaluation before use. Products unfit for consumption must be disposed of.
Labelling Requirements for Quick-freezing and Freezing
Packages of quick-frozen foodstuffs sold to consumers or catering establishments must include:
- the word “quick-frozen”
- the minimum durability date and the period during which the product may be stored by the purchaser
- the storage temperature
- the statement “do not freeze again after thawing”.
The packaging of frozen food must include the word ‘frozen’, storage instructions for the product, and the statement "do not freeze again after thawing".
For packaged frozen or quick-frozen meat, raw meat preparations, and unprocessed fishery products sold to consumers or mass caterers, the date of freezing or quick-freezing must also be indicated.
Thawed products may be sold if it is clearly stated that the product has been thawed and must not be frozen again. The operator responsible for freezing determines the shelf life and ensures correct labelling. Labels must also provide traceability information, and in bilingual municipalities, they must be in both Finnish and Swedish.
Thawing
Avoid thawing quick-frozen and frozen products before actual use. Thawing should be carried out in a cold store or refrigerated area, not at room temperature. Thawed products should be used as soon as possible. As a general rule, food that has been thawed or has started to thaw should not be frozen or quick-frozen again. Exceptions to this rule are specified in the guideline Quick-freezing and Freezing of Foodstuffs in Food Premises (in Finnish).
Remember:
- Do not freeze or quick-freeze expired or poor-quality food!
- Do not freeze food in a fully loaded freezer, as cold air cannot circulate properly.
- Label frozen or quick-frozen products appropriately.
- Maintain the cold chain. Do not allow food to thaw before intended thawing.
- Thaw food in cold conditions, not at room temperature.