5. Conservation and storage of food
The maximum time a food retains all its organoleptic, nutritional and health properties is called shelf life.
The most frequent and traditional conservation systems used are:
PACKAGING AND LABELLING
Packaging, in addition to protecting the food, also has the function of facilitating distribution and use (dosing).
The labels of the products must inform us of everything related to the food it contains, and must contain certain mandatory information:
The lot is very important, because it is related to the traceability of a product. By traceability we mean the «ability to trace or reconstruct the life of a food from its origin to its sale to the final consumer «.
Types of food preservation
Preserving food consists of preventing the action of contaminating agents that can contaminate it and alter its original characteristics (smell, taste, appearance).
- Freezing and deep-freezing are the food preservation processes that cause the least changes in the food, especially ultra-freezing, since the ice crystals formed during the process are smaller and do not damage the food tissues.
Preservation by heat
The methods of preservation by heat are as follows:
- Uperization (UHT): is a system where we apply a high temperature for a very short time, but enough to eliminate all microorganisms and their spores, and make the food suffer as little as possible by this heat treatment. Ex: UHT milk (we can keep it outside the fridge).
Chemical preservation consists of the addition of substances that chemically modify the food, for example by lowering its PH.
- Acidification: consists of reducing the pH of the food, thus preventing the development of microorganisms. This is done by adding acidic substances such as vinegar to the food.
Preservation by dehydration
- Lyophilization (freeze-drying): consists of the drying of a previously frozen food. It is a process that allows the maximum conservation of the original quality of the food and its nutritional value.
Preservation through the use of additives
It consists of the addition of additives. These additives can be:
- Industrial origin: This is one of the most commonly used food preservation techniques. It is used with the sole purpose of improving food characteristics such as lengthening shelf life, improving flavour, colour or texture. They are not used to fortify food with nutrients.
Conservation by irradiation
It consists of the application of ionizing radiation on the food (under strict control). It is a very effective method, as it prolongs the shelf life of food in the best conditions. Foods that have undergone the preservation process by irradiation must be labelled as follows.
Food packaging and labelling
Once the food product is suitable, it must be protected from possible external contamination (from the environment, from the handler, from other foods...). That's why it is packed.
Packaging, in addition to protecting the food, also has other functions such as: facilitating distribution and use (dosage).
The materials directly in contact with the food and with which it will be packaged depend on the type of product. They can be: plastic, glass, tinplate or aluminium. The characteristics of the containers that are in direct contact with the food must:
- Contain a label to give information about the product to the consumer.
The LABELS of the products must inform us of everything related to the food it contains, and must do so in a clear and legible manner. Below we will explain the requirements for all products, although depending on the type of food this label may vary slightly:
- Lot: code with which we could "track" that product in case of problems with it. These are products that are manufactured or packaged under similar circumstances.
The lot is very important, because it is related to the TRACEABILITY of a product. By traceability we mean the "ability to trace or reconstruct the life of a food from its origin to its sale to the final consumer". This means knowing where the food has passed at all times, and if there is a problem, being able to remove the products in time, so that there is no foodborne disease.
It must be ensured that the consumer will see the label, that it will not be changed, and that products will not be sold without labels.
There are practices that are not allowed with regard to labelling such as re-labelling products (this is considered fraud, as we may have changed data such as the expiry date...).