Module 3, Unit 2, Level: Basic
Conservation, vacuum, sealing, modified atmosphere
The purpose of vacuum packaging is to avoid the use of chemical substances to preserve the food, whether fresh or processed, extending its life, keeping its flavor, aroma, color and nutritional qualities unchanged, delaying the ripening and discoloration of the food, and preventing the development of unpleasant odors and flavors, without the potentially harmful effects of preservatives on our body.
The conservation can be done in the refrigerator, in the freezer (in a professional environment, the freezer should be properly cooled), or simply in the pantry.
This technique optimizes the level of hygiene in the kitchen and streamlines the process of preparing and cooking food.
It also makes it possible to store the food of each season for later consumption, reducing the environmental footprint and fighting food waste.
In terms of management, vacuum packaging and conservation is an ally of kitchen professionals, saving space and optimizing storage, and facilitating the creation of menus.
Vegetables (cabbage, white cabbage, cauliflower, pumpkin, carrot, onion), fruit (apple, pear, pineapple), legumes (beans, peas, broad beans), tubers (potatoes), cereals (rice, corn, wheat), fish (sea bream, mullets, sea bass, trout), meat (goatling, poultry, pork), seafood (shellfish, bivalves, crustaceans), jams and marmalade, pastry creams.
Kitchen professionals should have great care when handling and preparing food products to package them in a vacuum.
To avoid incidents, certain practices must be respected, such as:
- use appropriate bags or packaging containers to prevent the exchange of gases and odors or their rupture due to the pressure of the inserted gas. In the case of sous vide cooking, the packaging must be made with retractable bags, conceived for that purpose.
- check the condition of the containers with food regularly, as they can implode or break due to depression, constituting a risk of entry of atmospheric air, which will change the entire flavor and texture of the packaged ingredients;
- check that the vacuum machine is working properly.
It is also possible to pack food in vacuum at home applying several techniques:
- use a domestic vacuum packaging machine;
- use containers with special lids and the aid of a vacuum pump;
- remove excess air inside the package through a tube, or leave only a small opening, press the food, and quickly close the package.
The techniques described above do not remove all of the air inside the package, with implications in the durability and conservation of the product.
The durability of vacuum packaging is related to the characteristics of the food product. According to available information, vacuum packaging has a durability of 15 to 17 days; if it is vacuum packaging with inert gas, it has a durability of 30 days. The durability of the food product could be longer if vacuum cooking reaches pasteurisation temperature.
Good practices in professional environments recommend products packaged in a vacuum to be regularly sent for laboratory analysis.