One of the factors that accelerates food spoilage is oxygen.
Its presence causes many unfavorable changes: autoxidation of fats (rancidity), change in taste and smell, deterioration of color, oxidation of vitamin C, vitamin E, beta-carotene and some amino acids, as well as the development of aerobic microflora, especially mold...
Reducing the durability of food (spoilage) may occur as a result of the action of oxygen, water, light and microorganisms. The purpose of food preservation is to prevent the development of microorganisms and to inhibit unfavorable chemical and physical changes occurring in stored products. By preserving food, we extend its shelf life.
By limiting the access of oxygen to the product, the shelf life of many food products can be extended. Reducing the product's contact with air means it stays fresh longer and can be safely consumed. By removing oxygen from the environment, you can inhibit the growth of aerobic bacteria, yeasts and molds that cause food spoilage.
One of the methods of food preservation that can be used, among others, in catering establishments, is vacuum packaging.
The product is packed in plastic or aluminum foil with low oxygen permeability, air is pumped out of it and closed hermetically. Food packaged this way can be stored longer than fresh food.
Products in vacuum packaging are characterized by good sensory quality, greater microbiological stability and lower weight loss.
Vacuum packaging is useful for products with a high fat content, as oxygen causes them to turn rancid quickly. Vacuum packaging is also a particularly good way to store food that has already undergone heat treatment under refrigerated conditions (temperature 4°C).
The refrigerated storage time of fish is longer if it is vacuum packed and its microbiological quality is better. Vacuum packaging shrimp is also a better way to extend shelf life compared to storing them exposed to air. Shrimps stay fresh in refrigerated conditions for a week, and in vacuum-packed conditions - three weeks.
The text comes from "Przegląd Gastronomiczny"
Archive 5/2006
Autor:
dr inż. Dorota Czerwińska
Katedra Żywienia Człowieka
Wydział Nauk o Żywieniu Człowieka i Konsumpcji
SGGW Warszawa
