It is a hot summer day and you have just walked into your house leaving the unbearable heat out. You head straight to the refrigerator, pick up the chilled fresh fruit juice pack and pour yourself a tall glass. Aah, fruit juice served fresh out of a box! We all love technology, don’t we? Ever wondered how the juice is manufactured and packed a couple of months ago and still retained ‘fresh’?
This is where food preservatives come in. Did you know food preservation is one of the oldest technologies used by humans? Before the advent of artificial preservatives, natural preservatives such as vinegar, honey, salt, sugar and lime juice were used. But chemical preservatives have become commonplace these days. Some of them include benzoates (for jams, jellies, cheese, pickles), nitrites and nitrates (for packaged meat), propionates (for baking products) and sulphites (for juices and wines).
METHODS OF PRESERVATION
Essentially, preservation inhibits growth of bacteria or fungi, which are responsible for spoilage of food products. Preservation can be done in several ways:
Refrigeration/Freezing: Most popular form of preservation because it retains the taste and texture of food. It slows down the growth of bacteria.
Canning: This does not necessarily mean metal tins, but any container that can be sealed shut. For instance, your milk carton is a can that undergoes ultra high temperature pasteurisation. Milk is then added to the pack and it is sealed shut. The catch is that once you open the container, you have to use the product before it expires.
Dehydrating: Remember the powdered milk you use for tea? Or the dried vegetables that come in packaged noodles? Powdered soup is also an example of a food preserved through dehydration.
Fermentation and carbonating: Yeast is added to the product to produce alcohol, a preservative, during fermentation. Carbonating is used for soft drinks to inhibit bacteria growth.
Irradiation: This means zapping the product with nuclear radiation. It is used to preserve meat and chicken.
IS FOOD PRESERVATION SAFE?
All said and done, it is nearly impossible to avoid products containing preservatives. The good news is that many juices and beverages that do not contain preservatives (at least artificial ones) are now available in the market. However, it is best to keep an eye out for harmful preservative agents. Read your labels carefully.
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