Natural Food Preservatives

Food preserving is a method of storing both raw and cooked food for an extended time by using food preservatives. Food packaging on the other hand, protects food and provides information regarding the packaged food. Food preservatives are substances added to food products to prevent decomposition due to adverse chemical change or microbial action. The main objective behind using food preservatives is to preserve the appearance, texture, flavor, edibility and nutritive value of the foods and also to prevent from food poisoning. Food preservatives can be either natural or man-made substances. Based on their action, they are broadly classified into three. They are antimicrobial preservatives, antioxidant preservatives and another third type preservatives, which target enzymes in the food itself. Antimicrobial preservatives inhibit the growth of microbes such as bacteria and fungi, whereas antioxidant preservatives inhibit the oxidation of fats, lipids and other food ingredients. The third type of preservatives blocks the natural ripening and aging of the foodstuffs after harvest. In addition to using preservatives, there are other healthy ways of preserving food, for example, processes such as drying, salting, smoking, pickling and freezing can also preserve foods.

Natural Food Preservatives

Natural food preservatives include substances such as salt, sugar, rosemary extract and vinegar. Among these, salt, sugar and vinegar are used as an ingredient rather than additives or preservatives. They are preservatives that have been used in the recipe itself, hence they are also called as traditional preservatives. Now, let's see in brief about these natural food preservatives.

Salt: Salt has been used as a natural food preservative since ancient times, especially for meat. Salted meat can last for many years. The phenomenon behind adding salt as a preservative is that it dehydrates microbes through the process of osmosis. Thus, it inhibits the bacteria that cause food spoilage. Salt also protects food from yeasts and molds.

Sugar: Sugar, an organic compound in the form of carbohydrate, has been used as a natural food preservative in many of the food items. Sugar sweetens the food product and inhibits the growth of microorganisms through the phenomenon of osmosis. Foods can be stored either in sugar syrup or in crystallized form, where the food to be stored is cooked in sugar till the point of crystallization. Sugar acts by drawing out water from the bacteria and other microorganisms, which either kills the bacteria or inhibits their growth.

Vinegar: Even though vinegar is acidic, it is not considered a harmful chemical or preservative and hence is used commonly as a natural food preservative. It is prepared by fermenting sugar and water solution beyond the alcohol stage. Nowadays, many people prefer homemade vinegar other than the ones that are sold. Vinegar contains acetic acid at 4-5% concentration. It is the acetic acid that kills microbes and hampers food spoilage. There are different types of vinegar depending upon the sugar base from which they have been made.

Rosemary Extract: Rosemary leaf extract, also known as rosemary oleoresin, has been used as a natural food preservative since a long time. It has been used traditionally for its pleasant aroma and flavor. Rosemary extract is prepared by distillation of rosemary leaves. They serve as a powerful antioxidant that prevents the oxidation of the food constituents, thus preserving the color and flavor of the food. Their antioxidant characteristic is due the presence of natural compounds such as phenolic diterpenes, carnosol, carnosic acid and rosmarinic acid.

Many synthetic food additives are available in the market. These chemical additives should be avoided as far as possible, as many of them are sold without proper testing. There are artificial preservatives that are considered to be safe but it is observed that some toxins and carcinogens are found in them. Hence, to be on the safer side, prefer only natural preservatives and properly certified chemical preservatives. It is recommended to follow food safety rules while handling, cooking and preserving foods.