People need to preserve food for their future consumptions. There are wide varieties and types of foods the reason why, there are different methods of storing or preserving them.
Foods need to be preserve in order to prevent food spoilage. The most common cause of food spoilage is the presence of microorganism such as bacteria and molds. Eventually, insects, mites and rodents also cause spoilage on foods as they carry these microorganism aside from carrying transmittable diseases. Metabolic change in raw foods may also cause food spoilage. Metabolic change is cause by the presence of enzymes the may cause the breakdown of tissues. Another thing is the Oxidation wherein the fats become rancid and produces off-colors and flavors in some of the foods.
To prevent these spoilage, different methods were used to preserve different types of foods.These preservation methods are the dehydration, the application of chemical additives, the heat processing, refrigeration and irradiation process.
Dehydration is a preservation process wherein water from foods are extracted. The bacteria will now be prevented to multiply because the water content of the food was lost. This method could also prevent some chemical activities in the food.
The use of chemical additives can also be done to preserve foods. Most chemicals that are used as preservatives are salts, acids and sugar. Sugar and salt extracts waters from the food’s tissues by the means of osmotic activity. When the concentration of sugars exceeds form 50%, the growth of the microorganism will be stop. In salt, the 5% solution will reduce microbial activity,10% will prevent the growth of most of the microorganism and 15% will prevent the growth of those more salt tolerant microorganisms.
Heat processing food preservation is used to kill microorganism through the heat, as well as to stop the activities of enzymes. This method can be done in canning, pasteurization or blanching.
Refrigeration is used to preserve food through freezing the food. This activity will prevent the microorganism to spoil the foods as these organisms cannot survive in the freezing environment. Refrigeration can be considered as today’s most common type of food preservation because of the advent of the refrigerator.
Irradiation is a kind of food preservation wherein the gamma rays or high-speed electrons are used to destroy micro-organism that causes food spoilage. However, the foods that undergone this kind of preservation process are still not approved by the food regulating authorities because it was found out that irradiation process also affect the food’s molecular structure.