Food Preservation
It is a branch of manufacturing that transforms raw animals, vegetables, or any other eatable materials into tasty, nutritious and safe food products. Food processing includes all the steps from food harvesting period to the time it arrives to the market. Food preservation has different processes like picking, sorting and washing etc to preserve the food. Processing involve an extremely complex set of techniques and ingredients to create safe and eatable food. These food preservation techniques destroy proteins and enzymes etc which are responsible for spoiling the food.
The preservation has its own importance. Generally, preservation of food is done during the month when the production is in bulk and available in large quantity. This is the most important reason of food preservation is to preserve the excess production of food.
The second other main reason of food preservation is to add variety to the meals. You can buy seasonal vegetables throughout the year thus adding variety and taste in your food. The seasonal vegetables and fruits can be used throughout the year since they are preserved. Also, preserved food can be export to other countries for their consumption thus bringing revenues to your economy. For e.g. Some of European countries have only strawberries cultivation while major part of India has only wheat and rice cultivation. The two countries can exchange their products after preservation so that the eatables must be safe and nutritious to eat. The food must not get spoiled while covering the geographical distance. In this way preserved food can be reached to the area where the food item is not grown.
Food is said to be spoiled if there is fermentation, spongy growth, bad odour and bubbles of gas in the food etc. The bread having spongy growth is unfit for consumption similarly growth of soft brown spots on vegetables and fruits are also unhealthy to consume. Since food is an organic substance it gets spoiled because of enzymes, micro-organisms and other favorable decaying organisms. Food having high moisture content kept for a longer period of time at room temperature has very strong chances to get spoiled because of the favorable conditions for the growth of microorganisms over the eatables.
Every eatable food has continuous enzyme reactions for their growth and decay. The growth of seeds into flower and later into fruit is because of enzymes only. These enzymes are responsible for the continuous growth and then fermentation and decaying of vegetables and fruits. Consider an Apple which is red and fresh but after some days it got a black spot on it showing that it got spoiled. This has happened because of the continuous growth and reactions of enzymes on the Apple.
Because of such reasons food preservation is a compulsory process. Every method has its own importance and significance in the process. The food preservation is a long and time consuming process. On an average near about 3000 different types of additives are present in food as indirect additives. These additives are used to preserve food for the longer period of time. The other process used in preservations are Canning, Salting, Pasteurizing, Carbonation, Chemical preservation, Refrigeration and freezing and Dehydration etc. The process of Refrigeration and freezing are used on almost all foods and beverages.
The description of the major preservation process are as follows:
Canning: The food has micro organisms also which keep on disintegrating the food. Bacteria need moisture to grow and favorable temperature. Canning is the process in which the food is kept in the air- tight container and heated to destroy microorganisms. It involves high heat processing having biggest disadvantage that water-soluble nutrients can be lost making food less nutrients and healthy to consume.
Salting: It is the oldest method of preservation. The process is use to dehydrates the bacteria which will stop its growth. The process of salting is commonly used to preserve meat. The effect of salt is more in cold weather. Although method is effective but for a shorter period of time and it is primitive so in modern period it got replaced by refrigeration and freezing. The other main important reason why refrigeration and freezing has replaced salting is that the act of boiling food during the process of Salting generally changes its taste and texture.
Chemical Preservation: The three basic kind of chemicals used in food are Benzoates, Nitrites and Sulphites. Under specific conditions, these substances does not support the growth of microorganisms without affecting the quality of food. Some other chemicals like Sorbic acid kills the bacteria and preserve the food for a longer period of time. These chemicals are used in the prescribed quantity only and need to be mentioned on the container pack. Some of them are also used as oxidizing agents but mainly used in curing of meats.
Refrigeration and freezing: These are the most popular forms of food preservation methods in today's time. These are common in use since it has no effects on Refrigeration and Freezing. This is a major reason of its wide popularity. Refrigeration and freezing lowers the pace of action of bacteria on the food preserving it for the longer period of time.
Dehydration: This is also a modern method to preserve the food. Dehydrated milk, soups and sauces and dried meats and dried fruits and vegetables etc are all the examples of Dehydration. Most of the bacteria, either they die or become inactived during the process of dehydration. The process of steaming, coating on fruits and vegetables with acids are used under dehydration.