All constituents of food-carbohydrates, fats, proteins, vitamins, minerals, fibre and water are necessary for the proper growth of the body. We get these nutrients from food materials like wheat, jowar, pulses, rice, vegetables, fruits, etc. However, what will happen if these food materials are infested by insects or spoiled in any way?

Food spoilage

Factors responsible for food spoilage

Sometimes, fruits or their skins turn black. Some foodstuffs give out a foul or bad odour. Such foodstuffs are not suitable for us to eat. Sometimes, naturally available food materials are spoiled by wrong handling as when they are over[1]cooked, or improperly stored, say in a damp place. In such cases, the quality of the food materials deteriorates. They may also be spoiled during transportation. Can you give more such examples of food spoilage ?

On a day out with our friends or family we enjoy mouth-watering dishes like pani-puri, shev[1]puri, pav-bhaji, vada-pav, pizzas, burgers. But, have you ever given a thought to how or where they were made ? Were they displayed and served hygienically ? What was the source of the water used for preparing them? Discuss all these matters with your science teacher.

Which fruits in the picture appear to be good to eat ? Why? Various kinds of changes occur in food materials. For example, fruits turn black or change taste, meat becomes sour or peanuts become rancid. All these changes occur due to factors within the food materials. Often, food grains, etc. produced in farms are damaged due to various reasons like improper handling, improper storage, improper transportation, etc. Some foodstuffs like meat and milk are either acidic or alkaline. They may get spoiled due to chemical reactions on contact with metals. Sometimes, foodstuffs may be spoiled due to contamination by micro-organisms or insects from the surrounding air, water or soil. Can you give some other examples of factors that cause spoilage of food ?

Food wastage

With the help of science and technology, India has shown great progress in the production of various foodstuffs like cereals, fruits, vegetables, fish as well as milk and milk-products. Even so, many people in our country and all over the world face the problem of hunger. Many do not get even one meal a day. Hence, it is our duty to prevent wastage of food wherever it takes place.

 Quantitative wastage of food :

Wrong methods of farming like hand sowing of seeds, inadequate threshing, improper storage and wrong methods of distribution are some reasons for quantitative wastage of food. Besides, much food is wasted as a result of the custom of offering and serving too much food to guests at traditional feasts or banquets. Had it not been wasted, all this food could have met the need of many others.

Qualitative wastage of food : Using wrong methods of protecting food, excessive use of food preservatives, over-cooking, washing the vegetables after cutting them, mis-handling of fruits like grapes and mangoes, mis-calculation of the time required to transport food from producers to consumers, are some of the causes of qualitative wastage of food.

Food storage and preservation

 We have learnt about various methods of safe storage of food like freezing, drying, boiling, air-tight packing, etc. These different methods prevent the growth of micro-organisms in food and thereby save the food from spoiling.

Food protection and food preservation

Food protection : Prevention of food spoilage by microbial growth and infestation by pests is called food protection.

Food preservation : Use of various preservatives to prevent, for a long period of time, food spoilage due to internal factors is called food preservation.

The health of all people, young and old, poor or rich, is endangered by food adulteration. Different types of adulterants affect our health in different ways. Some adulterants cause abdominal discomfort or poisoning, while some may affect the functioning of some organs if consumed over a long period of time, or even cause cancer.