Importance of Food Preservation
The essentials of good diet are :
- Vitamins : These are a group of substances that are essential in small quantities for normal functions of the body. Their deficiency causes sickness and improper development of body. At present six of these are recognised as essential to human nutrition. These are A, B, C, D, E and K. The richest sources of vitamins are green vegetables, milk, butter, fruits, eggs, etc.
- Proteins : These are complex compounds of carbon, hydrogen, oxygen, nitrogen and sulphur. These are found in eggs, meat, pulses, etc. These build tissues of the body and repair them when torn out.
- Carbohydrates : These are the organic compounds of carbon, hydrogen and oxygen. These are found in rice, wheat, sugarcane, potatoes, starch in maize, etc. These produce heat and energy in the body. Their deficiency causes loss of weight and weakness.
- Fats : These have carbon, hydrogen and oxygen. They are obtained from animal and vegetable kingdoms. Butter, ghee and various vegetable oils are examples of fats. They also produce heat and energy in the body and build fatty tissues.
- Mineral Salts : These make food tasty and are useful for health. They are the sources of hydrochloric acid found in the digestive system. These are found in green vegetables.
- Water : It serves to dissolve food when digested and aids absorption. It helps in removing waste matters from the body. It also helps in circulation of blood.
A balanced diet is one which contains all principal food factors, i.e., vitamins, carbohydrates, mineral salts, fats, water, etc., in correct proportion. This should be able to give about 3,000 calories of energy per day.
Types of Vitamin
- Vitamin A : It increases resistance to infection and tones up the whole system. Its deficiency causes nightblindness, disorders of skin, stomach growth and respiratory diseases. It is found in milk, butter, egg – yolk, ghee, carrot, cod – liver oil, etc.
- Vitamin B : It is present in cereals, peas and beans. It protects the body from nerve diseases such as beri – beri, pellagra, etc., and it cures pernicious anaemia, degeneration of sex glands and enlargement of liver and adrenals. It is also called thiamine. It is considered to be a hormone.
- Vitamin C : It ensures healthy teeth, bones and protects the body against scurvy. It is present in fresh vegetables, orange, lemon, lettuce, tomato, cabbage, turnip, potato and mango.It is also called Ascorbic Acid.
- Vitamin D : It is present in milk, butter, ghee, codliver oil, yolk of eggs and it is also produced under the skin by the rays of the sun. It promotes bone promotion and prevents rickets.
- Vitamin E : It has vital influence on organs to reproduction. Its absence causes sterility. It is present in the germinating wheat. It is also called Alpha – tecopherol.
- Vitamin K : It is found in fish, oats and wheat. It help in the clotting of blood. Its absence cause haemorrhage.