Ascorbic acid also known as vitamin C. Vitamin C is Ascorbic acid also known as vitamin C. Vitamin C is very essential for growth and maintenance of the human body. It is necessary for the normal formation of protein collagen, which is an important constituent of skin and connective tissue. The deficiency of vitamin C causes is known as disease "Scurvy". Vitamin C is present in all citrus fruits, gooseberry (Aonla), tomato, apple, pine apple, grapes and other foods. The vitamin C is very sensitive to heat, light, air and strong alkali. Most of the part of vitamin C is lost during heat treatment (processing) like blanching, boiling, cooking, cooking under pressure and sterilization of foods. The apple, lemon, pine apple, grapes, guava, ripe mango, was heated to 60°C, 70°C, 80°C, 90°C and 100°C for different time viz. 15, 30, 45, 60, 75, 90 and 105 minute in constant temperature. The loss of vitamin C is less at low temperature. As, the time of heating is increase, the loss of vitamin C increase. The maximum loss of vitamin C has been found in the first 15 minutes of heating at different temperature, then, further rate of loss of vitamin C becomes lesser due to presence surface oxyge