What is food?  
  What happens to the food we eat?  
Our nutrient needs  
  Energy balance  
  Nutritional status  
  Laws & labels  
  Additives & colours  
  Toxicity in food  
  Processing food  
  Stability of food nutrients
  Storage life of foods  
  Food- associated health problems  

- Stability of Nutrients in Food -

The stability of nutrients in food depends on their environment.

Nutrients can be lost to varying degrees depending on whether the food is exposed to light or air, acid or alkali, the temperature and their ability to dissolve in water. Generally the losses of carbohydrate, fat, protein, vitamin K, niacin, biotin and elements are small during processing and storage. Greatest losses are usually seen with vitamins B-l and C, with intermediate losses shown by vitamin A, provitamin A and vitamins D, E, B-2, B-6, B-12, pantothenic acid and folacin.

Losses may be due to destruction of the nutrient or by dissolving in water that is later thrown away. The presence of acid (from other foods or addition of vinegar) or alkali (from other foods or added sodium bicarbonate (baking soda)) can cause destruction of some vitamins.

The stability characteristics of nutrients are shown in Figure 32.

Food Facts
Stability of nutrients in food
32: Stability of nutrients in food