The chemical and bio-chemical composition of foods is fundamental to the study of their properties and processing application. The initial skills as learnt by man in the earlier days had been in the food chemistry. A phenomenal growth in the knowledge of biochemistry or food chemistry has since then occurred. The developments in this field have resulted in a better understanding of the biological materials, which we use as food. Still, only a small percentage of the reactions that occur when a food is cooked or processed in some way are known, infact more are being studied every day.Different foods have widely differing nutritional contents and in order to maintain health it is necessary to select foods that fulfill the requirements of a healthy diet. The nutritional requirements vary according to the age, sex, and level of activity of a consumer. Most of the snack foods available in the market are high in energy but contain little protein, vitamin and minerals. Traditional snacks made from rice or other cereals and minor millets are common around the world especially in Asia. The aim of the present research is to provide a unified picture of food from a chemical stand point.