Puffing of food is done by using high temperature, pressure, or extrusion. In puffing process expansion of seed is carried out and at that period the vapor pressure escapes through the micropores of the grain structure due to high pressure or thermal gradient. There are different methods of puffing viz. dry heat, sand and salt treated, hot air popping, gun puffing, popping in hot oil, and microwave heating. A wide range of cereals and millets used for puffing such as rice, wheat, corn, sorghum, and ragi.