Ready-to-eat (RTE) foods are invariably dry products. To produce them, grains or grits are subjected to a cooking process that gelatinises the starch and then expands the product, normally through the vapourisation of steam. The expansion process gives RTE foods their characteristic crispy/crunchy texture. The technologies for producing RTE snacks and breakfast cereals are often the same. After processing, savoury flavourings are added to snacks and sweet flavourings may be added to breakfast cereals. Probably the most popular technology for producing RTE foods is extrusion cooking. Extrusion cooking involves a screw turning in a barrel that has small hole known as a die at the end. The screw transports meal through the barrel and subjects it to pressure, shear and heat. The meal melts and turns into a plastic material. As this material emerges through the die, the superheated water within it vapourises expanding the product, producing, for example, the characteristic worm-like corn curl snack. Extrusion-cooked RTE starchy foods are invariably made from decorticated flour or meal. The type of flour is to a large extent immaterial as it is the starch that is the most important constituent. However, this means that the nutrient composition of the extrusion-cooked RTE foods is often restricted to essentially starch and relatively low quality
Ready to Eat
