Puffed grain

Puffing food refers to a method of treating with heat and pressure, which gives the food a foamy internal structure. The best known representatives are the popcorn ( popcorn ) and the puffed rice, in which starchy plant seeds are puffed. Puffed foods have a very low specific weight and are easy to chew.

Production

When puffing of seed, the water contained in the seeds explosively vaporises due to sudden depressurization. The hot, swollen starch granules of foam on it to many times their original volume and frozen in this state.

Certain types of seed (eg special popcorn for making popcorn ) can be popped by heating alone of whole grains, because the seed coat is capable of a high internal pressure withstand before it ruptures and allows the sudden expansion of the starch contained. In this way, made ​​popcorn the indigenous peoples of Central America was already known.

In grains species whose seed coat does not have the necessary strength (eg, rice and wheat), a pressure vessel is used, in which the raw material is heated dry or with the addition of water. The excess pressure is then released abruptly to trigger the pop up.

Another production method based on the foaming of swollen starch in reducing the pressure, the extrusion of Knabbergebäcken, such as peanut flips. This is a continuous process in which the pressure decrease in the leakage of hot starch slurry takes place from a nozzle. In the same way arises from defatted soybean meal soy meat. This starting material is, however, largely of proteins with only relatively small amounts of starch.

In principle, find an increase in volume, such as in the preparation of puff pastry or prawn crackers food without sudden pressure decrease. This drives produced during heating steam the food continuously. Such preparations are not referred to as " puffed ".

Use

Puffed food are now used mainly for nibbling snacks and confectionery ingredients. Unlike popcorn you will find puffed quinoa grain, amaranth, puffed rice or wheat as an ingredient of cereal mixtures or as the main ingredient of breakfast cereal, as well as part of confectionery, such as chocolate or muesli bars.

Above all, rice is sometimes colored by adding food coloring. A special feature of puffed rice as a part of Japanese Green Tea Genmaicha preparation dar.