Zein

Zeins are a group of proteins from Zea mays, which occur as storage proteins in maize kernels.

Properties

Zeins are colorless, odorless and tasteless, slightly soluble in water and edible. Zein is one of the alpha - prolamins and has relatively high levels of the amino acids glutamine, proline, alanine and leucine, and several repeats in their amino acid sequence. In maize zein proteins of 22 kDa and 19 make kDa approximately 70 % of the storage proteins from. They consist of nine oblique cylindrically arranged antiparallel helices, respectively. Zein of 22 kD encoded by 23 genes in a gene cluster, which are differentially regulated in their expression.

Zein proteins are approved as a coating for tablets and food in the U.S. and classified by the USFDA as Generally Recognized As Safe. The extraction takes place from corn flour or corn proteins (as coupled use ) by alkaline water and isopropanol extraction with sodium hydroxide. By cooling or by extrusion in an acid bath containing a precipitate of zein forms.

Zein is a thermoplastic material in bioplastics development, partly as a mixture with starch -based fillers.

Zein was from 1948 to 1958 used as a raw material for regenerated by the Virginia - Carolina Corporation under the trade name Vicara in blends with wool, nylon, cupro ( 25% each ), as Vicara alone tended to shrink and was less resistant to abrasion.