Characteristics of Starch in Argentinean Malting Barley

Abstract

Sixteen samples of malting barley grown in the Buenos Aires Province of Argentina were selected for this study. Starch was isolated and purified using a modified version of the Morrison method. The starch concentration in the samples ranged from 53.2 to 63.3%. The starch samples were characterized physicochemically, and the following results were obtained: 1) the concentration of lipids, phosphorus, and nitrogen was too low; 2) the values for apparent amylose ranged from 19.0 to 23.9%, whereas the values for total amylose ranged from 23.6 to 31.2; 3) the starch had a bimodal granule size distribution?type A (big and lenticular) and type B(small and irregular or spherical); 4) the gelatinization temperature ranged from 62.18 to 64.68°C; 5) amylopectin was responsible for the crystallinity of starch granules; and 6) the granules were birefringent. The last property disappeared when starch was heated above its gelatinization temperature.