Physicochemical, Structural and Rheological Properties of Chestnut (Castanea sativa) Starch

Abstract

Chestnuts have high starch content, which makes them an alternative source of starch for the food industry. Brazil is a country where the production of chestnuts has been increasing in recent years. The aim of this study was to extract starch from chestnuts (Castanea sativa), to characterize its physicochemical, structural and rheological properties, and to compare the results with corn starch. Chestnut starch presented light color, and granules smaller than corn starch, with various dimensions, suggesting a bimodal distribution. Chestnut starch showed 20.48% absolute amylose, higher amylopectin branched-chain length and B-type crystallinity. The infrared spectra of chestnut starch showed characteristic peaks at 1647, 1157, 1079, and 1018 cm-1. Chestnut starch presented higher peak viscosity, breakdown and setback, and lower pasting and gelatinization temperatures than corn starch. The swelling power and the solubility of chestnut starch were significantly higher than those of corn starch. Chestnut starch showed characteristics of a gelling and thickening agent, with potential for use as an ingredient in the food industry, as an unconventional starch from an alternative source.