Characterization of the chemical and structural properties of native and acetylated starches from avocado (Persea americana Mill.) seeds

Abstract

Avocado seeds are discarded as by-products during pulp consumption or processing despite their high starch content. This study aimed to characterize the chemical, morphological, and functional properties of the native and acetylated starches extracted from avocado seeds. The granules of native avocado seed starch exhibited an oval shape and A-type crystallinity pattern, while the acetylated form obtained with 0.07 degree of substitution (DS) yielded granules with a rounded bell shape and C-type pattern. The solubility and swelling power (SP) of the native and acetylated forms of avocado seed starch increased with increasing temperature; however, at 55°C and 65°C the acetylated form exhibited a higher solubility index (SI). The acetylated avocado seed starch showed reduced breakdown and synergy during freezing, as well as greater oil absorption, compared to the native form. These results showed that acetylation improved the functional properties of avocado seed starch, thereby increasing its potential for use in food products.