Comparison of physicochemical properties of very small granule starches from endosperms of dicotyledon plants

In this study, 6 very small granule starches (VSGSs) were isolated from endosperms of dicotyledon Amaranthus cruentus, Agriophyllum squarrosum, Chenopodium quinoa, Euryale ferox, Mirabilis jalapa, and Vaccaria hispanica. Their morphologies and physicochemical properties were investigated. Most VSGSs with granule size <3 mu m were spherical or polygonal, and their apparent amylose contents ranged from 19.4 to 33.1% with A. cruentus starch the lowest and E. ferox starch the highest. All VSGSs had the same A-type crystalline structure with relative crystallinities from 23.3 to 29.6%. Though 6 VSGSs had slight differences in short-range ordered structure and lamellar repeat distance, their lamellar peak intensities exhibited significant differences. The gelatinization temperatures showed significant differences among 6 VSGSs with C. quinoa starch the lowest and M. jalapa starch the highest. The 6 VSGSs had significantly different pasting viscosities with peak viscosities from 1887 to 4579 mPa s, hot viscosities from 1704 to 3479 mPa s, breakdown viscosities from 56 to 1170 mPa s, final viscosities from 2419 to 4811 mPa s, and setback viscosities from 715 to 1821 mPa s. The digestion properties of starches were significantly different among 6 VSGSs. The above results could provide some references for applications of these VSGSs. (C) 2020 Elsevier B.V. All rights reserved.