Physicochemical properties of starches obtained from three varieties of Chinese sweet potatoes

Starches isolated from 3 typical types of Chinese sweet potato varieties (XuShu18, SuShu2, and SuShu8) were characterized and compared with starches isolated from potato and mung bean. The 3 sweet potato starches differed in granule size; particle size distribution; protein, lipid, and phosphorus contents; pasting behaviors; swelling patterns; and syneresis. The retrogradation tendencies, measured both by setback ratio and by syneresis, differed for the 3 starches, although the amylose contents were quite similar (19.3 to 20.0%). Physicochemical properties of all 3 types of starches are evidently different from each other and from those of potato and mung bean starches.