Comparison of starches separated from different Dioscorea hulbifera Linn, cultivars

摘要

The physico-chemical, morphological, thermal, and crystal properties of the starches separated from three different rhizomes of Dioscorea bulbifera Linn. (D.BLH, Hubei; D.BLG1, Guangxitianlin; D.BLG2, Guangxiyulin) were studied and compared. A light microscopic technique was applied in order to quantify the integrity and shape of the starch granules after isolation. Amylose contents of different cultivars were in the range of 12.18-14.34%. Moisture content, ash content, swelling power, solubility, water-binding capacity, and protein content of starches also differed significantly. The three different D. bulbifera starches all showed a typical C-type pattern with crystallinity 45.36,27.10, and 53.04%, corresponding to D.BLH, D.BLG1, and D.BLG2, respectively. The starch separated from the three starches above showed gelatinization range of 10.09, 11.55, and 7.26°C, corresponding to D.BLH, D.BLG1, and D.BLG2. The enthalpy of gelatinization (DELTA H_(gei)) ranged from 1.28 to 3.11 J/g. Correlation analysis displayed that amylose content and relative crystallinity values were important in determining thermal starches.