Riley, Cliff K.; Wheatley, Andrew O.; Asemota, Helen N.
Author Affiliation, Ana.
The physicochemical properties of starches from yams (Dioscorea spp.) grown in Jamaica
European Journal of Scientific Research
Date of Publication
Starches from five Jamaican yam (Dioscorea sp.) varieties were isolated and characterized according to their physicochemical properties. Starch accounted for 523.52 to 849.12 gKg-1 of the tuber's dry weight, with round or oval shaped granules ranging from 5.4Ám to 34.4Ám in diameter. The apparent amylose content ranged from 111.44 + 0.33 gKg-1 for Chinese yam to 265.30 + 0.09 gKg-1 for Round Leaf yellow yam. X-ray diffraction studies revealed three distinct crystalline patterns, where bitter yam starch displayed the type A pattern, Round Leaf yellow yam, White yam and Lucea Yam starches the type B and chinese yam the intermediate C pattern. the temperature of gelatinization and range of gelatinization also varied significantly among the different yam starches studied, where Round Leaf yellow yam had the lowest peak temperature (67.74 oC) and the Chinese yam the highest (78.85 oC). Bitter yam starch gelatinized over the widest range (13 oC) and the White yam the shortest (6 oC). The differences observed in the different starches may prove suitable for use as binders in pharmaceutical formulations.....