Evaluation of Starch, Amylose and Amylopectin Content of Three Iranian Wheat Cultivars (Alvand, light BakKeras, Sirvan) and Effect of Two Physical (Ultrasonic Waves) and Chemical (Epichlorohydrin) Corrective Treatments on Their Properties

Starch and its derivatives have several applications in food and other industries. Changes in the structural properties of starch affect their physico-chemical and functional properties.

In this study, after determination of starch, amylose and amylopectin contents of three Iranian wheat varieties (Alvand, light bak kras and Sirvan), modification of their characterizations were accomplished with cross linking creation with “epichlorohydrin” in (0.1%, 0.3%, 0.5% v/w) level and physical modification by ultrasounic waves in 28 KHz frequencies in two times (15 and 30 minutes) at 20 °C. Qualitative properties of the samples such as paste clarity, water binding capacity, viscosity, solubility, swelling power and freezing thawing stability (Syneresis) of native and modified samples were examined.The results were analyzed in a completely randomized design-factorial test and the means were compared based on the least significant difference.

The results indicated the solubility, swelling power, paste clarity and water binding capacity of physically treated starch varieties were increased as compared to the native granules. Whiles, starch modification with epichlorohydrin decreased solubility and consistency of treated starches. The changes of paste clarity and water binding capacity in chemical modified starch in comparison to the native samples are different in varieties. Viscosity of all modified samples in comparison to the native form was decreased and their synersis were increased.

  Modification treatments are effective in many qualitative properties of starch and effectiveness of different starch varieties on physical and chemical treatments are different due to difference in genetic characteristics of starch.