Study on Physicochemical Characteristics of Waxy and High‐amylose Wheat Starches in Comparison with Normal Wheat Starch

Abstract Waxy and high‐amylose wheats are genetically modified cultivars produced firstly in Japan. The physicochemical properties of waxy and high‐amylose wheat starches were investigated and compared to those of normal bread‐wheat starch. The waxy wheat starch (˜ 1% of amylose) showed higher gelatinization temperature, transition enthalpy and crystallinity of granules than the normal and high‐amylose wheat starches. The paste of waxy wheat starch had higher peak viscosity and swelling power, lower pasting temperature and final viscosity, which are favorable for producing Japanese white‐salted noodles (Udon) of high‐quality. In contrast, the high‐amylose wheat starch had higher amylose content (37.5%), blue value and wavelength of maximal iodine absorption but lower gelatinization temperature and crystallinity than the normal wheat starch. The paste of high‐amylose wheat starch had lower peak viscosity, breakdown and final viscosity than that of the normal wheat starch. These properties of the high‐amylose wheat starch contributed to improve textural properties of noodles which were similar to durum wheat noodles.