Effect of Water Stress and the Addition of Shriveled Wheat Kernels on Milling Performance and the Physiochemical and Rheological Properties of Syrian bread Wheat Flour

Abstract

Wheat is widely influenced by the environmental conditions which in turn affect kernels quality. Drought is unfavorable environmental conditions affects wheat crop resulting in shriveled kernels and thus reduces flour extraction rate. Consequently the aim of this research was to investigate the physical, chemical and rheological properties of sound and shriveled kernels of bread wheat. The Syrian bread wheat variety Cham₈ was selected, in addition to shriveled wheat samples of the same variety. Samples were milled into flour to determine the kernels milling performance and flour chemical and rheological properties according to the AACC approved methods. Milling performance of wheat kernels revealed a significant reduction in flour extraction rate of the shriveled kernels compared with the normal ones, where the flour extraction decreased by 9.44%. The chemical characteristics of the wheat flour samples demonstrated a significant improvement in gluten quality and quantity of the shriveled kernels flour comparing with the sound kernels flour. However, ash content and flour colour were increased. Moreover, flour extracted from the shriveled wheat kernels revealed better farinograph parameters than the normal wheat kernels flour. Nevertheless, dough extensibility and maximum resistance to extension increased as measured by the extensograph technique. Elevated shrunken wheat kernels accompanied with reduction in flour yield and improved gluten quality and farinograph properties and changes in dough elasticity.