Relationships between Grain Physicochemical and Mec hanical Properties of Some Iranian Wheat Cultivars

Abstract

Physicochemical and mechanical properties of wheat grains can have a great impact on the quality of the final products (bread). Therefor e, correct selection of wheat cultivar for specific applications seems to be crucial . In this study, the differences in the physicochemical and mechanical properties (under co mpression and impact loadings) of ten Iranian wheat cultivars (Azar2, Alamut, Bam, Ba har, Chamran, Shiraz, Falat, Keras Adl, Marvdasht, and Nicknejad) were studied. Moreov er, the relationship between these properties was investigated. The results indicated that the type of cultivar had significant influences on physicochemical and mechanical proper ties. The results of regression analysis between physicochemical and mechanical pro perties showed a significant correlation between protein content and particle si ze index (r 2 = 0.6). Moreover, the protein content could be significantly correlated w ith the parameters obtained from mechanical tests (r 2 > 0.50). Among the mechanical parameters obtained f rom compression and impact loading, the apparent elasti c modulus and the specific breakage energy established maximum correlation (r 2 = 0.77 and 0.78, respectively) with the protein content. Similarly, significant correlations were f ound between particle size index and mechanical parameters (r 2 >0.60). Hence, the wheat protein content and partic le size index, which have great impacts on quality of the f inal product, can be estimated by a few simple mechanical tests on the wheat kernels. Keywords: Compression test, Impact test, Particle size index, Protein, Toughness.