Effect of Kernel Size and Its Potential Interaction with Genotype on Key Quality Traits of Durum Wheat

Abstract

This study was conducted to evaluate the influence of kernel size and its potential interaction with genotype on durum wheat quality with emphases on kernel physical characteristics, milling performance, and color-related quality parameters. Wheat samples of seven genotypes, selected from the 2018 Canadian durum variety registration trial, were segregated into large (LK), medium (MK), and small-sized kernels (SK). In general, the kernel size greatly affected the durum wheat milling performance. Within a given size fraction, a strong impact of genotype was shown on the test weight of SK and the milling yields of MK and LK. Particularly, the MK fraction, segregated from the genotypes with superior milling quality, had a higher semolina yield than LK from the genotypes of inferior milling quality, inferring the importance of intrinsic physicochemical properties of durum kernels in affecting milling quality. SK exhibited inferior milling quality regardless of the genotypes selected. A strong impact of genotype was shown for the total yellow pigment (TYP) content and yellowness of semolina, while the kernel size had a significant impact on the brightness and redness of the semolina and pasta. Despite SK possessing much higher TYP, the semolina and pasta prepared from SK were lower in brightness and yellowness but with elevated redness.

Impact of Quality Improvement and Milling Innovations on Durum Wheat and End Products

“…Drought and heat are major abiotic stresses affecting durum wheat production and quality worldwide. In addition to the yield loss, the effects of drought and heat stresses have a very significant impact on durum quality, as indicated by a lower test weight, smaller kernels, lower milling yield, and higher semolina ash [ 18 ]. Enhanced heat and drought tolerance of wheat is not only to ensure a stable yield across both good and bad seasons while maintaining a high yield under optimal conditions, but also to protect quality by minimizing their impacts on kernel morphological properties, which, in turn, adversely affect milling quality.…”

“…They also suggested that kernel size uniformity is very important in the milling process with respect to cleaning, conditioning, debranning, and grinding. Recent research on the relationship of kernel size and genotype on milling performance further substantiates the importance of these aspects for the selection of appropriate durum wheat [ 18 ]. Often the semolina quality specified requires the blending of two or more wheat types to achieve the desired quality of the blend.…”

The Effect of Different Nitrogen Fertilizer Rates, Sowing Density, and Plant Growth Regulator Application on the Quality and Milling Value of Triticum durum Desf. Grain

“…The ash content of grain is an indirect indicator of the ash content and purity of semolina. Grain with high ash content (1.18-1.24%) decreases semolina brightness and yellowness, thus compromising pasta quality [2,15].…”

“…Grain quality is also significantly influenced by the content of the yellow pigment, a trait that is genetically conditioned, stable, and not significantly affected by agronomic or environmental factors [15,16]. The yellow pigment is associated with the presence of natural carotenoids in semolina, and it is responsible for the desirable yellow color of pasta.…”

“…Numerous studies have demonstrated that the physicochemical properties of durum wheat grain affect its milling properties and the quality of semolina [15,27,28]. In the milling process, bran and germ are separated from the endosperm, and kernel brittleness contributes to semolina contamination with bran particles [3,29].…”