Kernel quality characteristics, semolina milling potential, dough rheology and pasta making properties of kernels from nine fully irrigated Syrian durum wheat genotypes were observed. Protein content of the kernels exerted a significant affect on the physical characteristics hardness and the degree of kernel vitreousness, both of which were highly correlated with superior end-use product. Gluten composition of semolina appeared as significant as overall protein content in determining the optimum end-use product cooking quality (cooking time and pasta texture). The final viscosity of durum flour exhibited positive correlations with semolina recovery, protein content, gluten content, vitreousness, the optimum-cooking time of pasta and pasta firmness. This indicates the relevance of using the rapid visco analyser technique in evaluating the durum wheat and pasta qualities. Dough rheology measurements confirmed that farinograph and extensograph are useful indicators of the cooking properties of pasta. The research also illustrates that although variability between Syrian durum wheat genotypes were observed, their milling and processing parameters were similar to those previously reported for Canadian and American durum wheats, indicating the potential to use these lines in mainstream pasta production.

Some physical and chemical characteristics of nine Syrian durum wheat genotypes were determined in order to investigate the relationships among individual kernel components and kernel quality. All genotypes were grown on fully irrigated plots in Syria. Test weight, 1000-kernel weight, kernel size distribution, hardness and semolina extraction rates were determined along with the chemical characteristics of the kernel (ash, moisture, protein, wet gluten, starch content and falling number). All tested genotypes had high test weight (83.1-85.9 kg hl )1 ) and 1000-kernel weight (42.5-55.5 g) indicating high milling yield potential. Additionally, all the wheat genotypes demonstrated high falling numbers (433-597 s). Correlation coefficients among the quality properties showed that moisture content did not demonstrate any strong correlations with the studied quality parameters. Protein content exhibited a positive correlation with vitreousness (r ¼ 0.78), and a negative correlation with ash content (r ¼ )0.57). Test weight exhibited a negative correlation with 1000-kernel weight (r ¼ )0.66), and a positive correlation was observed between test weight and starch content of the kernel (r ¼ 0.78). The results illustrate the commonality between Syrian durum wheat genotypes and US and Canadian durum wheat genotypes reported by researchers previously.

The physiochemical composition of durum wheat cultivars was studied in order to investigate the influence of vitreousness on the chemical composition of starch and its thermal and pasting properties. Six durum wheat lines were chosen and grown in northern Syria. Grains of each cultivar were visually sorted according to the degree of vitreousness into fully vitreous and fully starchy fractions. Amylose/amylopectin ratio and total starch was determined using Megazyme methods, while thermal and pasting properties were determined using DSC and RVA. Starchy kernels were higher in total starch than vitreous kernels but showed a decreased amylose content. Negative linear relations were found between amylose content, and both peak viscosity and breakdown. Trends in variation of gelatinisation characteristics were observed between vitreous and starchy kernels from the same cultivar, with higher total enthalpy being associated with starchy grains compared with vitreous grains of the same line.

The physical and chemical characteristics of five Syrian durum wheat cultivars grown under varying environmental conditions were investigated. Two cultivars were grown under irrigated conditions whilst two were grown under rainfed conditions in five different locations. A known cultivar (Sham-1) was grown alongside the samples in all locations as a control. Test weight, 1000-kernel weight, the degree of vitreousness, protein content, starch content, amylose content and starch pasting properties were determined for the samples. The effect of the environmental factors and their interaction (site 9 irrigation) showed that the irrigation factor was more responsible for physical quality variations than the site factor (for instance, site variation of the irrigated conditions was responsible for 61% of the total quality variation and 34% of total quality variations in the rainfed conditions). Starch composition was influenced more by site variations than irrigation, whereas cultivar factor mainly influenced starch quantity, chemical composition and pasting properties (for instance, variations were mostly affected by cultivar (63%) more than site (15%) in the irrigated lands). The interaction of cultivar and site demonstrated significant effects on the degree of vitreousness, amylose content and starch pasting properties. International Journal of Food Science and Technology 2012 65 70 Starch -% Figure 1 Diagrams of the physiochemical characteristics of durum wheat samples grown under either rainfed or irrigated field condition at five sites.