Study On The Wheat Kernel Quality And Its Utilization In District Level

Wheat kernel quality, the main economic character of wheat varieties and the standard of wheat quality evaluation and marketing price in international trade, is closely related to the processing characteristics. The kernel quality for wheat from different areas and years was different as it was significantly influenced by types and quality of wheat varieties, environmental conditions and cultivated measures. There have been many studies on wheat kernel quality and its influencing factors and many consistent conclusions have been obtained based on the design of field experiments. These works have played a positive role on improving wheat yield and quality. In this study we analyzed the variety composition and quality traits of wheat collected from farmer fields and grain depots in the north of Henan province—one part of Huang-Huai Winter Wheat Zone. We also evaluated processing characteristics of these wheat samples and studied factors affecting wheat quality. The objectives of our research were to evaluate wheat quality and its application value in the food industry and to explore the main factors limiting wheat quality.A total of 243 farmer field wheat samples and 79 grain depot wheat samples were collected at the fixed locations in the north of Henan province from 2008 to 2010. The variety composition, wheat kernel quality and dough rheological properties were analyzed to evaluate the application value of wheat in the food industry. Sources of variance and correlation among kernel quality properties of wheat samples from farmer fields were studied to explore the main factors affecting wheat kernel quality properties during growth and the differences of correlation among kernel quality properties of wheat samples from different populations and sources. The main conclusions drawn from this research were listed as follows:(1) The numbers of wheat varieties collected from farmer field in north of Henan province from 2008 to 2010 were 32, 25, 20, respectively. The proportions of the top five number of wheat samples to total wheat samples were 52%, 64%, 79%, respectively. The proportion of wheat samples—Aikang 58, Zhoumai 16 and Xinong 979—to total wheat samples from farmer field was 53.1%. It indicated that theses three wheat varieties were the main cultivars in the north of Henan province. In general, the number of wheat varieties was decreasing gradually by year, and the varieties have a central tendency.(2) The average yield of 60 wheat samples from farmer field in the north of Henan province and central of Hebei province was 506 kg/mu, and the highest yield was 739kg/mu. There was a marked variation (450kg/mu) among yield of wheat samples at different locations. It indicated that the grain yield level of wheat varieties from farmer field was high, and it could be increased further more.(3) For the wheat samples from farmer field in the north of Henan province between 2008 and 2010, the thousand kernel weight, test weight, kernel hardness, protein content, wet gluten content and dough stability were 43.1g, 807g/L, 57%, 13.8%, 28.4% and 8.6min respectively. For the wheat samples from grain depot, the test weight, protein content, wet gluten content and dough stability were 805g/L, 13.6%, 27.6% and 5.6min respectively. Field surveys showed that 33.3% of farmer field wheat samples and 10.1% of grain depot wheat samples met the national standard of strong-gluten wheat with dough stability≥7.0min being the evaluation standard. However, only 4.5% of farmer field wheat samples met the national standard of strong-gluten wheat with test weight≥770g/L, protein content≥14.0%, wet gluten content≥32% and stability≥7.0min being the evaluation standards together, while the proportion of wheat samples from grain depot was zero. Low wet gluten content, short dough stability and inharmonious wheat kernel quality properties were the main reasons for the low proportion of high-quality and strong-gluten wheat products.Over all, it indicated that the north of Henan province was the area that could produce wheat products with hard kernel, high protein and medial-strong gluten. It was promising to grow strong-gluten wheat in this area.(4) Except for wet gluten content, all quality properties of wheat varieties appeared to be predominantly controlled by genetic effects. with contribution rate more than 50%. For factors such as test weight, grain hardness, flour extraction, falling number, zeleny-sedimentation volume, gluten index, dough development time, stability, degree of softening, farinograph quality number, extensibility, resistance, maximum resistance and energy, cultivar accounted for over 50% of total variance. For factors such as zeleny-sedimentation volume, dough development time, stability, farinograph quality number, extensibility, maximum resistance and energy, cultivar accounted for over 75% of total variance. Thousand kernel weight protein content, wet gluten content and farinograph absorption were mainly influenced by the environmental effects accounting for 40.2%, 45.8%, 58.0% and 48.9% of the total variance, respectively. Test weight, flour extraction, falling number and extensibility were significantly influenced by the climatic factors accounting for 12.9%, 6.4%, 1.2% and 9.2% of the total variance , respectively. The fertilizer rate was the main reason influencing protein content, zeleny-sedimentation volume, wet gluten content and extensibility and explained 8.3%, 0.7%, 15.2% and 1.2% of the total variance for those factors respectively.Thus, the processing properties of wheat varieties were mainly influenced by genotypic effects, and the protein properties (content) were mainly influenced by environmental effects, especially soil fertility.(5) There were positive correlations between zeleny-sedimentation volume and dough stability, between dough stability and maximum resistance, and this correlation will not be changed with the interannual variation as well as the variation of populations, sources.(6)The main objective was to enhance the zeleny-sedimentation volume, stability and resistance of wheat varieties. The level of cultivated measures now could meet the requirement of enhancing the content of wheat protein and wet gluten.