| Improvement of quality which includes two parts as nutrition and industry, is one of the major wheat breeding objectives in China. Most of the research has been focused on protein content, protein and starch quality, as well as their relationship with pan bread, steamed bread, noodles, and cakes, whereas little attention was given to improving the nutrition quality, and no information is available about phytochemicals including phenolics associated with metabolic syndrome. Wheat grain consumption helps to lower the incidence of cardiovascular disease and cancer related deaths through multifacrorial physiologic mechanisms including antioxidant activity, mediation of hormones, enhancement of the immune system, and facilitation of substance transit through the digestive tract. The objectives of this paper, which includes two parts, were to determine phenolic acid profiles of leading cultivars from the Yellow and Huai River Valleys Winter Wheat Region using high-performance liquid chromatograph, and to analysis milling effect on phenlic acid concentrations, to provide information for breeding for phenolic acid related quality.1.Phenolic acid concentration was determined in 37 Chinese commercial winter wheat cultivars grown at a single site over two seasons, and the fractions comprising free and bound types were analyzed using HPLC with measurements for individual phenolic acids. Most of the parameters were significantly influenced by cultivar, season, and their interaction effects, with cultivar variance being predominant. Wide ranges of variation among the 37 cultivars were observed for the concentrations. The average concentration of bound type was 661μg/g of dm, making up 97.5% of the total phenolic acid with ferulic accounted for 70.7% of the concentration, while free type made up only 2.5% of the total phenolic acid with syringic accounted for 44.7% of the concentration. Highly significant and positive correlations between bound phenolic acid components as ferulic, caffeic, chlorogenic, vanillic, p-coumaric, and gentisic concentrations and the corresponding total phenolic acid components were found, as well as the correlations between bound and total phenolic acid concentration, indicating the predominant contribution of bound type to the total phenolic acid concentration. In comparision, Liangxing 66 and Zhongmai 895 were more stable in concentration of the components in phenolic acids across seasons, with high value of free and bound phenolic acid, and could be selected for production and as parents in wheat breeding for health beneficial phenolic acid.2.High performance liquid chromatograph was used to determine the distribution of phenolic acids in wheat flours with five extraction rates ranging from 60% to 100% in four cultivars sown in two locations in 2008–2009 season. The phenolic acids and the components were all significantly influenced by the effects of cultivar, milling, location, and cultivar by milling interaction, with milling having the dominant effect. It also indicated that the proportions of phenolic compounds varied a lot among milling fractions and cultivars, and the levels of phenolic acids depend both on initial grain concentrations and on selection of the milling fraction that is incorporated into the final product. The total phenolic acid concentrations ranged from 54μg/g in flour with 60% extraction rate to 695μg/g in flour with 100% extraction rate, indicating the concentration of phenolic acid in the outer layers. Therefore, wholemill wheat products can maximize health benefits and are strongly recommended to be used for food processing. |
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