1a. Objectives (from AD-416):
The overall research project has three objectives: 1) characterize the interactions of arabinoxylan fiber, phenolics, and antioxidants during processing, 2) develop analytical methods for phenolics and antioxidants, and 3) determine the physico-chemical characteristics of bioactive compounds (arabinoxylans, phenolics, and antioxidants) during processing. Objective 2 will be conducted at the Food Composition Methods Development Laboratory (FCMDL).
1b. Approach (from AD-416):
Samples provided by USDA-ARS Western Wheat Quality Laboratory will be initially used for optimization of sample preparation procedures for extraction of phenolic phytochemicals from wheat samples. Different cultivars of wheat samples will be used to collect spectral fingerprints and determine whether spectral fingerprinting methods can be used to differentiate wheat samples based on cultivar or other phytochemical traits.
3. Progress Report:
Phytochemical content in different fractions flour, dough, and bread (upper crust, central crumb, and bottom crust) have been analyzed in two wheat cultivars, ‘Louise’ (soft white) and ‘Macon’ (hard white). Ferulic acid, lutein, and a-tocopherol were the predominant phenolic acid, carotenoids, and tocopherol, respectively, extracted from all fractions. The quantities of the main components were significantly higher in all fractions made from whole wheat flour than quantities in fractions made from refined flour. The concentration of phenolic acids in the upper crust of refined bread of both wheat cultivars (Louise and Macon) was higher than the dough fraction. However, marginal reduction in the phenolic acids level were observed in upper crust of whole bread as compared to their respective dough fractions for both wheat cultivars (Louise and Macon) The dough had somewhat higher levels of tocopherols and carotenoids as compared to crumb and upper crust, suggesting some possible degradation of tocopherols and carotenoids during baking.