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
FCMDL is a co-PI on a 4-year grant entitled “Whole Grains: Processing, Fiber, Color, and Phytonutrients” awarded to the Western Wheat Quality Lab and Washington State University by AFRI. The research to be conducted includes (1) determine the effects of product processing on fiber, phenolic composition, and antioxidant activity in two model foods, bread and pancakes, made from whole grain and white flour, (2) determine the genetic variation for fiber, phenolics, antioxidants, and color quality in wheat varieties across the U.S., and (3) understand the interactions of polyphenol oxidase, phenolics, and antioxidants in modifying fiber, phenolics, and food product color during processing. FCMDL’s responsibility is to develop methods for the extraction of phenolic compounds from the wheat and to determine the phenolic concentration in each ground wheat fraction. During the first year, we compared the phenolic acid composition and the antioxidant capacity of five spring wheat cultivars, ‘Alpowa’, ‘Blanca Grande’, ‘Louise’, ‘Macon’, and ‘Westbred 936’ that were field-grown in the eastern Washington state region in 2009. Alpowa and Louise are soft white cultivars, Blanca Grande and Macon are hard white cultivars, and Westbred 936 is a hard red cultivar. Druing this fiscal year, we carried out a comparison of three commonly used extraction solvent mixtures for optimizing extractions of soluble phenolics from grain samples. The effect of the number of extraction cycles and influence of different grinding methods on the yield of soluble and bound phenolics is currently being evaluated. This agreement was monitored through routine conversations, presentations, and email communications with the Principal investigator from the Western Wheat quality Lab, ARS, USDA, Pullman, WA.