Project Number: 5325-41000-050-00
Project Type: Appropriated

Start Date: Jan 11, 2005
End Date: Nov 30, 2009

Objective:
Isolate and characterize biologically active constituents in grains, legumes, nuts and vegetables, and their co-products. Optimize processing and storage conditions to enhance flavor and health-promoting phytonutrients. Add value to grains, legumes, and/or vegetables by extrusion technology using processing parameters and texture-modifying ingredients to control or enhance nutritional, textural and sensory properties.

Approach:
Extrusion processing will be used to produce new value-added foods with enhanced nutritional and sensory properties. Extrusion operational parameters such as moisture content, temperature, feed rate, screw speed and screw element configuration will be optimized. Ingredients from corn, rice, potato, tapioca and apple will be added to legume flours to enhance the physiochemical properties of the extruded products. To understand the influence of processing on flavor, phytonutrients and antioxidant activity, qualitative and quantitative studies will be performed on the agricultural products before and after processing. Impact flavor constituents will be localized, characterized and quantified using aroma extract dilution analysis (AEDA), gas chromatography-mass spectrometry (GC-MS), calculation of odor units, and preparation of aroma models. Biosynthetic precursors of aroma compounds such as glycosides will be identified and model systems will be used to explore precursors of some aroma compounds formed during processing. The investigators will develop and apply capillary electrochromatography (CEC) to rapidly and efficiently characterize phytonutrients such as carotenoids in foods. Phytonutrients will be separated, characterized and quantified using HPLC-DAD, HPLC-MS and proton and carbon NMR spectroscopy. Antioxidant activity will be measured by the ability of extracts of specific constituents to scavenge the free radical DPPH and the ability to inhibit the oxidation of methyl linoleate and hexanal. Replaces 5325-41000-042-00D (12/04).