Project Number: 5430-44000-017-00
Project Type: Appropriated

Start Date: Oct 01, 2004
End Date: Sep 30, 2009

Objective:
Determine relationships between sorghum grain physical properties including hardness, diameter, and kernel weight, protein and starch composition and processing quality and identify sorghum biochemical components related to food functionality and bio-industrial uses such as ethanol production. Use knowledge of these components to improve the quality and yields of bio-industrial materials and the quality and functionality of sorghum flour which will facilitate development of new, high quality foods, especially for the gluten free food market.

Approach:
New slope and bias curves for measuring hardness, diameter, weight and moisture of sorghum grain by the SKCS will be determined for more accurate characterization of sorghum using the SKCS. Differences in protein content and composition of isolated hard and soft endosperm fractions will be determined. Sample sets to be used for relating processing quality to protein content and composition will be collected. Samples varying in pericarp color, presence of testa layer, plant color, and kernel attributes for analysis of grain color compounds, phenolics, and other small molecules will be collected. Techniques for extracting and analyzing sorghum color compounds by HPLC and HPLC-MS will be developed. Multi-instrument SKCS comparisons and calibrations with researchers in Kansas, Nebraska, and Texas will be completed. The effect of environment on protein content and composition of isolated hard and soft endosperm fractions will be determined. Wet milling, dry milling, extrusion and fermentation quality of selected sorghum lines will be conducted. Color compounds, phenolics, and other small molecules in sorghum from weathered and sound grain; evaluate grains for markers of insect and fungal damage and infestation will be characterized and cataloged. Exotic germplasm will be evaluated for desirable processing traits (e.g. ethanol yield). GxE stability of processing quality in sorghum lines showing desirable processing traits will be evaluated. Impact of compounds found in sorghum grains as a result of weathering, mold, insects, or fungal invasion on food and processing quality will be determined. Processing methods to reduce or eliminate impact of environmental damage will be investigated. Improved techniques for extracting and analyzing sorghum proteins will be developed. Methods for extracting and purifying sorghum proteins for industrial and food applications will be determined. Formulations for the production of wheat free sorghum foods from batter type systems will be optimized. Optimization of batter type product formulations for production of wheat free sorghum based foods will be continued. Visco-elastic dough formation in artificial sorghum protein-starch dough systems will be investigated and changes to sorghum proteins during mixing will be elucidated and compared to wheat proteins during mixing. Methods for disruption of sorghum protein bodies in sorghum flour to free proteins for interaction during mixing will be developed. Starch and protein content and composition from diverse sorghum lines will be determined and related to ethanol and lactic acid yields. The extent of protein-protein interaction and protein-starch interaction in artificial sorghum dough systems will be determined. Methods for the use of reduction-oxidation systems to form a visco-elastic dough directly from sorghum flour will be developed. Sorghum proteins and starch will be modified to improve functionality in food. Pre-treatment methods for altering protein and starch composition in sorghum for improved ethanol and lactic acid yields will be developed.