Submitted to: Journal of Food Processing and Preservation
Publication Type: Peer Reviewed Journal
Publication Acceptance Date: August 26, 2011
Publication Date: February 21, 2012
Citation: Felker, F.C., Singh, M., Fanta, G.F. 2012. Effect of gluten on soybean oil droplets in jet-cooked starch-oil composites. Journal of Food Processing and Preservation. DOI: 10.1111/j.1745-4549.2011.00635.x. Interpretive Summary: Starch-oil composites prepared by excess steam jet cooking have been developed as a platform technology for delivering microscopic oil droplets in a water-based cooked starch dispersion for many food and industrial applications. Composites made with wheat flour as the starch source behaved differently than typical cornstarch-oil composites. This study was undertaken to investigate interaction of oil droplets with gluten, the protein component of wheat flour, in jet-cooked starch-oil-gluten composites using microscopy and centrifugation techniques. Gluten reduced the size and eliminated the mobility of oil droplets, as the oil was trapped in dispersed gluten network fragments suspended in the starch dispersions. This allowed composites to hold more oil and allowed drum dried flakes to more efficiently encapsulate oil and reduce its ability to be expressed from drum dried flakes by compression. This discovery will broaden the range of starch/oil ratios possible in both liquid and dry starch-oil composites, and will benefit consumers by allowing producers to develop more nutritious flavor delivery and fat replacing food applications based on this technology.
Technical Abstract: Jet cooked starch-lipid composites have been developed as a technology for suspending micron-size lipid droplets in an aqueous cooked starch dispersion. Normally oil droplets are independent and freely mobile in such liquid composites. When wheat flour was used as the starch source, unusual behavior of the cooked dispersion was observed suggesting gluten effects on oil droplet distribution. This study was undertaken to characterize the interaction of gluten and soy oil droplets by jet cooking individual flour components and combinations and determining the effect of added gluten in a model system of cornstarch-soy oil composites.