Location: Dairy and Functional Foods ResearchTitle: Flow behavior of mixed-protein incipient gels Author
Submitted to: International Journal of Food Properties
Publication Type: Peer Reviewed Journal
Publication Acceptance Date: 6/8/2012
Publication Date: 7/1/2014
Publication URL: http://handle.nal.usda.gov/10113/60540
Citation: Onwulata, C.I., Tunick, M.H., Mukhopadhyay, S. 2014. Flow behavior of mixed-protein incipient gels. International Journal of Food Properties. 17(6):1283-1302. Interpretive Summary: Milk proteins such as calcium caseinate, whey protein concentrates, and whey protein isolates are very useful as nutritious ingredients when added to different food products. A better understanding of how these proteins mix with each other or with other ingredients is needed. Our work showed that it is best to combine milk proteins with egg protein, fish protein, soy protein, or wheat protein to make foods with improved quality. Milk proteins can be mixed with egg proteins for better thickness.
Technical Abstract: Strong protein gel networks may result from synergistic interactions with other proteins or food materials above that achievable with a single protein alone. We determined varying flow and viscoelastic behavior of calcium caseinate (CC) or whey protein isolate (WPI) mixed with egg albumin (EA), fish protein isolate (FPI), soy protein isolate (SPI), or wheat gluten (WG) in a model system with wheat flour and glycerol as starch and oil surrogates. Temperature sweeps revealed peak tan d values as the proteins aggregated. Single protein gels of CC, SPI, and WG were predominantly elastic, while EA and WPI gels were mostly viscous. For example, EA steady shear viscosities were: 14.5 cP (0.5 min) and 133.1 cP (45 min), and WPI 0.3 cP/0.5 min and 2.4 cP/45 min; but combined with WPI (WPI/EA: 10/5 wt percent), the apparent viscosity values dropped to 5.3 cP/0.5 min and 22.1 cP/45 min, respectively.