Submitted to: Journal of Food Processing and Preservation
Publication Type: Peer Reviewed Journal
Publication Acceptance Date: 3/25/2013
Publication Date: 8/1/2014
Publication URL: http://handle.nal.usda.gov/10113/60493
Citation: Onwulata, C.I., Tunick, M.H., Thomas-Gahring, A.E. 2014. Pasting and extrusion properties of mixed carbohydrates and whey protein isolate matrices. Journal of Food Processing and Preservation. 38(4):1577-1591. DOI: 10.1111/jfpp.12118.
Interpretive Summary: Mixing different types of food proteins may improve binding, flavor or mouthfeel of foods such as yogurt or lunch meats. The problem is that different types of proteins do not mix well when added to starch, and sometimes act against each other when used to make corn puffs. Our research showed that corn starch, barley, and plantain make good products with whey proteins. One type of whey protein custom-made with heat works best with corn. The source of the starch makes all the difference in how it mixes with whey proteins.
Technical Abstract: Mixed systems of whey protein isolate (WPI) or texturized WPI (tWPI) and different starches may form weak or strong gel pastes or rigid matrices depending on interactions. The paste viscoelasticity of starches from amioca, barley, corn starch, Hylon VII, plantain, and pea starch, mixed with whey protein isolate or textured WPI at the concentrations of 75/25, 50/50, or 25/75 wt% was determined using a Rapid Visco-Analyzer (RVA). Peak paste ranged from plantain (5.33 Pa.s), amioca (4.14 Pa.s), corn starch (3.65 Pa.s), barley (2.61 Pa.s), Hylon VII and pea starch (0.10 Pa.s). The presence of whey proteins reduced paste viscosity and extrusion expansion, but reduced hardness and improved fracturability. Moisture content was a stronger determinant of paste properties and of the denatured state of the whey protein isolate.