Youssef, M. K., and S. Barbut,
"Effects of protein level and fat/oil on emulsion stability, texture, microstructure and color of meat batters",
Meat science, vol. 82, no. 2: Elsevier, pp. 228–233, 2009.
AbstractBeef meat batters formulated with increasing protein level (10–15%) and containing 25% beef fat were compared to batters prepared with 25% canola oil. Emulsion stability of the canola oil treatments was higher (less separation during cooking) at the 10–13% protein level compared to the beef fat treatments. However, above 13% protein this was reversed and the canola oil treatments showed high fat and liquid separation, which did not occur at all in the beef fat treatments. This indicates differences in stabilization of fat versus oil in such meat emulsions. Hardness of the cooked meat batters showed significantly (P < 0.05) higher values when the protein level was raised, and was higher in canola oil than in beef fat meat emulsions at similar protein levels. Products’ chewiness were higher in the canola oil treatments compared to the beef fat emulsions. Lightness decreased and redness increased in canola oil batters as the protein level was raised. The micrographs revealed the formation of larger fat globules in the beef fat emulsions compared to the canola oil meat emulsions. The canola oil treatment with 14% protein started to show fat globule coalescence, which could be related to the reduced emulsion stability.
Youssef, M. K., Q. Wang, S. W. Cui, and S. Barbut,
"Purification and partial physicochemical characteristics of protein free fenugreek gums",
Food Hydrocolloids, vol. 23, no. 8: Elsevier, pp. 2049–2053, 2009.
AbstractCrude fenugreek gum (3.74% protein) was purified by dissolving in aqueous solvent and centrifugation to remove impurities which yielded a purified gum fraction containing 1.10% protein residue. Further purification of the gum was achieved by treating the gum solution with phenol to obtain protein free fenugreek gum (0.16% protein residue). The three types of fenugreek gums were evaluated for: molecular weight, surface activity and rheological performance. Surface and interfacial tension, measured by a Du Nouy ring, indicated that the removal of protein in the gum significantly reduced its surface activity. However, the crude fenugreek gum exhibited lower intrinsic viscosity and radius of gyration compared to the purified and protein free fenugreek gums. It was found that both protein residue and gum concentration affected the elastic modulus (G′), viscous modulus (G″), and complex viscosity (η∗).