Available at: http://digitalcommons.calpoly.edu/theses/1648
Date of Award
MS in Agriculture - Dairy Products Technology
Philip S. Tong
Caseinate powders have been well accepted because of their foaming properties. In this study, 10% solution of reconstituted skim milk powder (SMP) chelated with sodium hexametaphosphate (SHMP) and trisodium citrate (TSC) at 1 mEq, 50 mEq, and 100 mEq were prepared to conduct a comparison with sodium caseinate, potassium caseinate, and calcium caseinate solutions. Foamability, foam stability as well as the preferential locations of αs-casein, β-casein and !-casein in their foams were analyzed. It was hypothesized that the foamability, foam stability and the preferential locations of these three caseins in the milk foams are different from treatment to treatment. Milk foam was generated with an air- injection method at a flow rate of 0.30 L/M for 18 seconds. Foam stability was measured through half-life method. The foam composition was quantified with sodium dodecyl sulfate-polyacrylamide gel electrophoresis (SDS-PAGE) method. Analysis of Variance (ANOVA) test results concluded that there were no significant differences detected in foamability (p>0.05). On the other hand, foam stability differed significantly among the treatments. Foams of reconstituted SMP-treated with 1 mEq SHMP and TSC were significantly more stable compared to other treatments (p < 0.05), β-casein (p>0.05) and !-casein (p>0.05). In conclusion, the addition of calcium chelating salts might increase the foamability to the same level as caseinate solutions. Furthermore, the study proved that the combination of calcium chelating salts and chelator levels is able to alter the foam stability.