Dynamic mechanical analysis of marinated chicken breast meat

Chicken breast muscle was marinated and tumbled in solutions of 7% NaCl and 1.2% of disodium pyrophosphate (DSPP), tetrasodium pyrophosphate (TSPP), t etrapotassium pyrophosphate (TKPP), sodium tripolyphosphate (STPP), or glas s phosphate. Dynamic mechanical thermal analysis was used to measure storag e modulus and Tan delta as samples were heated from 25 to 75C. For untreate d samples, four thermal transitions were noted with the most significant tr ansition at 55.8C. Addition of NaCl and phosphate reduced the number of dis tinct events, and decreased the major transition to temperatures around 46- 48C. Uncooked, marinated samples had lower G' and Tan delta. Treated sample s also showed an increase in G' over the 25-45C range. Heating caused the g reatest changes in treated samples, with values of G'(75C) and Tan delta (7 5C) similar to untreated samples. Different phosphate types resulted in sig nificant differences in G' and Tan delta values. G' values correlated well with Young's modulus, but not with Warner-Bratzler shear values or expressi ble moisture. Results are discussed in terms of changes in muscle proteins resulting from exposure to NaCl and phosphates, as well as to heat.