The effects of pH, NaCl and CaCl2 on thermal denaturation characteristics of intramuscular connective tissue

The research was conducted with two different experiments on intramuscular connective tissue obtained from Longissimus dorsi muscle of 4-year-old beef carcasses. Differential scanning calorimetry (DSC) was used to determine the denaturation onset temperature (To), denaturation peak temperature (Tp), and denaturation enthalpy (ΔHD) of intramuscular connective tissue. In the first experiment, equilibration of the collagen in citrate buffers in the pH range 2.9–6.5 resulted in the decline of To and Tp with decreasing pH, but statistically significant differences were not recorded for ΔHD. In the second experiment, NaCl and CaCl2 solutions at 0.34, 0.68 and 1.02 ionic strength at pH 3.7–5.7 were studied. Increasing NaCl resulted in the increase of To and Tp, whilst To and Tp was decreased with increasing CaCl2.