Effects of carrageenan on thermal stability of proteins from chicken thigh and breast muscles

Thermal stability of ground chicken meat and myofibrillar proteins mixed with kappa-, iota-. acid lambda -carrageenan (CGN) at different NaCl concentrations was investigated with differential scanning calorimetry. Three transitions, characteristic of myosin head (63.3, 62.2 degreesC), sarcoplasmic proteins/myosin tail (67.7, 68.6 degreesC), and actin (78.3. 81.4 degreesC), were observed for nontreated thigh and breast muscles, respectively. The influence of CGNs on the thermal transitions was dependent on salt concentrations. kappa -CGN with 2.5% NaCl decreased (P < 0.05) transition temperature (T-max) of thigh myosin head and actin, while all three CGNs with or without 2.5% salt decreased (P < 0.05) T-max for breast actin. Total enthalpy of denaturation decreased slightly in the presence of kappa -CGN for thigh muscles only. The gum effects on myofibril isolates were variable and were salt-dependent. The results suggested molecular interactions between the gums and meat proteins, but the response of the specific proteins to gums appeared to be muscle type dependent. (C) 2001 Elsevier Science Ltd. All rights reserved.