Thermal Gelation of Duck Breast and Leg Muscle Proteins

Abstract

Gels were made by heating duck breast and leg myofibrillar protein suspensions (20 mg/ml; pH 5.50, 5.75 and 6.00) at a constant rate of 1C/min from 18C to 70C. After heating the suspensions to 70C at pH 5.50, breast proteins formed gels which were not different (p > 0.05) in strength from leg proteins. At pH 5.75 and 6.00, however, breast proteins formed significantly stronger gels than leg proteins. Increasing the protein suspension pH from 5.50 to 5.75 had no significant effect on the strength of leg protein gels, whereas the strength of breast protein gels more than doubled. A further increase in pH from 5.75 to 6.00 resulted in a three‐fold decrease in the strength of leg protein gels; no significant difference was observed for breast gels. Overall, pH 5.75 was suitable for forming strong breast and leg protein gels, whereas pH 5.50 and 6.00 were detrimental for gel formation of breast and leg proteins, respectively. Variations in the gelation behavior of duck breast versus leg protein gelation are characteristic of differences in fiber composition of the muscle types.

Gelation of chicken breast and thigh muscle homogenates: Effect of pH and time of aging

“…At low protein concentrations different optima for gelation of chicken leg (ph 5.1/5.9) and breast (pH 5.4/5.6) myosin [3,25], and chicken/hen leg (pH 5.5) and breast (pH 6.0) myofibrils [31,32] have been observed. In addition, duck breast and leg muscle myofibrillar protein suspensions formed the strongest gels at pH 5.75 [26] and turkey white and red salt-soluble proteins had a maximum gel rigidity at pH 6.0 [8]. However, at high protein concentrations, the optimum pH for turkey breast and thigh myofibrils (8% protein) gelation [16] and comminuted turkey muscles (13/14% protein) gelation [4,7] was shifted to higher values (pH 6.4/6.5).…”