Comparison of thermal gelation properties of pork, beef, fish, chicken and turkey

Postrigor semimembranosus muscles of pork and beef, chicken breast (CB), chicken thigh (CT), turkey breast (TB), turkey thigh (TT), and catfish fillets were obtained. Gelation properties of muscle (10% protein at pH 5.5, 6.0, 6.5, or 7.0 and cooked at 0.7$\sp\circ$C or 3$\sp\circ$C/min to 70$\sp\circ$C) and myofibril (5, 7, or 10% protein at pH 6.0 and cooked at 0.7$\sp\circ$C/min to 70$\sp\circ$C) of all species were evaluated. Myofibril (MF), sarcoplasmic protein (SP), connective tissue (CTS), myosin and actin from Pork and CB were purified. Gelation properties of MF, SP, CTS, MF + SP, MF + SP + CTS, and muscle (7, or 10% protein at pH 6.0) from both pork and CB were compared. Gelation properties of normal and DFD (dark, firm and dry) pork semimembranosus muscles (10% protein at pH 5.5, 6.0, 6.5, or 7.0), and stretched and cold shortened bovine sternomandibularis muscles (10% protein at pH 6.0) and myofibrils (8% protein at pH 6.0) were evaluated.CB and CT muscles had the highest gel strength (GS) and lowest cooking loss (CL) for both slow and fast heating rates at pH $>$ 6.0, while TB had the lowest GS. Muscles of pork, beef, fish and TT had the highest GS at pH 6.0 for both heating rates. CL of all the muscles decreased as pH increased. Myofibrils from CB and CT had the highest GS and lowest CL, while fish myofibrils had the lowest GS and highest CL. Pork and beef myofibrils had intermediate values. Pork myosin had higher GS and lower CL than CB myosin. Actin did not form measurable gel in either species. Myosin and actin mixture (2:1) had lower GS and higher CL than myosin alone. There was no difference in GS between muscle and MF + SP + CTS at 7% protein for both pork and CB. MF produced higher GS and lower CL while CTS and SP had higher CL than all other gels. CTS contributed to gel firmness. Muscle with high initial pH (DFD) had higher GS and lower CL at all adjusted pHs than normal muscle. Stretched muscle sarcomeres were longer than those of cold shortened muscle. Myofibrils of stretched muscle had higher GS and lower CL than myofibrils from cold shortened muscle.U of I OnlyETDs are only available to UIUC Users without author permissio