High pressure processing of beef patties: effect on myofibrillar proteins and textural properties

SZERMAN, NATALIA; SPERONI, FRANCISCO; VAUDAGNA, SERGIO

Congreso; 57th ICoMST International Congress of Meat Science and Technology; 2011

High pressure processing (HPP) has been proposed as a possible mean for improving functional properties of proteins, since it induces protein denaturation, aggregation or gelation. The aim of this study was to evaluate the effects of HPP on myofibrillar beef proteins and their potential influence on textural properties of beef patties. Patties were elaborated with 80% beef meat, 10% water and 10% fat (A: no additives; B: 2% NaCl and 0.25% sodium tripolyphosphate). After freezing, A and B patties were submitted to 300MPa-5min (A300-5, B300-5) and A0 and B0 (non-pressurized) were kept frozen. Electrophoretic profiles of meat proteins extracted by 0.1M NaCl; 0.6M NaCl; 0.6M NaCl+0.8%SDS or 0.6M NaCl+0.8%SDS+5% 2-mercaptoethanol (100°C) were monitored by SDS-PAGE. Thermal behavior of meat proteins was studied by DSC. Texture profile analysis of grilled patties was performed. Extracted proteins with 0.6M NaCl+0.8%SDS+5% 2-mercaptoethanol from all treatments presented similar electrophoretic profiles. This result suggested that proteins, which could not be extracted by 0.6M NaCl or 0.6M NaCl+8%SDS, were involved in the formation of high pressure-induced aggregates stabilized by disulfide bonds. According to DSC, HPP caused total denaturation of actin and decrease in temperature denaturation of myosin, probably due to a structure modification. Addition of salts (B0) diminished denaturation temperature and enthalpy of myosin and actin, being this effect enhanced by HPP (B300-5). HPP increased all texture parameters for patties with (B) or without additives (A); excepting cohesiveness which did not present differences in B patties. HPP modified the binding between meat particles as a consequence of the enhancement of myofibrillar proteins aggregation.