High hydrostatic pressure treatment of minced beef for patty manufacture: effects of pressure level and holding time on thermal and molecular characterization of proteins

ECCOñA SOTA AMPARO; VAUDAGNA SERGIO R.; SPERONI FRANCISCO

Columbus, Ohio

Workshop; 2014 International Nonthermal Food Processing Workshop; 2014

Ohio State University

Several authors studied the application of high hydrostatic pressure (HHP), before or after the manufacture of low sodium content meat products. However, the effects of HHP treatment of raw material for patty manufacture, on the thermal behavior and molecular characteristics of proteins from patties are still not well understood. The aim of this study was to apply HHP on minced beef for patty manufacture, analyzing the effect of pressure level (150-300 MPa) and holding time (1-5 min) on thermal and molecular characterization of proteins from minced beef and patties. Patty composition: lean beef 78.75%(w/w), fat 10%(w/w), water 10%(w/w), NaCl 1%(w/w), Sodium-tripolyphosphate 0.25%(w/w). Thermal behavior and molecular characterization were carried out by DSC and SDS-PAGE. HHP treatment at 300 MPa denatured proteins from minced beef (denaturation degrees of total proteins were 43 and 56% for 1 and 5 min, respectively). The effect of holding time was confirmed for actin: partially (1 min) or completely denatured (5 min). The electrophoretic profiles from 300 MPa-5 min samples showed a decrease in intensity of bands of MHC, actin and 97 kDa and an increase in two bands of ca. 144 and 155 kDa. A similar behavior was found at 300 MPa-1 min, but with no decrease in actin band intensity. DSC analysis of patties showed a decrease in ÄH due to manufacture and/or additives, this denaturation was evident in sarcoplasmic proteins and/or myosin rod. The electrophoretic profiles of proteins from patties showed that the additives modified some effects on bands, e.g. the intensity of actin band was less decreased and those of the bands at 144 and 155 kDa less increased. These results indicate that HHP at 300 MPa on raw material promoted protein aggregation and that the aggregates in which actin was involved were solubilized by additives. This behavior suggests that actin was aggregated trough weaker and/or fewer interactions than myosin.