Effects of high hydrostatic pressure-thawing on pork meat

Frozen pork meat was thawed under high pressure (100-500 MPa) and physicochemical and histological parameters (thawing loss, tenderness, color, drip, ultrastructure, etc.) were compared with those of meat thawed by running water. Effects on physicochemical properties. The meat drip decreased by high hydrostatic prcssure-thawing, and the water holding capacity of the meat improved. The discoloration of the meat induced by high pressure-thawing was not recognized with the naked eyes up to the pressurization of 200 MPa. The meat tenderization was induced during high pressure-thawing. When the frozen pork was pressurized at 200 MPa, the most desirable results were obtained. However, the changes caused by high pressure-thawing over 200 MPa were not favorable. Effects on ultrastructure and myofibrillar proteins. The regular structure of myofibrils was gradually lost with the increase of the pressure applied, and the remarkable changes were observed in the meat thawed by pressure above 200 MPa. The measurements of the size distribution of the myofibrils prepared from high pressure-thawed meats indicated that frequency of distribution centered on a certain point with the increase of the pressure applied, in different from the progress of the fragmentation as observed in the myofibrils prepared from pressurized meats. The SDS-PAGE analysis showed the progressive solubilisation of alpha-actinin, troponin T, tropomyosin, and myosin light chain (MLC) in the meat thawed by pressure above 200 MPa.