Relationship between protein markers and the sensory/physicochemical parameters of ovine meat during refrigerated storage

Description of the subject. Commercialization requires the storage of meat for a period of time according to the distribution and supply chain, usually under refrigeration and vacuum packaging. During this stage, many biochemical reactions can modify the sensory and physicochemical properties of meat. Proteolysis is one of the most important of these reactions as proteins are the building blocks of muscle, and their degradation affects tenderness. Objectives. The objectives of this study were to use multiple factorial analyses to correlate the physicochemical, sensory, and proteolytic changes in ovine meat during refrigeration. Method. Each loin was separated and randomly assigned to day 3, 5, or 14. Sensory panel evaluated the meat for appearance, odor and texture parameters. Warner-Bratzler shear force and texture profile analysis were evaluated. Similarly, protease activity was evaluated. Samples for 2D-electrophoresis and western blotting were collected at days 3, 5, and 14 post mortem. The results were analyzed by multiple factorial analyses. Results. The relative protein levels of desmin, vinculin, and myosin were found to decrease with time. Multiple factor analysis showed that the Warner-Bratzler shear force (WBSF) was highly correlated with the relative desmin concentration, the relative vinculin concentration, and acidic protease activity. The activities of acidic and neutral proteases were positively correlated with myosin level on day 3, but were negatively correlated with manual tenderness and myosin level on days 5 and 14. Conclusions. Therefore, desmin, myosin and vinculin, which correlate with sensory and physicochemical parameters during refrigerated storage, may prove useful as markers for tenderness.