MODELING MEAT FREEZING

The effects of frozen storage on rancidity, color and selected textural properties (drip loss, cooking loss and shear strength) of ground beef patties was studied. The parameters included storage temperatures of (-12.2, -23.3 or -34.4 C), fat levels (15 or 30%) and packaged in polyvinyl chloride vacuum packaged or polyethylene overwrap. The samples were analyzed for rancidity, and textural and color degradation at 4 wk intervals for a period of 20 weeks. The effect of the independent variables were observed and the most significant parameters identified. Time-temperature effects as a function of fat levels and package type are presented in the form of response surfaces. Additionally, a finite difference model was developed to predict transient temperature response during freezing and thawing of food-stuffs. The model was tested against slab-shaped ground beef patties. The model accounted for three different boundary conditions encountered during freezing heat transfer as well as variable thermophysical properties below the initial freezing point