Effects of Rigor State, Salt Level and Storage Time on Chemical and Sensory Traits of Frozen and Freeze-Dried Ground Beef

Abstract

Both pre- and post-rigor beef semimembranosus muscles were ground with salt (0, 2 and 4%) and then subdivided into two treatment groups (freezing and freeze drying) and evaluated during storage of 0, 5, 10 and 15 wk for chemical and sensory traits. Rehydration ratios of pre-rigor freeze-dried beef (salted or unsalted) were not significantly changed during a 15-wk storage period at 25°C. With the addition of 2 and 4% salt, pre-rigor freeze-dried beef was less susceptible (P<0.05) to lipid oxidation (lower TBA values) than post-rigor, freeze-dried beef. Pre-rigor, freeze-dried beef was superior to post-rigor, freeze-dried meat in all sensory traits studied. Differences in TBA values were not significant between pre-rigor and post-rigor, frozen beef treatments at any salt level (0, 2 and 4%). Pre-rigor, frozen beef samples were superior (P<0.05) to conventional post-rigor, frozen meat in panel tenderness and acceptability scores. The TBA values of pre- and post-rigor beef (frozen or freeze dried), in general, increased with increased salt level (0, 2 and 4%). Freeze-dried beef samples (pre- or post-rigor) were less (P<0.05) tender, cohesive, acceptable and more rancid and/or off-flavor than frozen meat (pre- or post-rigor).