Tomasz Żmijewski

The composition and properties of beaver (Castor fiber) meat

We analyzed the meat composition of ten females and seven males of sexually mature European beavers (Castor fiber L.). Cutting yield, percentage of particular elements, and chemical composition of the meat were determined. On average, a beaver carcass constitutes 48.6% of beaver body mass and contains 62.8% of meat, 14.5% of fat and 22.4% of bones. The thigh was found to be the largest and most valuable element constituting 33.4% of carcass weight and containing 66.7% of meat. Beaver meat has a high concentration of protein (20.9–21.8% wet wt.) and minerals (1.27–1.31%). The fat was characterized by a high proportion of polyunsaturated fatty acids (48.0–53.1%).

Effects of aging treatment and freezing/thawing methods on the quality attributes of beef from Limousin × Holstein-Friesian and Hereford × Holstein-Friesian crossbreeds

The objective was to investigate combined effects of aging-, freezing-, thawing- treatments on the water-holding capacity, Warner-Bratzler shear force (WBSF) and sensory properties of beef. Semitendinosus muscles from two crossbreeds were analysed. Carcasses were conventionally aged (4days post mortem), muscles were separated and divided into samples. Part of the samples were frozen without wet-aging and the others were wet-aged for 3 or 6days (and then also frozen). Two freezing methods (conventional and cryogenic) and two thawing methods (at 4°C and 20°C) were applied. Stepwise conventional/wet-aging just as thawing at 20°C, decreased the WBSF (P<0.05) and increased the scores for tenderness (P<0.05). Moreover, wet-aging for 3days gave an equal effect on tenderness (P>0.05) as the 6-days period. Meat from Hereford-crosses scored significantly higher for juiciness, compared with Limousin-crosses. These tips may be applied in the meat industry to reduce time of aging process and ensure a consistent high quality of frozen beef.