Characteristics of fat and muscle from beef heifers offered a grass silage or concentrate-based finishing ration

Abstract

The effect of the diet offered to heifer progeny of a grassland-based spring calving suckler beef production system during the finishing period on the colour of carcass fat and the colour and sensory characteristics of longissimus thoracis et lumborum muscle was determined in the context of suitability for one sector of the Italian beef market. A diet based on grass silage plus concentrate was compared with a diet based on concentrates and wheat straw. Compared to animals offered the concentrate-based diet both the kidney/channel fat and subcutaneous fat from animals offered the grass silage based diet was more yellow and a greater proportion (33 v 0%) were deemed unacceptable for this market on the basis of fat colour. There was no effect of diet on muscle colour or on muscle pH, drip loss, taste panel traits or shear force values or on market acceptability based on muscle colour. The maximum level of dietary inclusion of grass silage to avoid inadequate fat colour remains to be determined.