Meat production traits of Angora goats. 2. Meat quality characteristics and fatty acid composition of meat from intact and castrated kids

Abstract

Context In Turkey, meat production contributes much more income than mohair production in Angora goat farming. Castration is expected to alter the meat quality depending on the slaughter weight. Aims This study was designed to determine the quality characteristics and fatty acid composition of meat from intact and castrated male Angora goat kids slaughtered at different liveweights. Methods Forty-eight single male Angora goat kids (24 intact, 24 castrated) were slaughtered at three slaughter weights (20, 25 and 30 kg) after being fattened intensively. Response variables were meat physical quality characteristics, chemical composition, total cholesterol and fatty acid profile. Data were subjected to analysis of variance using the general linear model procedure. Key results Colour parameters (L*, a*, b*, C* and H*), pH, water-holding capacity and cooking loss were significantly (P < 0.001) influenced by time post-slaughter. Castration did not affect (P > 0.05) these properties. L* values decreased (P < 0.001) as slaughter weight increased. With increasing slaughter weight, meat expressed less water and cooking losses were higher (P < 0.001). Warner–Bratzler shear force increased (P < 0.05) with slaughter weight. Castration affected meat chemical composition: moisture percentage decreased (P < 0.001), and protein and fat increased (P < 0.01). Similarly, protein and fat contents of the meat increased and moisture decreased with increasing slaughter weight (P < 0.001). With increasing slaughter weight, intramuscular fat of the longissimus thoracis muscle showed increased polyunsaturated fatty acids (P < 0.01) and ratios of polyunsaturated/saturated fatty acids (P < 0.001) and n-6/n-3 (P < 0.05), and decreased thrombogenic and atherogenic indexes (P < 0.001). Total unsaturated/saturated fatty acid ratio was higher and atherogenic index lower following castration (P < 0.05). Conclusions Castration of Angora male kids did not affect meat quality, but increased protein and intramuscular fat content of the longissimus thoracis muscle. Increasing slaughter weight positively influenced fatty acid composition pertinent to human health, but some measures indicated poorer meat quality. Implications Castration and slaughter weight did not greatly affect meat quality except for improvements in fatty acid percentages.