No abstract

No abstract

A comprehensive set of quality parameters has been recorded for meat and fat from groups of castrate and ram lambs raised on pasture and slaughtered in groups of six at 91-day intervals from 122 to 668 days of age. These include mechanical evaluation of meat tenderness, sensory evaluations of meat flavour and fat odour, and measurements of fat colour, fatty acid composition, vitamins C and E, free glucose and iron in the meat, and of the concentrations of the flavour compounds indoles, phenols, and branched chain fatty acids in the fat. There was significant variation in many parameters between slaughter days, including markedly lower meat tenderness in one slaughter group, probably in response to unfavourable pasture conditions. Older ram lambs tended to be less tender than castrates of the same age. However, no longer-term age-related trends were observed in tenderness or flavour quality. Concentrations of free glucose in rigor muscle and vitamin C showed a declining trend with age. A05063; Online publication date 25 October 2006 Received 29 November 2005; accepted 19 September 2006Concentrations of the branched chain fatty acids 4-methyloctanoic and 4-methylnonanoic acids in fat increased with age. Sex category effects were observed for the branched chain fatty acids and for indole and skatole. Higher concentrations were observed in ram lambs. The data indicate there is only a limited decline in lamb meat quality characteristics up to nearly 2 years of age, but that pasture feeding conditions may affect quality significantly.

No abstract

Available literature mainly describes the fatty acid (FA) content of raw meat, with only limited data explaining the effect of different preparation and cooking temperatures on health-promoting FA such as conjugated linoleic acid (CLA), its metabolic precursor trans-vaccenic acid (TVA), and long chain omega-3 FA (LC omega-3 FA). We collected m. longissimus thoracis (LT) from rib chops of Poll Dorset × East Friesian (EF) and Poll Dorset × Romney (R) lambs raised together. The FA composition of raw LT was compared with LT prepared with bone and all fat trimmed away or bone and fat left intact before cooking under a fan-grill. The LT from EF lambs had less cooking loss, lower lipid and total fatty acid (TFA) contents, and a lower proportion of saturated fatty acids (SATFA) than the LT from R lambs. Raising cooking temperature from medium to well-done increased cooking losses and dry matter (DM) yield but did not affect FA content or composition. Compared with raw LT, cooking of the trimmed LT resulted in more TFA and lipids in the DM, and these were greater still in the intact LT.