The nutrient composition of South African lamb (A2 grade)

Abstract

Dorper and Merino lamb carcasses of the A age group with a fat code 2 (±7% SCF) from three main production areas in South Africa were used for this study. The right sides of the carcasses were used to determine the raw nutrient and physical (carcass) composition of each cut as well as for the whole carcass by calculation. Three cuts (shoulder, loin and leg) from the left side were cooked in order to determine the nutrient composition thereof. Nutrients showing the greatest differences between raw and cooked treatments, were protein, total fat, C16:0 saturated fatty acid (SFA) and C18:1n9c monounsaturated fatty acid (MUFA). Moisture losses due to cooking resulted in an increase in the protein and cholesterol concentrations of the cooked cuts. Iron content was lower in the cooked loin cut but increased in the cooked leg cut when compared to the corresponding raw cuts. The vitamin B content of all three cooked lamb cuts was lower, although not significantly so, than that of the corresponding raw cuts. Lamb is a good source of protein, iron and the B vitamins, especially vitamin B 12 when cooked.

The influence of fat score and fat trimming on primal cut composition of South African lamb

“…He did, however, admit that the amount of untrimmed fat (mostly seam fat), increased with increase in fat score. Considering the ratios of intermuscular fat to SCF of retail cuts of a fat score 2 carcass (Table 7; Van Heerden et al, 2007), the total fat of shoulder, leg and loin cuts will be ~7, 12 and 29%, respectively (calculated from Table 6). If these cuts were trimmed to SCF levels equal to fat score 1, the remaining fat will be ~4, 7 and 13 %, respectively.…”

“…For the purpose of benchmark values, deboning data including SCF and IMF proportions of different cuts of the lamb carcass with a fat score of 2 were obtained from the study of Van Heerden et al (2007).…”

“…These cuts comply with Australian national heart foundation guidelines with a fat content <10%. With regard to the South African market, Van Heerden et al (2007) showed that even though South African lamb and mutton are mainly produced and sold relatively lean, certain cuts even in leaner fat classes have too much fat according [Just Lamb (www.justlamb.co.za) and natLAM (www.lawmeat.co.za)] have altered at least a part of their operations to boneless retail cuts, although fatness is still mostly controlled by restriction of carcass fatness during production. Adjusting these operations to trim excess fat will not only result in a more acceptable product, but will also enable processors to use carcasses of various fat classes, thereby increasing the supply.…”

Fish Oil Supplement Research Remains Murky

“…The animal (genetics), nutrition (grain-fed or pasture-grazed), meat cut and fat trimming influence the total fat content of beef and mutton portions (Schönfeldt and Welgemoed, 1996;Droulez et al, 2006;Scollan et al, 2006;Van Heerden et al, 2007). In beef, the fat is present as membrane fat (phospholipids), intermuscular fat and as subcutaneous fat, while marbling refers to the adipose tissue between the bundles of muscle fibres (Scollan et al, 2006).…”

Food composition data in health communication

“…According to the 1999 edition of the Composition of South African Foods, the fat content of lamb was listed as 21.6% (Sayed et al, 1999), but these data were derived from the United States Department of Agriculture Food Composition Database, which has since been updated. Recent studies on the most commonly consumed South African lamb and mutton cuts reported fat values of o10% on an average (Van Heerden et al, 2007).…”