Pasture feeding improves the fatty acid composition of lamb muscle

Abstract

Background

The nutritional quality of red meat is an increasing priority for consumers. Grass-fed lamb is known to be higher in health-promoting omega-3 fatty acids (FAs), especially relative to concentrate feeding. Given advances in pasture management, concentrate formulation, and ruminant genetics, a further assessment of FA concentrations in lamb meat is warranted.

Methods

Three groups of lambs, from one research study (n = 26) and two commercial studies (n = 57), were used. Lambs were finished on a grass or concentrate diet. FAs of longissimus dorsi (LD; n = 83) and quadriceps femoris (QF; n = 83) were measured quantitatively using gas chromatography–flame ionization detector (GC-FID) analysis.

Results

Grass relative to concentrate feeding increased the content of C18:3 n-3 (54.5 vs. 25.1 mg (100 g)^–1; p < 0.001), C20:5 n-3 (19.8 vs. 12.0 mg (100 g)^–1; p < 0.001), C22:5 n-3 (20.4 vs. 15.6 mg (100 g)^–1; p < 0.001) and C22:6 n-3 (7.5 vs. 5.5 mg (100 g)^–1; p < 0.001). Total FAs were increased in LD, compared to QF muscle (p < 0.001). Correspondingly, LC n-3 polyunsaturated fatty acid (PUFA) was higher in QF muscle, compared to LD (p < 0.001).

Conclusions

Consumption of grass-finished lamb, naturally enriched in n-3 PUFA, may contribute to improved dietary n-3 PUFA intake, which has been associated with reduced risk of noncommunicable diseases such as cardiovascular disease.