Influence of hempseed cake and soybean meal on lipid fractions in bovine M. longissimus dorsi

Sixteen Swedish Red steers were fed a hempseed cake (HC) or soybean meal (SM) protein supplement. Lipid extract from fresh and cooked M. longissimus dorsi were analysed. Diet comparison showed that HC had increased monounsaturated fatty acid proportion, primarily 18:1 cis-9 in the meat (P<0.05). Additionally, HC steers had higher proportions of 18:1 trans-11 and 18:2 c-9, t-11 (P<0.05). Furthermore, HC steers had decreased n-6/n-3 fatty acid ratio compared to SM steers (P<0.05). Cooking increased polyunsaturated fatty acid (PUFA) and n-6 level, particularly 18:2n-6 and 20:4n-6 (P<0.05). Cooking decreased the proportion of 17:0 and 18:0 (P<0.05). In polar lipid, HC steers had lower saturated fatty acid (P<0.05) and higher PUFA levels (P<0.05). Warner-Bratzler shear force and lipid content were unaffected by dietary treatment. Cooking decreased the triacylglycerol level of both groups (P<0.01). We conclude that HC is a viable alternate supplement for beef diets which improves the meat FA profile.