Palatability of beef from cattle fed extruded flaxseed before hay or mixed with hay

Citation

Prieto, N., M.E.R. Dugan, I.L. Larsen, P. Vahmani, J.L. Aalhus. 2017 Palatability of beef from cattle fed extruded flaxseed before hay or mixed with hay. Meat and Muscle Biology. DOI: 10.22175/mmb2017.04.0026.

Plain language summary

This study was undertaken to evaluate the eating quality of beef ribeye steaks and hamburgers with higher levels of potentially healthy fats. The health favourable fats (n-3, vaccenic and rumenic) were improved in beef by feeding mixed co-extruded flaxseed (flaxseed, peas and alfalfa) and alfalfa-grass hay, and further enhanced by feeding the co-extruded flaxseed before alfalfa-grass hay. Compared to the mixed diet, feeding steers the diet components sequentially resulted in tougher steaks with lower beef flavor and greater off-flavor intensity. The extent of these changes in flavour might be detected by consumers. High levels of trans monounsaturated fatty acids, mainly of vaccenic acid, were associated with a fishy off-flavor, although actual changes in flavour may relate to the combined effects of other fats as well. Diet had no effect on sensory attributes of hamburgers, but when panelists described off-flavours, they noted more ‘other’ off flavours with fishy and stale/cardboard notes being more prominent in hamburgers from sequentially fed animals. Overall, beef samples in this study with vaccenic acid levels over 6.12% of total fat, while potentially having a greater health benefit, may pose challenges in terms of eating quality. Areas worthy of further investigation to ensure acceptable eating quality might be the influence of ageing on antioxidant capacity in beef with enhanced fatty acid profiles, and the potential use of protective packaging to limit deterioration.

Abstract

This study was undertaken to evaluate the eating quality of longissimus thoracis steaks and hamburgers (80/20 gluteus medius to perirenal fat) with enhanced profiles of potentially healthy fatty acids. The profile of health favourable fatty acids (n-3, vaccenic and rumenic) was improved in beef by feeding co-extruded flaxseed (flaxseed, peas and alfalfa) and alfalfa-grass hay as a total mixed ration (TMR), and further enhanced by feeding co-extruded flaxseed before alfalfa-grass hay (Non-TMR). Compared to TMR, feeding steers the Non-TMR resulted in tougher steaks (P < 0.05) with lower beef flavor (P < 0.01) and greater off-flavor (P < 0.01) intensity to an extent that might be detectable by consumers. High levels of trans monounsaturated fatty acids, mainly of vaccenic acid, were associated with a fishy off-flavor, although actual changes in flavor may relate to correlated combined effects of conjugated fatty acids, atypical dienoic acids and α-linolenic acid. Diet had no significant effect on sensory attributes of hamburgers, but when panelists described off-flavors, they noted more ‘other’ off flavors (P < 0.05) with fishy and stale/cardboard notes being more prominant in Non-TMR hamburgers. Overall, beef samples with threshold levels of vaccenic acid over 6.12% of total fatty acids resulting from feeding flaxseed products, while of potentially greater health benefit, may pose challenges in terms of eating quality. Areas worthy of further investigation to ensure acceptable eating quality might be the influence of ageing on antioxidant capacity in beef with enhanced fatty acid profiles, and the potential use of protective packaging to limit deterioration.

Publication date

2017-08-23