Trans‐10 18:1 in ruminant meats: A review

Abstract

Trans (t) fatty acids (TFA) from partially hydrogenated vegetable oils (i.e., industrial trans) have been phased out of foods in many countries due to their promotion of cardiovascular disease. This leaves ruminant‐derived foods as the main source of TFA. Unlike industrial TFA where catalytic hydrogenation yields a broad distribution of isomers, ruminant TFA are enzymatically derived and can result in enrichment of specific isomers. Comparisons between industrial and ruminant TFA have often exonerated ruminant TFA due to their lack or at times positive effects on health. At extremes, however, ruminant‐sourced foods can have either high levels of t10‐ or t11‐18:1, and when considering enriched sources, t10‐18:1 has properties similar to industrial TFA, whereas t11‐18:1 can be converted to an isomer of conjugated linoleic acid (cis(c)9,t11‐conjugated linoleic acid), both of which have potential positive health effects. Increased t10‐18:1 in meat‐producing ruminants has not been associated with negative effects on live animal production or meat quality. As such, reducing t10‐18:1 has not been of immediate concern to ruminant meat producers, as there have been no economic consequences for its enrichment; nevertheless at high levels, it can compromise the nutritional quality of beef and lamb. In anticipation that regulations regarding TFA may focus more on t10‐18:1 in beef and lamb, the present review will cover its production, analysis, biological effects, strategies for manipulation, and regulatory policy.

Inclusion of Sainfoin in the Concentrate of Finishing Lambs: Fatty Acid Profiles of Rumen, Plasma, and Muscle

“…Toral et al 30 and Huyen et al 31 studied sainfoin in vitro and in dairy cows fed sainfoin silage and observed a low BH extent and higher C18:1 c9 ruminal percentages coming from the diet. However, because the C18:1 c9 could not be chromatographically resolved from the C18:1 t13/t14 pair, the proportion of C18:1 c9 may also be related to the eventual presence of C18:1 t13 formed from the BH of C18:3 n-3, 32 which was higher in 40SF meat.…”

“…Several of the most important effects produced by sainfoin inclusion in the diet were observed in the trans -MUFAs. The study of this group of FA is important because trans -MUFAs in the food industry have been phased out due to their potential negative effects on human health so that ruminant-derived products have become one of the main sources of consumption of these types of fats . The trans -FA present in ruminant meat and milk is produced during ruminal BH, and C18:1 t10 and C18:1 t11 are the main FAs formed during this process.…”

“…The study of this group of FA is important because trans -MUFAs in the food industry have been phased out due to their potential negative effects on human health so that ruminant-derived products have become one of the main sources of consumption of these types of fats. 32 The trans -FA present in ruminant meat and milk is produced during ruminal BH, and C18:1 t10 and C18:1 t11 are the main FAs formed during this process. High ruminal concentrations of C18:1 t11 have been associated with forage-rich diets, whereas the formation of the C18:1 t10 isomer is linked with concentrate-rich diets.…”

Enrichment of ruminant meats with health enhancing fatty acids and antioxidants: feed-based effects on nutritional value and human health aspects – invited review

“…However, limited n-3 PUFA enrichments can be achieved using this approach because of extensive biohydrogenation of PUFA in the rumen (Vahmani et al, 2015) when compared with supplementing marine-based (algae) or chemically protected n-3 PUFA sources. Moreover, PUFA supplementation, particularly LA in forage diets often results in an increased tissue deposition of BHI, particularly TVA and RA, while supplementation in high-grain diets yields t10-18:1 and t10,c12-CLA (Vahmani et al, 2020;Alves et al, 2021). Given recent studies have shown that ruminant-derived trans FAs such as t10-18:1 (Vahmani et al, 2020) have similar adverse effects to that of industrial trans FAs (Verneque et al, 2022), it would be of importance to determine if the health value of beef enriched with n-3 PUFA is still maintained when different proportions of trans FAs are present.…”