Search

This paper reports relationships between fatty acids (FAs) and intramuscular fat (IMF)% in M. longissimus lumborum samples from 108 pasture-fed ewe lambs. Samples ranged in IMF from 1 to 6%. Relationships between %FA with total IMF% were mainly linear with percentages of saturated and monounsaturated FAs (MUFA), including trans -FAs, increasing and polyunsaturated FAs decreasing as IMF% increased. Normalized FA content data at 5.5% relative to 1.5% IMF, showed the highest relative increase for C14:0 as rates of endogenous synthesis increase with higher IMF deposition. This can be related to enhanced C12:0 elongation and lower rates of C14:0 desaturation, supported by a preferential desaturation of C18:1 trans -11 and C18:0 compared with C14:0 and C16:0 as IMF increased. The greatest normalized increase after C14:0 was anteisoC17:0 followed by other branched chain FAs and then trans -MUFA and C18:2 cis -9, trans -11. Finally, C22:6 and C22:5 showed higher relative increase than C20:5 indicating greater rates of elongation and desaturation past C20:5 at higher levels of fatness. • Changes in fatty acids (FA) with increasing lamb intramuscular fat were reported. • Results confirm the increased saturation at higher levels of fatness. • C14:0 showed the highest relative increase followed by anteiso-C17:0 and other BCFA. • trans -Monounsaturated FA and C18:2c9,t11 showed the next greatest relative increase. • C22:6n-3 and C22:5n-3 showed higher relative increase than C20:5n-3 with increased fatness. [ABSTRACT FROM AUTHOR]

Palatability of meat is known to be affected by intramuscular fat (IMF), but the effect in relatively low-fat New Zealand lamb is unknown. This study evaluated the eating quality of 108 loins (M. longissimus lumborum) from a single flock of ewe-lambs. Loins ranged from 1.09–5.68% IMF and were stratified into 6 groups: 1.65, 2.12, 2.65, 3.20, 3.58 and 4.40%. Consumers' (n = 165) overall liking of lamb increased significantly at around 3% IMF, achieving maximum scores at 4% IMF. One consumer cluster (n = 111) showed a linear increase in overall liking with increasing IMF%, regarded as 'IMF lovers: the more the better', while a second cluster (n = 54) preferred 2.5–3.5% IMF, described as 'IMF optimizers: just the right amount'. IMF% was modestly correlated (~ + 0.25) with all sensory attributes except juiciness. Liking scores were modestly correlated with monounsaturated (~ + 0.25) and polyunsaturated (~ − 0.20) fatty acids. Results suggest aiming for IMF% levels in New Zealand lamb beyond 3% to maximize eating quality for premium markets in particular. • Consumer liking increased with increasing intramuscular fat (IMF%) peaking at 4%. • Two consumer clusters were identified with different preferences for IMF% in lamb. • Intramuscular fat was correlated with all sensory attributes except juiciness. • Liking was correlated with monounsaturated (+) and polyunsaturated (−) fatty acids. [ABSTRACT FROM AUTHOR]

Relationships between overall liking scores for cooked lamb from Chinese (n = 158) and New Zealand (n = 156) consumers, and metabolite and lipid profiles were evaluated. Consumers assessed meat from 6 to 8-month-old lambs of composite genetics fed chicory (CHIC) or grass (GRASS), and from 12 month-old Merino lambs fed a mixed pasture (PMER). On average, Chinese consumers rated the overall liking of all types of lamb similarly, while New Zealand consumers preferred meat from CHIC over PMER. However, three clusters with similar preferences were obtained for both Chinese and New Zealand consumers based on their overall liking scores. In Cluster-1 with a preference for GRASS, overall liking for Chinese and NZ consumers was positively associated with umami compounds, ortho- and pyrophosphates (related to water holding capacity of meat), triglycerides (TG) with<50 carbons (C50) and phospholipids with polyunsaturated fatty acids (PUFA); but negatively associated with amino acids and TG with > C50 with saturated (SFA) and monounsaturated (MUFA) fatty acids. In Cluster-2 with a preference for CHIC, overall liking for both types of consumers was positively associated with TG with > C50 with PUFA, and phospholipids with PUFA, but negatively associated with umami compounds, ortho- and pyrophosphates and L-anserine. In Cluster-3 with a preference for PMER, overall liking for Chinese and NZ consumers was positively associated with amino acids, ortho- and pyrophosphates, L-anserine, umami compounds, TG with > C50 with SFA and MUFA and phospholipids that contain C16:0, C16:1, C18:0 and C18:1; but negatively associated with phospholipids with PUFA and TG with < C50 that contain PUFA. Overall, the liking of lamb meat between Chinese and New Zealand consumers differed, but similar clusters were generated based on their overall liking scores. The clusters were characterized by different associations of the consumer overall liking scores with cooked meat metabolome and lipidome profiles., (Copyright © 2022 Elsevier Ltd. All rights reserved.)