No abstract

No abstract

This study was conducted to determine the effects of feeding olive cake and linseed to lambs on the volatile organic compounds (VOCs) in raw and cooked meat. Four groups of eight male Appenninica lambs each were fed: conventional cereal-based concentrates (diet C), concentrates containing 20% on a dry matter (DM) basis of rolled linseed (diet L), concentrates containing 35% DM of stoned olive cake (diet OC), or concentrates containing both rolled linseed (10% DM) and stoned olive cake (17% DM; diet OCL). The longissimus dorsi muscle of each lamb was sampled at slaughter and was subjected to VOC profiling through the use of SPME-GC-MS. In the raw meat, the concentration of 3-methylpentanoic acid was higher in treatment C as compared with treatments L, OC and OCL ( P < 0.01). Moreover the level of nonanoic acid was greater in treatments C and OC than in treatment L ( P < 0.05). With respect to alcohols, in raw meat the amount of 2-phenoxyethanol in treatment OCL was lower than in treatments C ( P < 0.01) and OC ( P < 0.05), while in cooked meat the amount of 1-pentanol was higher in treatment C than in treatment OC ( P < 0.05). Apart from these compounds, none of the lipid oxidation-derived volatiles was significantly affected by the dietary treatment. Therefore, the results suggest that the replacement of cereal concentrates with linseed and/or olive cake did not cause appreciable changes in the production of volatile organic compounds in lamb meat.

Publication informationFood Research International, 115 : 54-64 Publisher Elsevier Item record/more information http://hdl.handle.net/10197/10488 Publisher's statement þÿ T h i s i s t h e a u t h o r s v e r s i o n o f a w o r k t h a t Abstract 34 Animal production factors diet can affect the sensory quality of lamb meat. The study 35 investigated the effect of diet composition and duration of consumption on theproximate 36 analysis, volatile profile and sensory quality of lamb meat. Ninety-nine male Texel × Scottish 37 Blackface lambs were raised at pasture for 10 months before being assigned in groups of 11 38 to one of the following treatments: 100% Silage (S) for 36 (S36), 54 (S54) or 72 (S72) days; 39 50% Silage 50% -50% Concentrate (SC) for 36 (SC36), 54 (SC54) or 72 (SC72) days; 100% 40 Concentrate (C) for 36 (C36) or 54 (C54) or 72 (C72) days. A trained sensory panel found 41 Intensity of Lamb Aroma, Dry Aftertaste and Astringent Aftertaste to be higher in meat from 42 lambs on the concentrate diet. Discriminant analysis showed that the volatile profile enabled 43 discrimination of lamb based on dietary treatment but the volatile differences were 44 insufficient to impact highly on sensory quality. Muscle from animals in the S54 group had 45 higher Manure/Faecal Aroma and Woolly Aroma than the SC54 and C54 groups, possibly 46 related to higher levels of indole and skatole. Further research is required to establish if these 47 small differences would influence consumer acceptability. 48 49

The aim of this study was to assess the effect of castration and slaughter age on the volatile profile of cooked meat from Scottish Blackface (SB) and Texel × Scottish Blackface (T × SB) lambs. M. longissimus thoracis et lumborum was sampled at slaughter and subjected to volatile analysis by SPME‐GC‐MS. Rams had higher relative proportions, expressed as relative abundance (RA), in lipid oxidation products while castrates had higher RA in pyrazines and benzenoid compounds. There was no consistent age effect on the RA of volatiles, although rams in November and January had a different volatile profile to castrates. There were higher proportions of free branched‐chain fatty acids in muscle from SB compared to T × SB lambs. Overall, the results showed that production factors affected the volatile profile of cooked lamb meat which may explain differences in lamb flavor. Practical Application Lamb meat has a characteristic flavor which, according to the evidence to date, may be influenced by farm production factors like gender or slaughter age. Our results showed variations in the proportions of some flavor compounds in cooked lamb between rams and castrated lambs while an increase in slaughter age did not have a consistent effect on proportions of compounds.