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Meat consumption has been related to a higher risk of heart disease due to its saturated fat content. As a consequence, there has been a growth in research on how to increase unsaturated fat content in meat. However, a high content of unsaturated fat favours the development of oxidative processes. The aim of the study was to evaluate the effectiveness of a red wine extract (RWE) rich in polyphenols (50, 100, and 200 mg gallic acid equivalents/kg meat) as a natural antioxidant in lamb meat patties enriched with omega-3 polyunsaturated fatty acids (n-3 PUFA) (100 mg n-3 PUFA/100 g meat), compared to using -tocopherol (TOC) (100 mg/kg meat). Adding RWE delayed metmyoglobin formation, lipid oxidation and loss of n-3 PUFA relative to controls, while TOC had no effect on preventing meat oxidation. Lamb odour was lower (p < 0.01) and odd odour higher (p < 0.001) in patties at the highest dose of RWE, compared to controls, but the overall liking score was not affected. The results suggest that RWE could be used as a natural antioxidant in the meat industry, even when n-3 PUFA content is high.

Spain is the biggest olive oil producer in the world what means that this area is especially affected by olive mill waste pollution. The main system used for extracting olive oil is the continuous two-phase centrifugation system, which generates olive wet cake waste. This wastage has disposal problems due to its phytotoxicity and high moisture content, so strategies for its use and revalorization are needed. One of these strategies is the extraction of bioactive compounds, as is the case of polyphenols present in the waste, which could be used as natural antioxidants in food. This study evaluated the effect of adding an olive waste extract (100, 200 or 400 mg gallic acid equivalents/kg muscle), as a possible natural polyphenol-rich antioxidant on the stability of lamb meat patties enriched with omega-3 fatty acids, and stored in high-oxygen modified atmosphere packs for up to 9 days at 4 °C. Addition of the extract delayed meat discolouration, lipid oxidation (p ≤ 0.001) and protein carbonylation (p ≤ 0.001), and increased loss of thiol groups (p ≤ 0.05) relative to controls. Fish odour (p ≤ 0.01) and flavour (p ≤ 0.05) were lower and odd odour and flavour (p ≤ 0.001) higher in patties with added the extract compared to controls, but the overall liking score was not affected. The addition of the extract resulted in acceptable lamb meat patties (in terms of oxidation) after 6 days of storage, while patties without extract did not. The results pointed out the potential for using olive waste extracts as natural antioxidants in meat products. With this strategy, the olive oil industry would encourage to follow an eco-friendlier olive oil production chain obtaining marketable products from the wastes generated. At the same time, the shelf-life (in terms of oxidation process) of the lamb patties would be increased reducing food wastes at the point-of-sale and at consumer level, which is especially important in a high perishable food such as minced meat products, and reduc

In the present study, we investigated the effect of dietary supplementation with microalgae rich in DHA (C226n3) on the fatty acid composition of different fat deposits and muscles in light lambs. Two dietary treatments were studied control (CT) and microalgae (MT), containing 2% of DHA- rich microalgae. Dietary incorporation of microalgae modified fatty acid composition in all anatomical locations studied (intramuscular, subcutaneous and kidney knob and channel fat); however, intramuscular fat was the most affected deposit. Intramuscular fat of MT lambs had higher levels of DHA (3.35%) and total n3 fatty acids (5.71%), than that of CT lambs (0.25 and 1.23% respectively). Dietary supplementation with microalgae produced a greater proportion of DHA and total n3 in M. Infraspinatus (IM) (5.12 and 8.13% respectively) compared with M. Longissimus (LM) (3.35 and 5.71% respectively) and M. Psoas major (PM) (3.62 and 6.24% respectively). Dietary supplementation with microalgae enhanced the nutritional quality of lamb muscle with more favourable PUFA/SFA and n6/n3 ratios in conjunction with increased levels of DHA and total n3 fatty acids. © 2016 Elsevier Inc.

The aim of this work was to improve the fatty acid profile of meat from light lamb, frequently reared in Spain and in other Mediterranean countries. A total of 44 light lambs fed different n-3 polyunsaturated fatty acids sources were studied control (C) (palm oil), extruded linseed (L), extruded linseed mixed with microalgae (LM) and fish oil (FO). The productive performance from 14.7 to 26.2 kg of live weights and meat quality characteristics during refrigerated storage were assessed. Lambs fed FO showed lower feed intake (p < 0.001), average daily gain (p < 0.001) and higher feed conversion ratio (p < 0.001) than lambs from the other treatments. Fish oil meat had the lowest (p < 0.01) protein proportion and the highest (p < 0.001) C205n-3, C225n-3 and C226n-3 proportions, while L or LM produced the highest (p < 0.001) C183n-3 deposition. Fish oil meat had higher (p < 0.05) L* and lower (p < 0.001) a* than meats from the other treatments. After 7 days of storage, FO meat showed the highest TBARS (p < 0.001), while C meat showed similar value to 0 days of storage. Additionally, FO underwent higher microbial growth after 7 days of storage as compared to the other treatments. Dietary supplementation with L and LM leads to C183n-3 meat enrichment and to a microbial load and colour characteristics similar to those of C, without adverse effect on lamb performance. However the use of FO improves the fatty acid profile of meat, but negatively affects lamb performance and meat quality.

Thirty lambs were assigned to the following treatments control diet (C) rich in omega-3 fatty acids; C plus 900ppm red wine extract (RWE), or C plus 300ppm vitamin E (VE). Oxidative stability and sensory properties of chops stored in MAP (70% O2/30% CO2) during 12days were evaluated. Chops from the VE group showed lower lipid oxidation (p<0.001) and protein carbonylation (p<0.05), stable omega-3 fatty acids proportions and overall liking sensory scores (p<0.05). Dietary RWE supplementation did not influence oxidative stability of chops, however levels of C205n-3 were greater (p<0.05) and n-6/n-3 ratio (p<0.01) was lower, relative to controls. © 2014 Elsevier Ltd.

The effect of dietary supplementation with either vitamin E (300ppm) or a red wine extract rich in polyphenols (900ppm) in an omega-3 enriched concentrate on the volatile fraction of lamb meat was assessed. The effect of refrigerated storage (0 and 6days) under high-oxygen atmospheres (70% O 2/30% CO 2) was also studied. Extraction and analysis of the volatile compounds was carried out by headspace solid-phase microextraction (HS-SPME) and GC-MS, respectively. Vitamin E supplementation led to lower levels of lipo-oxidation compounds, such as 2-heptanone and 1-penten-3-ol. The red wine extract was less efficient against lipid oxidation than vitamin E but more efficient than the control (no added antioxidants). The levels of numerous lipid-derived compounds were found to be lower after 6days of storage which could be due to further interactions with protein-related compounds. © 2012 Elsevier Ltd.

Fatty acid content and sensory characteristics of meat from light lambs fed three diets supplemented with different sources of n-3 fatty acids (fish oil, extruded linseed and extruded linseed plus microalgae) and a control diet during refrigerated storage have been studied. The meat from lambs fed linseed diets had the highest levels of C183 n-3, while animals fed fish oil had the highest long-chain n-3 polyunsaturated fatty acids (PUFA). Thus, 100. g of meat from lamb fed the fish oil diet provided 183. mg of long-chain n-3 PUFA, representing 40% of the daily recommended intake. The levels of n-3, n-6 and long-chain n-3 PUFA decreased during a 7-day storage period. The meat from lambs fed the fish oil diet had high scores of fish odour and flavour and rancid odour and flavour and the lowest overall liking. Rancid odour and flavour increased after storage, mainly in supplemented groups. © 2010 Elsevier Ltd.

Changes in chemical composition, with special reference to fatty acids, as affected by cooking, were studied in low-salt (0.5%)/low-fat patties (10%) with added Wakame (3%) and partial or total replacement of pork backfat with olive oil-in-water emulsion. The addition of Wakame and olive oil-in-water emulsion improved (P<0.05) the binding properties and the cooking retention values of moisture, fat, fatty acids and ash, which were close to 100%. Partial and total replacement of animal fat with olive oil-in-water emulsion reduced (P<0.05) saturated fatty acids (SFAs), while total replacement also reduced (P<0.05) polyunsaturated fatty acid (PUFAs) contents. The fatty acid concentration in cooked patties was affected by product formulation. Unlike the case of all animal fat patties, when olive oil was added the cooking process increased (P<0.05) SFAs, monounsaturated fatty acids (MUFAs) and PUFA n-3 (linolenic acid) and n-6 (linoleic acid) contents. Cooked formulated patties with seaweed and partial or total replacement of pork backfat by oil-in-water emulsion and with seaweed added were less calorie-dense and had lower SFAs levels, while samples with olive oil had higher MUFAs levels. © 2011 Elsevier Ltd.

It is well known that the eating quality of lamb is highly affected by feeding systems. The aim of this study was to ascertain acceptability of Uruguayan lamb meat from animals fed on different diets (only pasture-D1, only concentrate-D4 and two combinations of both systems-D3 and D4) by consumers from different European countries (Spain, Germany, United Kingdom and France). One hundred and twenty castrated Corriedale lambs were reared to 28.2 ± 0.8 kg live weight and then thirty lambs were allocated to each diet and reared to 40 kg live weight. Sections of loin were cooked using contact grills until the internal temperature of the muscle reached 72 °C (65 °C in France), cut and then served to consumers. A minimum of 180 consumers per country evaluated overall liking, flavour and tenderness acceptability of lamb from the 4 diets in sessions of 10 consumers using 8-point category scales. Globally consumers preferred lamb fed on concentrate or the combination of concentrate and pasture to lamb fed only on pasture. However, different segments of consumers were identified in each country based on their lamb acceptability. This information contributes to the identification of developing different commercial strategies in relation to the consumer segments found. © 2008 Elsevier Ltd. All rights reserved.

Eighty Hereford steers were used to evaluate the effect of finishing diet [A pasture, B pasture plus concentrate (0.6% live weight), C pasture plus concentrate (1.2% live weight), D concentrate] on consumer acceptability of Uruguayan beef in France (FR), United Kingdom (UK), Spain (ES) and Germany (DE). Consumers (200 per country) evaluated overall, tenderness and flavour acceptability of beef (8 point scale 1 'dislike extremely', 8 'like extremely'). FR and UK rated lower acceptability scores for beef from D compared with A, B, and C. ES showed similar results for tenderness, but flavour scores did not differ between A and D. German consumers preferred beef from B and C. Overall, low levels of supplementation on pasture produced beef with the highest consumer acceptability followed by beef from pasture-fed animals. Feeding cattle with concentrate only may not be necessary to satisfy the EU market resulting in more profitable production systems for Uruguayan producers. © 2008 Elsevier Ltd. All rights reserved.

Forty-eight Manchega breed suckling lambs were slaughtered at 10, 12 and 14 kg live weight. Carcass degree of fatness was assessed by three assessors on carcass colour photographs, using the European Union scale for light lambs (EU) subdivided into 0.25-point intervals. Left half-carcasses were jointed and dissected into lean, fat and bone. Muscle percentage, bone percentage and whole fat percentage (obtained by addition of every fat depot subcutaneous fat, intermuscular fat, inguinal fat and kidney knob and channel fat) were determined. Ten kilograms group showed a higher number of variates significantly correlated to assessors' fatness scoring than 12 and 14 kg groups; no statistically significant regression was seen in 14 kg group. Results suggest that, as live weight increases, the utility of this method to predict carcass and joints tissue composition in suckling lamb carcasses decreases. EU scale associated with weight variates can really improve prediction of carcass composition. It would be interesting to extend this study in order to determine a similar effect on the prediction of heavier groups of carcasses. © 2005 Elsevier B.V. All rights reserved.

The acceptability of beef from Uruguay (UY), based on eating quality, was compared with beef produced in different European countries (Germany, DE, Spain, ES and United Kingdom, UK). Consumer tests were conducted in DE, ES and UK (each comprising 200 consumers) using 'Hall Tests'. In each country four samples were evaluated, two from Hereford steers from UY (finished at 2 and 3 years) and two from local meat (the same meat sample aged 7 or 20 d). Consumers evaluated tenderness, flavour and overall acceptability using 8-point category scales. Hierarchical cluster analysis, highlighted the existence of different clusters of consumers. Two main clusters were identified in DE and UK. The main cluster identified in DE, was labelled as Prefer foreign-imported beef (n = 128). These consumers preferred (P < 0.05) the samples from UY_2y in terms of tenderness and overall acceptability. The other cluster was labelled as Prefer local beef in terms of flavour and overall acceptability (P < 0.05) and comprised the majority of consumers from ES (n = 176) and UK (n = 153) and the cluster 2 from DE (n = 69). UK, cluster 2 (n = 33) that did not discriminate between origin and ageing time of beef. These results indicate that consumers did not prefer the same type of meat within the same country and it is possible that there are individual preferences that could lead to the concept of market segmentation being based on taste preferences. It would appear that Uruguayan beef would be very acceptable in Germany and to a lesser extent in Britain and Spain, although further studies are required that include labelling information. © 2006.

Body composition was evaluated in 49 males and females suckling lambs of the Manchego breed slaughtered at 10, 12 and 14 kg. Lambs slaughtered at 14 kg had a greater proportion of loin-rib than those slaughtered at 10 kg. Male lambs exhibited a larger forequarter (neck, anterior rib and shoulder) while females had larger loin-rib. Slaughter weight affected the distribution of fat, and proportion of fat in loin-rib increased with slaughter weight. Males at 10 kg had more muscle in shoulder and neck than females. Significant slaughter weight × gender interaction was observed for total fat proportion in leg, loin-rib, anterior rib and flank. These proportions increased with slaughter weight in male lambs while in female lambs remained constant. The carcass composition of the suckling lamb showed significant correlations with muscle, fat and bone of the individual cuts, mainly leg and loin-rib. As expected, the proportion of muscle in the carcass was highly correlated with muscle in loin-rib, leg and shoulder. In conclusion, carcass composition may be predicted from the composition of leg and loin-rib. © 2005 Elsevier B.V. All rights reserved.

In the present study German (DE), Spanish (ES) and British (UK) consumers' acceptance of lamb from their own country compared to lamb from Uruguay (UY) was evaluated. Two-hundred consumers in each country evaluated tenderness, flavour and overall acceptability of four types of lamb, two from UY (light and heavy lambs aged 20 d) and 2 local (with two ageing times, 7 and 20 d). In each country 1.5 cm-thick slices of lamb were evaluated by previously selected consumers in controlled conditions. DE and UK consumers showed significantly (P < 0.05) different acceptability scores between samples, the lamb from heavier animals and aged 20 d being the most appreciated. On the other hand the majority of the ES consumers significantly (P < 0.05) preferred the meat from lighter lambs. Production systems, cultural aspects and consumption habits seem to affect the acceptability of the lamb to the consumers. © 2005 Elsevier Ltd. All rights resreved.

The effects of carcass weight (<5.5 kg, 5.5-6.5 kg, ≥6.5 kg) of Manchego suckling lambs, type of fat depot of the leg (subcutaneous, intermuscular and intramuscular) and muscle (m. longissimus dorsi (LD) or m. quadriceps femoris (QF)) on the fatty acid composition were studied. Carcass fatness increased with increasing carcass weight. However, few differences in fatty acid proportion were observed between the three carcass weight groups. The lightest carcasses had lower proportions of myristic (C140) and palmitoleic (C161) acid and higher proportions of stearic (C180) acid, desirable fatty acids (DFA) (C180 + total unsaturated fatty acid (TUFA)) and a greater nutritive value ((C180 + C181)/C160). The fatty acid composition of subcutaneous and intermuscular fat depots of the leg were similar, whereas the intramuscular fat depot was different from both of these, since it had a lower proportion of saturated fatty acids (SFA), a greater proportion of TUFA, higher PUFA/SFA and n - 6/n - 3 ratios, and greater DFA and nutritive values. The intramuscular fat of the LD was more saturated than QF, higher SFA, and had lower value of PUFA/SFA ratio and DFA. These results indicated that the intramuscular fat quality of the leg was better than subcutaneous and intermuscular fat depots and also that intramuscular fat displayed better attributes of quality (lower SFA, higher TUFA, and greater PUFA/SFA ratio and DFA as well) than intramuscular fat of the LD from the consumer health standpoint. Despite carcass weight affected carcass fatness, it did not seem to influence the proportions of saturated or polyunsaturated fatty acids. For this reason, carcass weight probably had little effect on the organoleptic characteristics of the meat. © 2005 Elsevier Ltd. All rights reserved.

Eighty-seven Manchego sucking lambs raised exclusively on maternal milk were slaughtered. The carcasses were weighed immediately after dressing and classified according to hot carcass weight (HCW) low HCW (<5.5 kg), medium HCW (5.5 to 6.5 kg) and high HCW (≥ 6.5 kg). The effects of this classification system on carcass and meat quality were studied. Carcass conformation improved as carcass weight increased; carcasses became more compact. Carcass fatness increased (P<0.001) as carcasses became heavier. With regard to the joints, leg (P<0.001) and shoulder (P<0.05) proportions decreased as carcass weight increased, whereas loin-rib (P<0.001) and flank (P<0.001) proportions increased. The proportion of fat in the leg clearly increased in the heavier carcasses (P<0.001), while that of bone decreased (P<0.001) and that of muscle was not affected. pH at 24 h in the m. longissimus dorsi and m. semitendinosus decreased as carcass weight increased. The only meat colour parameter affected by carcass weight was the yellowness index; lighter-weight carcasses displayed lower index (P<0.05). Cooking losses were unaffected as carcass weight increased, whereas with regard to tenderness, the shear force value tended to be higher in the low carcass weight group. No differences between carcass weight groups were found in the sensory analysis. Fatty acid composition did not show any significant effect due to carcass weight except in stearic fatty acid (C180); C180 proportion decreased (P<0.01) as carcasses became heavier. Carcass weight affected carcass quality (all carcass quality parameters studied were higher in the heavier carcasses), whereas meat quality varied little as a result the small variation between carcass weights in sucking lambs.

The fatty acid composition of commercial lambs from different production systems of Spain, Germany, United Kingdom and of two types of Uruguayan lambs (heavy and light) was studied. Concentrate fed lambs, as Spanish lambs, displayed the highest proportions of linoleic acid (C182), while Uruguayan lambs, reared under extensive grazing conditions, showed the highest proportions of linolenic acid (C183), due to the great concentration of this fatty acid in grass. German and British lambs, which were fed grass and concentrate, displayed intermediate proportions of linolenic acid (C183). Heavy Uruguayan lambs had higher intramuscular fat content (5.92%) than German (4.25%) and British (4.32%) lambs, and this content was twofold higher than light lambs (Spanish (2.41%) and light Uruguayan (3.05%)). Heavy Uruguayan, German and British lambs had a low polyunsaturated/saturated (P/S) ratio due to their high saturated fatty acid (SFA) content and proportion. Principal component analysis was performed to study the relationship between fatty acids. Spanish lambs were clearly separated from the other types and were situated close to the proportions of short chain and n - 6 fatty acids and n - 6/n - 3 ratio in the data plot for fatty acid proportions. Light Uruguayan lambs were located close to long chain fatty acids, and heavy Uruguayan and British lambs were placed near the antithrombotic potential (ATT), stearic acid (C180), SFA and conjugated linoleic acid (CLA) proportions. German lambs were located between Spanish lambs and the other types. © 2005 Elsevier Ltd. All rights reserved.

Two kinds of feed (commercial concentrate vs whole supplemented barley) were compared in unweaned lambs and lambs weaned at 40 days of age, fattened at pasture and slaughtered at 28 kg live weight, in order to observe their effects on meat quality and fatty acid composition. The weaning status influenced fatness; unweaned lambs displayed a greater carcass fatness score and more kidney knob and channel fat than weaned lambs. Compared with the unweaned animals, weaned lambs exhibited higher pH values at 0 h and 45 min in the m. longissimus thoracis (LT) and at 45 min and 24 h in the m. semitendinosus. The redness index (a*) of the m. LT of weaned lambs was higher than that of unweaned lambs, and lambs fed concentrate displayed a higher yellowness index (b*) and a higher Hue value than those given whole barley. Water-holding capacity did not vary with the treatments studied. The proportion of saturated fatty acids (SFA) in intramuscular fat was higher (P≥0.001) in unweaned lambs than in weaned ones while, on the other hand, the latter displayed a higher proportion of monounsaturated fatty acids (MUFA) and a higher n-6/n-3 ratio in the same tissue. As was the case with intramuscular fat, the subcutaneous fat of unweaned lambs exhibited higher proportions of medium-chain fatty acids (C120, C140 y C160) and lower ones of stearic (C180) and oleic (C181) fatty acids than that of weaned lambs. Higher levels of heptadecenoic acid (C171) were found in the subcutaneous fat of lambs fed whole barley than in that of lambs given concentrate. PUFA/SFA and n-6/n-3 ratios were lower in the m. LT than in the m. quadriceps femoris. © 2003 Elsevier Ltd. All rights reserved.

Eighty-six male light lambs of Manchego breed were used in this study. Principal component (PC) analysis was performed to study the relationship between carcass quality variables (n=22) and between meat quality measures (n=21). The carcass quality was assessed using objective and subjective measurements of conformation and fatness besides the joints proportion and tissues proportion of the leg. The measurements used to evaluate meat quality were pH in longissimus dorsi and semitendinosus muscles, the colour, moisture, water holding capacity, cooking losses, texture and sensorial analysis on longissimus dorsi. The five first PCs explained about 77% of the total variability for carcass measures whereas for meat quality the 74% of the total variability was explained for the eight first PCs. All the carcass measurements showed similar weight to define the first PC, whereas the muscle and bone proportion as well as musclebone ratio of the leg were useful to define the second PC. The meat quality measures that were more effective to define the first PC were the meat colour measurements, whereas the sensorial variables defined the second PC. The projection of the carcass quality data in the first two PCs allowed to distinguish clearly between heavier carcasses (higher than 6.5 kg) and lighter carcasses (lower than 5.5 kg). The carcasses with a weight higher than 6.5 kg were on the left side of the figure, where the variables of conformation and fatness lie. The group of medium carcass weight were placed between the two previous groups. The projection of the meat quality data in the first two PCs did not differ between hot carcass weights, although there was a trend, the lighter carcasses lay on the left side of the graph, which implies small differences between meat quality in this range of carcass weight. © 2004 Elsevier Ltd. All rights reserved.

Forty-nine Manchega breed suckling lambs were used. Carcass weight was less than 13 kg, and lambs were slaughtered at 10, 12 and 14 kg liveweight. Carcasses were classified by three assessors on colour photographs, by several classification methods the European Union scale for light lambs carcasses (EU), Colomer-Rocher methods for fatness (CF) and conformation (CC), and the new scale for suckling lambs (SL) developed by our research group. Carcasses were also assessed using these scales divided into 0.25 point-intervals (EU-25, CF-25, CC-25 and SL-25). A correlation analysis was made between assessors score and tissue composition in the carcass and in three joints (leg, best end of neck and loin, and shoulder). For all the methods studied 0.25 point scales were best correlated to tissue composition than 1.0 points-interval scales. When 1.0 point-interval scales were used the SL scale was best correlated to tissue composition. When 0.25 point-scales were used, the EU scale gave the best correlations. Conformation scale (CC) was useful to predict carcass composition, specially kidney knob and channel fat content. © 2003 Elsevier Ltd. All rights reserved.

Correlations and regression between fatness and carcass conformation measurements and carcass tissue composition has been studied for both sexes in suckling lambs, with slaughter weights between 9 and 15 kg. Objective fat measurements showed higher correlations than subjective fat measurements, mainly with carcass fat. Conformation measurements presented greater correlations with tissues weight than with tissues proportion (r ≤ 0.50). CCW was highly correlated with total muscle in the carcass (R2 = 0.961). Two fatness measurements (KKCF proportion and dorsal fat thickness) were included for the prediction of the muscle proportion. Furthermore, the model included other measurements, such as fore cannon bone weight and internal carcass length although they displayed very low correlation coefficients. This equation explained 64.1% of the variation of carcass muscle proportion (r.s.d. = 1.532). CCW was included in the prediction equations of tissue weights, although in the fat tissue equation it appeared in the form of the carcass compactness index (CCW/L). CCW was a good predictor of the weight of carcass tissues in suckling lambs, especially for muscle. Prediction equations for tissue composition in grams were more accurate (R2 ≥ 0.91) than those for tissue proportion. When gender was included in all models it did not improve either accuracy or precision of the prediction. © 2003 Elsevier Ltd. All rights reserved.

Forty-nine Manchego-breed lambs raised exclusively on their dams' milk until slaughter were used in this study. The effects of gender and slaughter weight (10, 12 and 14 kg) on carcass fatness, meat quality and the fatty acid composition of their fat were studied. Fatness, and in particular dorsal-fat thickness (P ≤0.01), increased with live weight. The effect of gender was even greater (P ≤0.001), as female lambs presented the highest fatness values for all parameters studied. The smallest drop in m. longissimus pH values was seen in the lowest-weight (10 kg) Iambs. These same lambs displayed the highest L* value and thus the lightest colour. Fatty acid composition, which was not influenced by live weight, was affected by gender. The subcutaneous fat of female lambs contained more linolenic acid (C183) (P ≤0.01) and a greater proportion of polyunsaturated fatty acids than that of male lambs (P ≤0.001). Likewise, the intramuscular fat of female lambs displayed a greater proportion of monounsaturated fatty acids (P ≤ 0.001) than that of male lambs. © 2003 Elsevier Ltd. All rights reserved.

This study involved 53 Talaverana-breed lambs fattened until reaching a slaughter weight of 28 kg. After weaning at 45 days of age, the lambs were divided into four study groups. The lambs of two of the groups were fattened at pasture, while those of the other two groups were kept on a drylot. One group at pasture and another on the drylot received a commercial fattening concentrate. The other two groups received whole barley with a protein supplement. Drylot lambs displayed better carcass dressing, greater carcass fatness, higher carcass conformation values and a superior refrigerated carcass weight than lambs fattened at pasture. Lambs fattened with concentrate displayed better carcass dressing, higher carcass compactness and less digestive tract development (due to a lower proportion of stomach and digestive content) than those fed barley. The fat colour of lambs fattened at pasture was lighter (greater L*) than that of the drylot lambs, and the lambs fed concentrate exhibited a higher redness index (a*) than those fed barley. The longissimus dorsi (LD) muscle was used to evaluate meat quality. The lambs fattened at pasture displayed a lower lightness value, lower cooking losses and greater pleasantness scores in the sensorial analysis than drylot lambs. The lambs fattened at pasture presented lower values of fatty acids with an odd number of carbon atoms and monounsaturated fatty acids and higher linolenic acid (C 183) levels than drylot lambs in both the intramuscular fat of the LD muscle and in subcutaneous fat. The lambs fed barley exhibited a higher proportion of fatty acids with an odd number of carbon atoms and lower C 183 values than the lambs given the concentrate.

Forty-eight sucking lambs (26 males and 22 females) of the Manchega breed were used in this work. Lambs were slaughtered at 10, 12 and 14 kg live weight. Carcass degree of fatness was assessed by three assessors from colour photographs of the carcasses, using the European Union scale for light lambs (EU), the Colomer-Rocher method (CF) and another new scale developed by our group (sucking lambs scale, SL). Carcass conformation was assessed according to the Colomer-Rocher method (CC). Fatness and conformation scales were divided to give 0.25 points in each interval. Left half-carcasses were jointed and dissected into lean, fat and bone. Muscle proportion, bone proportion and whole fat proportion (obtained by addition of every fat depot subcutaneous fat, intermuscular fat, inguinal fat and kidney knob and channel fat) were determined. Male and female carcasses showed a very different tissue composition both groups had statistically significant differences (P < 0.05) in 20 out of 25 tissue composition variates. Males showed a higher number of variates that were well correlated with assessors' scoring than females. Correlation coefficients between most of the tissue composition variates and assessors' scores were higher in males. Furthermore, the number of variates that were significantly correlated with assessors' scores was lower in females. Therefore, subjective methods for the estimation of carcass degree of fatness and of carcass conformation are poor predictors of tissue composition in female sucking lamb carcasses.

Forty-nine Manchega suckling lambs were used in this trial. Lambs were slaughtered at 10, 12 and 14 kg liveweight (cold carcass weight lower than 13 kg). The degree of fatness was assessed by three assessors on colour photographs of the carcasses, using the European Union scale for light lambs (EU), and another new scale developed in our laboratory (Suckling Lamb scale, SL). Carcass degree of fatness was reassessed using the same scales divided into 0.25 point-intervals (EUI, SLI). Carcasses were allocated into four groups by means of a tree classification algorithm (cluster analysis), according to 27 variates, namely muscle percentage, whole fat percentage, subcutaneous fat, intermuscular fat, kidney knob and channel fat percentage and muscle percentage, both in the carcass and in three joints (leg, best end neck plus loin, and shoulder). SL scale groups showed a higher number of variates well correlated to assessors' scoring than EU scale groups. Nevertheless, the EU scale showed significant between-groups differences in a higher number of variates (P<0.01). Using 0.25-points interval scales, EUI scale scoring was the best correlated to tissue composition. However, most variates were better correlated to dorsal fat thickness measurement (4 cm back from last rib and 4 cm from the carcass midline) than to assessors' scoring. All four groups in the tree classification were statistically different from one another, but assessors only were able to detect differences between whole fat percentage in group 1 and the rest. These results suggest that it is possible to improve the photographic standards of the EU method by using a 0.25 points interval scale. In abattoir conditions, the new SL method (1.0 point intervals) proved to be better. Measure of dorsal fat thickness proved to be a very good predictor of carcass tissue composition, but it is a more expensive measure. © 2002 Elsevier Science Ltd. All rights reserved.

Two production systems, pasture and sheepfold based on lambs fed concentrates ad libitum was evaluated for carcass and meat quality of lambs slaughtered at body weights of 24 and 28 kg. There was no effect of production system on growth rate of lambs. In sheepfold, commercial carcass dressing values of slaughter lambs were heavier than in those raised at pasture with more dorsal fat thickness (1.6 mm vs. 1.1 mm), kidney knob and channel fat (1.6% vs. 1.2%) and a greater percentage of leg fat (8.5% vs. 6.6%). Lambs at heavier weights had more fat. Meat quality, pH, water-holding capacity and collagen content parameters were not affected by the production systems. The color of the longissimus dorsi muscle was somewhat darker in lambs fattened at pasture, but no color differences were seen in the rectus abdominis muscle. In both subcutaneous and intramuscular fat of the two cuts studied (leg and loin), sheepfold lambs presented a lower percentage of stearic acid (C180) and a higher proportion of palmitic (C160) and linoleic (C182) acids, and thus a lower percentage of SFA and a higher one of TUFA, while a better (n - 6)/(n - 3) ratio was observed in lambs raised at pasture. Lambs at heavier weights displayed a lower percentage of PUFA and PUFA/SFA ratio in the intramuscular fat of the longissimus dorsi muscle and higher levels of oleic (C181) and palmitic (C160) fatty acids and a lower one of myristic acid (C140) in both depots. © 2002 Elsevier Science B.V. All rights reserved.

Three weaning treatments (weaning at 45 days of age, at 65 days of age, unweaned) and two slaughter weights (24 and 28 kg) were compared in lambs raised at pasture, and their effect on carcass and meat traits were studied. Unweaned lambs displayed a greater growth rate, lower concentrate consumption, greater dorsal fat thickness, more kidney knob and channel fat and greater total fat levels, measured through dissection of the hind limb. Total collagen concentration was lower in unweaned lambs and the intramuscular fat of these same animals exhibited a greater proportion of saturated fatty acids and a lower n-6/n-3 fatty acid ratio. Slaughter weight influenced scored carcass fatness, which was greater in heavier lambs, meat colour, which displayed greater lightness in lower-weight lambs, and water-holding capacity, which was lower in lambs with the lower slaughter weight. The heavier lambs displayed lower soluble collagen values, and the intramuscular fat of the longissimus dorsi muscle of these same lambs contained higher levels of monounsaturated and lower levels of polyunsaturated fatty acids.

Forty-nine male Talaverana-breed suckling lambs slaughtered at 14 kg live weight were used to study the fatty acid composition of adipose depots of lambs raised under different management systems (pasture or drylot) and diets (maternal milk with or without a concentrate supplement). Drylot lambs displayed a higher fatness score, in addition to greater dorsal fat thickness; these parameters corresponded with a greater percentage of total fat at dissection. Addition of concentrate to the diet did not modify carcass fatness. Drylot lambs presented higher proportions of oleic acid (C181) and monounsaturated fatty acids (MUFA) and lower linolenic acid (C183) values in subcutaneous and intramuscular fat (muscle longissimus thoracis). The subcutaneous fat of these lambs thus displayed a higher n-6/n-3 PUFA ratio (C182/C183) than that of pasture-raised ones. Concentrate in the diet of both pasture and drylot lambs resulted in higher linoleic fatty acid (C182) and PUFA values and a greater PUFA/SFA ratio in intramuscular fat than the corresponding values of lambs which consumed maternal milk alone. Loin displayed a higher percentage of subcutaneous and intramuscular chemical fat than leg. Compared with intramuscular leg fat (muscle quadriceps femoris), intramuscular loin fat (muscle longissimus thoracis) had lower oleic acid (C181) and MUFA values, higher PUFA values and a higher PUFA/SFA ratio, due to greater linolenic acid (C183) levels. © 2001 Elsevier Science Ltd.