Use of Red Wine Polyphenols as a Natural Preservative in Health-Promoting Omega-3 Fatty Acids-Enriched Lamb Patties.

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.

Effect of dietary supplementation of vitamin E on characteristics of lamb meat packed under modified atmosphere.

The effect of dietary vitamin E supplementation on modified-atmosphere packed lamb meat during storage was studied. Thirty-six weaned male Manchego breed lambs were fed diets supplemented with three different vitamin E concentrations (0, 250, 500 and 1000mg/kg feed) for an average of 37 days, in the 13-26kg live weight growth range. Slices of m. longissimus dorsi were packaged under modified atmosphere (70% O(2) and 30% CO(2)), stored at 2±1°C in darkness for 14 and 28 days. Meat quality parameters after both storage periods were assessed. Dietary vitamin E supplementation significantly increased α-tocopherol concentration in muscle. Initially, lipid oxidation (TBARS), meat colour and bacterial load were similar in all groups. Lipid and colour oxidation of meat increased significantly (P<0.001) throughout storage. The increase was greater in non-supplemented lambs than in supplemented ones. The bacterial counts after 28 days of storage reached the limit for microbiological shelf life (7log(10)cfu/cm(2)). Dietary vitamin E supplementation increased the shelf life of meat packaged under modified atmosphere to 14 days. TBARS, pigment oxidation and bacterial load were inside the acceptable limit. The meat maintained its quality for 28 days of storage only when lambs were fed with the 1000mg/kg dietary supplement, though the bacterial load was at the limit of acceptability.

Effect of dietary supplementation with red wine extract or vitamin E, in combination with linseed and fish oil, on lamb 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 C20:5n-3 were greater (p<0.05) and n-6/n-3 ratio (p<0.01) was lower, relative to controls.

Effect of dietary supplementation with either red wine extract or vitamin E on the volatile profile of lamb meat fed with omega-3 sources.

The effect of dietary supplementation with either vitamin E (300 ppm) or a red wine extract rich in polyphenols (900 ppm) in an omega-3 enriched concentrate on the volatile fraction of lamb meat was assessed. The effect of refrigerated storage (0 and 6 days) 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 6 days of storage which could be due to further interactions with protein-related compounds.

Changes in the fatty acid composition of M. longissimus dorsi of lamb during storage in a high-oxygen modified atmosphere at different levels of dietary vitamin E supplementation.

The effect of vitamin E supplementation on fatty acid composition during storage of lamb meat packed in a high-oxygen modified atmosphere was studied. Lambs were fed with diets supplemented with four levels of vitamin E (0, 250, 500, and 1000 mg acetate-alpha-tocopherol/kg feed). Slices of M. longissimus dorsi were packed in a high-oxygen modified atmosphere (70% O2:30% CO2) and stored at 2 +/- 1 degrees C in the dark for 14, 21, and 28 days. The nonsupplemented group (E0) showed an increase in saturated fatty acids (SFA) and monounsaturated fatty acids and a reduction in polyunsaturated fatty acids (PUFA) in total fatty acids. The proportion of SFA and PUFA was unchanged in the supplemented groups (E250, E500, and E1000). The supplementation with 250 mg acetate-alpha-tocopherol/kg feed prevented the oxidation of PUFA in the total lipids and in the polar lipids fraction, while 500 mg acetate-alpha-tocopherol/kg feed was necessary to prevent the oxidation of PUFA in free fatty acids. Supplementing vitamin E not only inhibited lipid oxidation but also maintained nutritional value [essential fatty acids, linoleic acid (C18:2n-6) and linolenic acid (C18:3n-3), and beneficial fatty acids, eicosapentaenoic acid (C20:5n-3) and docosahexaenoic acid (C22:6n-3)] throughout the storage period.