04160naa a2200265 a 450000100080000000500110000800800410001902200140006002400390007410000190011324501810013226000090031350005930032252027690091565000200368465300170370465300090372165300160373065300120374670000190375870000140377770000200379170000180381177300650382910029612019-02-04       2004    bl uuuu     u00u1 u    #d  a0309-17407 a10.1016/S0309-1740(03)00160-82DOI1 aREALINI, C. E.  aEffect of pasture vs. concentrate feeding with or without antioxidants on carcass characteristics, fatty acid composition, and quality of Uruguayan beef.h[electronic resource]  c2004  aArticle history: Received 17 March 2003 // Received in revised form 13 June 2003 // Accepted 13 June 2003. This research was funded by the Uruguayan National Institute of Agricultural Research (INIA), Inter-American Development Bank (IDB) and the Uruguayan Ministry of Livestock, Agriculture and Fishery (MGPA). We wish to thank the Uruguayan Hereford Breeders Association, the Uruguayan Association of Natural Intensive Beef Producers (AUPCIN), the Uruguayan Technological Laboratory (LATU), Roche Ltd., and Dr. R. Radi and Dr. H. Botti for their support and cooperation in this project.  aABSTRACT. Thirty Hereford steers were finished either on pasture (n = 10) or concentrate (n = 20) to determine dietary and antioxidant treatment effects on carcass characteristics, fatty acid composition, and quality of Uruguayan beef. Half of the steers finished on concentrate were supplemented with 1000 I.U. vitamin E head-1 day-1 for 100 days. Postmortem vitamin C was added to ground beef (0.05% v/w) displayed for 8 days at 2 °C. Carcasses from steers finished on concentrate had greater (P < 0.05) carcass weight, conformation, degree of finishing, fat depth, and ribeye area than pasture finished animals. Carcasses from pasture-fed steers showed darker (P < 0.05) longissimus color and yellower (P <0.05) fat at 24 h postmortem than concentrate-fed. Initial longissimus Warner-Bratzler shear force (WBSF) values were similar (P >0.05) between pasture- and concentrate-fed animals. However, beef from pasture-fed cattle had lower (P < 0.05) WBSF values at 7 and 14 days postmortem. Longissimus ?-tocopherol concentrations were greater (P < 0.01) for pasture- and concentrate-fed animals that were supplemented with vitamin E compared to concentrate-fed. Steaks from pasture-fed and vitamin E supplemented cattle had similar (P > 0.05) TBARS values, which were lower (P < 0.05) than steaks from concentrate-fed steers during 21 days of display. Ground beef from vitamin E supplemented steers had the lowest TBARS values; whereas samples from pasture-fed animals had the lowest lipid stability with higher TBARS levels than other treatments. Vitamin C addition to ground beef did not (P > 0.05) reduce lipid oxidation. Vitamin E supplementation of concentrate-fed cattle had no effect (P > 0.05) on color stability of ground beef or steaks. The a* (redness) and b* (yellowness) values were higher (P < 0.05) when vitamin C was added to ground beef. Longissimus fatty acid content of concentrate-fed animals was twofold greater (P < 0.01) than pasture-fed. The percentages of C14:0, C16:0, and C18:1 fatty acids were higher (P < 0.01) in the intramuscular fat of concentrate-fed steers, whereas pasture-fed cattle showed greater (P < 0.01) proportions of C18:0, C18:2, C18:3, C20:4, C20:5, and C22:5. Total conjugated linoleic acid (CLA) and CLA isomer c9t11 were higher (P < 0.01) for pasture- than concentrate-fed cattle. Vitamin E supplementation of concentrate-fed steers increased lipid stability of ground beef and steaks, but was unable to improve color stability; whereas vitamin C addition to ground beef increased color stability without altering lipid oxidation. Finishing cattle on pasture enhanced the unsaturated fatty acid profile of intramuscular fat in beef including CLA and omega-3 fatty acids.  © 2003 Elsevier Ltd. All rights reserved.  aGANADO DE CARNE  aANTIOXIDANTS  aBEEF  aCONCENTRATE  aPASTURE1 aDUCKETT, S. K.1 aBRITO, G.1 aDALLA RIZZA, M.1 aDE MATTOS, D.  tMeat Science, March 2004, volume 66, Issue 3, pages 567-577.