Effects of animal diet, marinade, and storage time on attributes of ribeye steaks and precooked beef pot roast

This study was designed to evaluate meat from grass-fed and grain-fed beef in conjunction with different marinade effects on sensory attributes. Steers were treated similarly with the exception of diet. Color samples were taken to evaluate differences in color of fat and lean between the two diets. Individual muscles (Longissimus dorsi, Gluteus medius, Semitendinosus, Semimembranosus, Serratus ventralis, Infraspinatus and Teres major) were portioned into similar weights. Marinade treatments were randomly assigned to samples (1) Dale'sRTM steak seasoning (D), (2) Dale'sRTM steak seasoning and red wine (DW), (3) Dale'sRTM steak seasoning, Red wine and Starch (DWS), or (4) Control (C) (no marinade). Samples were placed into polyethylene bags and injected with marinade to 12% of pristine weight, then vacuum-sealed and cooked in a hot water bath. An internal core temperature of 82°C was maintained for 4 h. Samples were chilled and stored at 2.2°C until evaluated. At 7 and 60 days samples were reheated to an internal temperature of 71°C and evaluated for Warner-Bratzler shear and sensory attributes. Flavor, tenderness, warmed-over-flavor (WOF), and overall acceptability were higher (P < 0.05) for roasts containing D when compared to C for 7 d and 60 d for all roasts with the exception of Semimembranosus at 7 d. Control roasts were less acceptable (P < 0.05) than D and DW for all roasts except Semimembranosus and Gluteus medius at 60 d for flavor, tenderness, WOF, and overall acceptability. Dales RTM resulted in higher (P < 0.05) yield values than control for all steaks at each evaluation with exception of Gluteus medius at 60 d and Infraspinatus and Teres major at 7 day. Sous vide processing resulted in products with <10 cfu/gm total plate count and <1 cfu/gm coliform counts. Broiled ribeye samples were 2.54 cm thick and were cooked to a final internal temperature of 71°C and presented for sensory evaluation. Mean panelist values revealed no differences (P > 0.05) for any sensory attribute along with no shear or yield differences (P > 0.05) between grass-fed and grain-fed beef. Hunter color values revealed that grass-fed diets produced lean that was darker (P < 0.05) and fat that was more yellow in appearance (P < 0.05) when compared to grain-fed beef.