Effects of Feeding Palm Oil in Beef Cattle Finishing Diets on Meat Quality

Abstract The objectives of this experiment were to evaluate the value of palm oils as ingredients in cattle feed compared to no fat or tallow on beef (steak) quality measures. Steers (n = 430; 472 kg; SD = 22) were allocated to 40 pens in a generalized randomized block design consisting of 3 blocks where steers were blocked by weight. Steers were then assigned to 1 of 5 dietary treatments consisting of different sources of fat supplemented at 3.5% of the diet DM: 1) No oil; negative control containing 0% supplemental fat, 2) Tallow; positive control, 3) Crude palm oil, 4) Refined, bleached, and de-odorized palm olein oil, RBD olein and 5) Crude, high oleic, palm oil, crude HOPO. Cattle were fed for a total of 160 days, and due to a delay in obtaining the palm oils from Colombia, cattle received treatments for the last 107 days before slaughter. Forty-eight h post-harvest, 3 beef strip loins were collected from each pen, individually vacuum packaged, aged for 14 d, and frozen until analysis. Color of subcutaneous fat was measured in which lightness (L*) and redness (a*) were not different among the treatments (P 0.68). Yellowness (b*) was significantly higher for the crude palm (12.9) and crude HOPO (14.2) treatments (P ≤ 0.02). After a 72 h thawing period, loins were cut into 2.54 cm strip steaks, which were used for further analysis. Retail display color was measured over a 7 d period and there were no differences observed in any color metrics across treatments (P ≥ 0.55). Furthermore, no differences were observed in lipid oxidation between treatments (P = 0.17). Moisture and total ether extractable lipid of steaks were not different between treatments (P ≥ 0.85). Fatty acid composition of steaks, trimmed of subcutaneous fat, did not differ among treatments, except for arachidonic acid, which was greater in steaks from cattle fed RBD olein (P = 0.02). After cooking each steak to an internal temperature of 71º C, tenderness was assessed using the slice shear force and Warner-Bratzler shear force tests. While steaks from all treatments were considered “very tender”, there was a tendency for tallow and RBD olein to decrease steak tenderness. Steaks from cattle fed tallow and RBD olein had slightly greater Warner-Bratzler shear force values (2.83 and 2.79 kg, respectively) compared with those from cattle fed no supplemental fat (2.54 kg; P = 0.10). Similarly, slice shear force values were greater for tallow (19.2 kg) and RBD olein (18.8 kg) compared with no added fat (16.7 kg; P = 0.15). These data suggest that adding fractions of palm oil at 3.5% of diet DM does not negatively affect meat quality relative to tallow.