EFFECTS OF DIETARY RAPE SEED OIL, COPPER(II) SULFATE AND VITAMIN-E ONDRIP LOSS, COLOR AND LIPID OXIDATION OF CHILLED PORK CHOPS PACKED IN ATMOSPHERIC AIR OR IN A HIGH OXYGEN ATMOSPHERE

The effect of addition of rapeseed oil (canola), CuSO4 and vitamin E ( all-rac-alpha-tocopheryl acetate) to pig diets on pork meat quality (l ipid oxidation, colour and drip loss) was studied. Pigs were reared on ten different diets, either a control diet (no supplementation of rap eseed oil, CuSO4 or vitamin E) or 6% rapeseed oil diets supplemented w ith CuSO4 (0, 35 or 175 mg/kg) and vitamin E (0, 100 or 200 mg all-rac -alpha-tocopheryl acetate/kg). The natural content of vitamin E origin ating from feed ingredients amounted to 9-23 mg vitamin E (alpha-tocop herol) per kg feed. Muscle vitamin E levels reflected the dietary inta ke and pigs fed the control diet had significantly lower levels than p igs fed rapeseed oil diets. The quality of fresh pork chops packed in air or in 80% O-2:20% CO2 was followed during chill storage for 8 and 13 days, respectively. Colour, as measured by tristimulus colorimetry of pork chops packed in 80% oxygen atmosphere, was significantly impro ved with respect to redness when compared to chops packed in air, rega rdless of dietary treatment. The low vitamin E content in pigs fed the control feed significantly decreased a values and the oxidative stabi lity of pork chops during chill storage compared to the other feeding groups. Packing of chops in a high-oxygen atmosphere increased lipid o xidation, especially in chops with low levels of vitamin E. Supplement ation of rapeseed oil diets with 100 or 200 mg vitamin E significantly decreased lipid oxidation of chill stored chops. Supplementation with CuSO4 did not influence meat quality attributes (drip loss, colour st ability and lipid oxidation) for any of the storage conditions. (C) 19 98 Elsevier Science Ltd. All rights reserved