EFFECTS OF VITAMIN E SUPPLEMENTATION ON PORK QUALITY CHARACTERISTICS OF HAMPSHIRE CROSSES AND BERKSHIRE CROSSES
HASTY, JENNIFER. EFFECTS OF VITAMIN E SUPPLEMENTATION ON PORK QUALITY CHARACTERISTICS OF HAMPSHIRE CROSSES AND BERKSHIRE CROSSES. (Under the direction of Eric van Heugten). An experiment was conducted to investigate whether pork quality characteristics could be improved by feeding supra-nutritional levels of vitamin E (as a-tocopheryl acetate) to Berkshire x PIC and Hampshire x PIC finishing pigs. Diets contained 0, 75, 150, 300 or 600 mg a-tocopheryl acetate/kg and were fed ad libitum for six weeks. Pigs were biopsied on 0, 21 and 42 d to evaluate potential pork quality. After the six-week feeding period, pigs were humanely slaughtered at a commercial facility and the right loin was taken from previously biopsied pigs for pork quality measurements. Chops were packaged and placed in refrigerated illuminated conditions and displayed for 0, 2, 4, 6 and 8 d. Loin sections were vacuum packaged, refrigerated and stored for 25, 35, 45 and 55 d. Supplemental vitamin E had no effect on improving average daily gain and tended to increase average daily feed intake. Average daily gain and gain:feed were greater for the Hampshire crosses and average daily feed intake was greater for the Berkshire crosses over the six-week feeding period. Supplemental vitamin E had no effect on carcass characteristics but there were differences between the two genotypes with Berkshire crosses having greater back fat and a lower percent yield, loin eye area, and lean percent. Supplemental vitamin E had no effect on biopsy fluid loss or pH. Hampshire crosses had greater fluid loss measured on day 42 than Berkshire crosses. There was no effect of supplemental vitamin E on initial (taken 45 min after slaughter) or ultimate (taken 24 hrs after slaughter) pH or temperature of the carcasses. There were no differences between genotype for initial pH and initial or ultimate temperature; however, ultimate pH was greater for Berkshire crosses. Serum and tissue vitamin E levels both increased with increasing levels of vitamin E in the diet and tissue vitamin E levels were greater for Hampshire crosses. Drip loss taken 24 hrs after slaughter was not affected by supplemental vitamin E and was lower in Berkshire crosses. However, there was a tendency for increasing level of vitamin E to decrease drip loss for the display chops of Hampshire crosses. Drip loss for the vacuum packaged loin sections was not affected by supplemental vitamin E and was lower in Berkshire crosses. Minolta L* values, taken 24 hours after slaughter, were not influenced by vitamin E. There was a trend for increasing levels of vitamin E to linearly increase a* and b* values. Hampshire crosses had greater a* values than Berkshire crosses, indicating redder meat. Supplemental vitamin E had no effect on any of the Minolta color values for the display chops or chops from the vacuum packaged loin sections. Berkshire crosses had lower L* and b* values and Hampshire crosses had greater a* values for both the display chops and chops from the vacuum packaged loin sections. TBARS values measured for samples collected 24 hrs after slaughter were not affected by supplementation of vitamin E but were greater for Hampshire crosses. TBARS values for Hampshire crosses were consistently greater over the display period. For day 4, 6, and 8, TBARS values decreased with increasing levels of vitamin E in the diet. No differences were seen in 0 or 2 d samples. TBARS values for Hampshire crosses decreased linearly with increasing levels of vitamin E in the diet but no effects were seen for Berkshire crosses. TBARS for chops from vacuum packaged loin sections were not affected by supplemental vitamin E and did not differ between genotype.
Advisor:Eric van Heugten; Todd See; Duane Larick
School Location:USA - North Carolina
Source Type:Master's Thesis
Date of Publication:06/11/2001