Effect of betaine intake on muscle and backfat characteristics of pigs.

Abstract

This study was undertaken to investigate the effects of long term betaine intake on the chemical and physical characteristics of m. Longissimus dorsi (LD), and backfat (BKF) of Alentejano (AL) pigs. Purebred AL pigs were allocated to open-air individual pens and fed a commercial (C) diet offered at 85% estimated ad libitum consumption. The pigs were divided into two experimental groups: Group C (n=6), consuming the C diet, and Group CB (n=8), consuming the C diet supplemented with betaine (1g/kg). After 20 weeks of trial, pigs were slaughtered at ~100 kg live weight (LW). LD and BKF individual samples were obtained from the chilled left half carcasses. Chemical (moisture, protein, lipids, myoglobin, and collagen) and physical (pH, water-holding capacity, CIE L*, a* and b*, chroma, and hue angle), as well as the LD area and BKF thickness, were determined. Significant differences were found mainly on the gross chemical composition and colour of LD and BKF samples. Betaine-fed pigs showed a higher (P=0.05) amount of LD neutral lipids and a lower (P<0.05) LD moisture content. Meanwhile, BKF average thickness and its lipid concentration were not affected. The fatty acid (FA) composition of lipids from LD and BKF was also not affected by treatments. On the other hand, the colour component Cie b* (yellowness) tended to be higher on LD (P=0.06) and was higher (P<0.05) on the BKF of pigs fed betaine, suggesting a global trend to a more yellowish tone in pork colour. The results obtained suggest that betaine supplementation in AL pigs has no effects on improving the lean:fat ratio of the carcass and on the LD and BKF FA profiles. However, intramuscular fat from LD was increased by betaine, as well as the yellowness on both tissues, suggesting an effect of betaine on overall pork quality.