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Effects of cold rearing temperature on meat quality parameters on loin and ham muscles in pigs
This study aimed at evaluating the influence of cold (C) rearing environment versus thermoneutrality (T) during post-weaning (C: 23°C to 15°C; T: 28°C to 23°C) and growing-finishing periods (C: 12°C; T: 23°C) on pig Longissimus (LM) and ham, Adductor femoris (AF), Semimembranosus(SM), Gluteus superficialis (GS), muscle metabolism and meat quality, and determining the reversibility of these effects. Three groups of pigs were constituted according to their post-weaning and growing-finishing thermal environments: CC (n=18), CT (n=18) and TT (n=24). In LM muscle, CC pigs had higher glycolytic potential (GP, P<0.001) and lower pH 24h p.m. (pHu, P<0.001), higher drip loss (P=0.02), color saturation and intramuscular fat (IMF, P<0.001) content compared with TT. In AF and SM muscles, CC pigs exhibited also lower pHu compared with TT and CT. CT pigs exhibited higher pHu, lower GP but similar IMF and drip as TT pigs in LM. No difference in color were found between CT and TT pigs in LM and GS, but CC pigs exhibited higher redness and yellowness in both muscles. Cold environment affected appearance (higher redness) and texture (lower fibrousness) of loin and improved pork odor, but did not modify tenderness or juiciness. Short and long term effects of low temperature during rearing period could explain meat quality differences at commercial slaughter weight. Most of short-term effects of cold environment on muscle metabolism are persistent at older stages and influence pork meat quality.
Keywords:
meat quality, pig, rearing temperature