ABSTRACT
The effect of rapid air chilling of carcasses in the first 3 h of chilling at -31°C (then at 2-4°C, till 24 h post-mortem) and the possibility of earlier deboning (8 h post-mortem) after rapid air chilling, compared to conventional air chilling (at 2-4°C, till 24 h post-mortem) on weight loss and technological quality (pH value, tenderness, drip loss, cooking loss and colour - L(∗)a(∗)b(∗) values) of pork M. semimembranosus was investigated. Under the rapid chilling conditions, weight loss was 0.8% at 8 h post-mortem and increased to 1.4% at 24 h post-mortem when weight loss was 2.0% under conventional chilling. Carcasses that were rapid chilled had significantly lower (P<0.001) internal temperature in the deep leg at 4 (25.7°C), 6 (13.0°C), 8 (6.2°C) and 24 h (3.8°C) post-mortem compared to conventional chill treatment (32.7, 24.2, 19.1 and 5.1°C, respectively). Rapid chilling reduced significantly (P<0.05) the rate of pH value decline at 8 h (6.02) post-mortem in M. semimembranosus compared to conventional chill treatment (5.88). Compared to conventional chilling, in M. semimembranosus deboned in different time post-mortem, rapid chilling had a positive significant effect on drip loss (P<0.05, muscles deboned 8 h post-mortem), cooking loss (P<0.001) and incidence of pale colour (L(∗) value). Rapid chilling i.e. rapid chilling and earlier deboning had neither positive nor negative significant effects (P>0.05) on other investigated technological quality parameters of M. semimembranosus (tenderness, a(∗) value and b(∗) value) compared to conventional chilling.
