Effect of sex, age, and pre-slaughter conditioning on pH, temperature, tenderness and colour of indigenous South African goats

Sex, age and pre-slaughter conditioning effects on pH, temperature, colour and tenderness properties of M. semimembranosus (SM) of indigenous South African goats were investigated. Sex and age had no significant effect on pH. However, female goat carcasses cooled significantly slower than those of intact males. The carcasses of 2-teeth goats had the slowest and those of the 4–6-teeth goats the fastest cooling rates. The carcasses of pre-slaughter conditioned goats had higher temperatures and lower pH values than the non-conditioned goats at both three and 24 hours post-mortem. Of the meat quality traits, colour was affected mainly by sex and age. Intact males had lower 24-hour a* and chroma values than the females and castrates. Chevon from 2-teeth goats had higher 24-hour and 96-hour a* and 24-hour chroma values than that from the milk-, 4–6and 8-teeth groups. The milk-teeth goats had a lighter colour (96-hour L* value) than the 8-teeth goats. Pre-slaughter conditioning resulted in longer sarcomeres, lower Warner-Bratzler shear force values and generally a better meat colour. Tenderness and colour properties of chevon were found to be highly dependent on post-mortem pH and temperature as well as the ultimate pH attained by the carcasses. Carcasses that chilled slowly and had a fast decline in pH yielded better quality chevon. _______________________________________________________________________________________