Influence of preslaughter resting time of bulls on meat temperature,colour and pH value

摘要

The paper presents results of meat quality evaluation in two groups of Simmental farm fattened bulls (n = 40), age from 14 to 20 months and weight from 400 to 550 kg. Animals were selected by the method of free choice and divided into two groups. The first group consisted of bulls transported from nearby. These were animals slaughtered immediately after arrival. The second group included animals transported from distant places, resting for 36 hours prior to slaughter. Preslaughter resting time of young bulls, from 400 to 550 kg of weight, reduced significantly the occurence of dark, firm, dry (DFD) meat. The major factor of DFD meat detection is muscle pH. Temperature and colour are of less value. If we take into account the limit of pH for DFD meat being 5.8, according to Jones and Tong (1989), Pem et al. (1994) and Cepin (1988, 1991, 1995) 7 animals (35%) due to pH of m. longissimus dorsi and 3 animals (15%) due to pH of m. gracilis can be qualified as DFD meat in group resting prior to slaughter. In the immediately after arrival slaughtered group these numbers are higher. There are 16 animals (80%) due to pH of m. longissimus dorsi and 12 animals (60%) due to pH of m. gracilis being qualified as DFD meat. If we, however, take into account the limit of pH for DFD meat being 6.0 (Gariepy et al., 1990) 3 animals (15%) due to pH of m. longissimus dorsi and one animal (5%) due to pH of m. gracilis can be qualified as DFD meat in group resting prior to slaughter. In the immediately after arrival slaughtered group these numbers are higher. There are 9 animals (45%) due to pH of in. longissimus dorsi and 30% of animals due to pH of m. gracilis being qualified as DFD meat.