Abstract: The nutrient composition and edible quality of longissimus dorsi muscle from organic hilly black pigs aged different months (7, 8, 9 and 10) were analyzed to determine the optimal slaughter age of organic hilly black pigs. Water content, intramuscular fat, pH, meat color, tenderness, drip loss and cooking yield of longissimus dorsi muscle from organic hilly black pigs of different ages exhibited a significant difference (P＜0.05) or an extremely significant difference (P＜0.01). Water content of longissimus dorsi muscle from organic hilly black pigs aged at 7 months was 74.55% and gradually declined with increasing age, although protein content did not reveal an obvious difference (P＞0.05), and the maximum level of 19.56% was observed at the age of 8 months with an average of 18.63%. Intramuscular fat content showed an increasing trend with an extremely significant difference (P＜0.01) and the maximum level of 5.24% was observed at the age of ten months. At 45 min postmortem, the average brightness L1*, redness a1* and tenderness values of longissimus dorsi muscle across four different ages were 44.26, 7.49 and 57.05 N, respectively. These results suggest that longissimus dorsi muscle from organic hilly black pigs has shiny red color, is rich in proteins and minerals, and possess uniform and moderate intramuscular fat as well as excellent meat quality, and the optimal slaughter age was 8 months.

Key words: organic hilly black pigs, longissimus dorsi muscle, meat nutritional composition, mineral, edible quality