Study On The Formation Of Quality Traits And Microbial Roles Of Yunnan Dry Cured Ham

Yunnan dry-cured ham is the major animal product industry in Yunnan province, with a long production history of over 300 years, it is reputed as one of the three most famous types of hams in China, and also one of the most famous dry cured hams in the world. Yunnan dry-cured ham characterized and famous for its fire-like red muscle, bright and clean fat, intense and delightful flavor, delicious and unique taste, and typical shape like Chinese musical instrument-pipa. Studies on the formation of traits and microbial roles of Yunnan dry cured ham is important for improving and developing Yunnan ham industry.l.Studies on the formation of Yunnan dry cured ham quality traitsExperimental Yunnan dry cured ham were processed by control processing technology with 36 hind legs weighed 13kg from crossbred pigs of local farm. M. Biceps Femoris (writing as BF in the follows) and M. semimembranosus (writting as SM in the follows) samples from 4 hams randomly taken at the green ham stage, salting stage(salting 14 days and 28 days), drying stage(drying 20 days and 40 days), and fermentation stage (30 days, 60 days, 90 days, 120 days) were used to analyze the changes of the following indexes, â‘ The changes of sensory index such as color, flavor, taste and texture,â‘¡The changes of physico-chemical indexes such as pH value, water activity(Aw) value, instrumental color patameters(Lightness-L, Redness-a, Yellowness-b), shear force value and the content of moisture, NaCl, protein and fat in muscle, â‘¢ The changes of hygienic indexes such as Total Volatile Basic Nitrogen(TVB-N), NaNO₂ in muscle and Peroxidation Value(POV), Acid Value(AV) in fat, â‘£The changes of flavor composition such as free fatty acids and volatile flavor compounds. The results showed that,(1)The sensory indexes such as color, flavor, taste and texture were improved with the development of ham fermentation (P<0.05).(2)The physico-chemical indexes such as moisture, water activity in SM and BF descended with ham processing, whereas the content of NaCl, protein and fat in muscle were increased. Optimum moisture, water activity in SM and BF is important to control ham surface crust and improve the ham quality.(3)The hygienic indexes such as TVB-N, NaNO₂ in muscle and acid value in fat were increased with ham processing, the TVB-N and AV changed slowly in salting and drying stages, and increased rapidly in fermentation period, whereas the POV descended during ham fermentation. Residual content of NaNO₂ in ham was met with Xuanwei ham standard (<4mg/kg). The changing trend of pH...