Study on effect of boiling conditions on quality of chicken bone stock

The influences of bone sizes, solid-liquid ratio and different extraction methods including their temperature and time on the total nitrogen, amino acid nitrogen and collagen contents, as well as sensory evaluation of chicken bone stock were investigated.The results showed that: the smaller the bone sizes or the solid- liquid ratio was, the more the dissolution of the nutrients in chicken bone were, but when they were too small, the flavor became worse.The best quality were obtained at the bone size of 1cm and solid- liquid ratio of 1∶3, which total nitrogen dissolution rate of 25.99% of, amino nitrogen dissolution rate of 59.12%, collagen dissolution rate of 78.59%, sensory score 20.33 points. The quality and sensory evaluation changed significantly by different cooking methods including their temperature and time ( p < 0.05) . Compared with atmospheric pressure, the physicochemical indexes were higher obviously at higher pressure, which implicated that the extraction was carried out more thoroughly. When cooked at 115℃ for 60min, the aforementioned indexes of chicken bone stock were much higher, which the total nitrogen content of 2.8mg /mL, amino nitrogen content of 63.9mg /100mL, collagen content of 25.07mg /mL, and the chicken stock had characteristic flavor, sensory score of 23.46 points.