Influence Of Heat Treatment On Quality Of Chicken Broth

Chicken broth can not only increase appetite, but also provide a lot of nutrimental matters and enhance immunity. As the increased number of rejected elderly layers and a lot of time spent in boiling chicken broth, how to combine with two of them, one solution is to develop chicken broth as a result of further processing products of rejected layers. However, there is also very little research in the field. Therefore, it is very meaningful to deeply research and develop the chicken broth.In the experiment, purely Gushi hens were processed to chicken broth by different heat treatments .The experiment studied on the influence of heat treatment on nutritional ingredients, flavor components and the apparent characters of chicken broth. According to this experiment, we expected to provide theoretical reliance and technical support for industrial production of chicken broth. The results were as follows:1. At the same time, as the temperature increased, the permeable amount of protein contents increases continually, an obvious increase in the amount of soaking protein can be seen at 100℃.Between 85℃and 95℃, with the prolongation of heating time, protein contents of chicken broth increased, but the difference was not significant. At 100℃and 115℃, the longer the cooking time ranging from one to three hours is, the higher protein content is. When continue heating, a slight decline in its content. The maximum protein content was 9.788g/100mL at115℃for 180min. Different temperature, with the prolongation of heating time, calcium and phosphorus in chicken broth content was gradually rising trend. When heated at a certain time in 115℃, calcium and phosphorus content in chicken broth was significantly higher than other treatment groups.At115℃for 200min,the contents of calcium and phosphorus of chicken broth were 0.58mg/100mL,21.84mg/100mL.With the heating time ranging from 60min to 200 min, regardless of what the temperature heating, the collagen protein content of chicken broth increased continually, Similarly, at different temperatures, the collagen protein content increased significantly with the prolongation of cooking time. At 115℃for 200min, the content of collagen protein was 1845 mg/100g.2. The total content of free amino acids in chicken broth under different heat treatment was 5.3mg/100mL ~ 33.9 mg/100mL, the total content of free amino acid was 33.9 mg/100mL at100℃for 60 min; The essential amino acids index ( EAAI) was 0.602~0.944. It was apparent that the content of the different amino acids was stable and the constitutional rate of the essential amino acids in general accorded with the FAO/WHO Standard. Lys, Glu, Ala, Thr, Ser, Gly were dominant in concentration among the free amino acid, these FAA might make an important contribution to the formation of chicken broth flavor.3. In chicken broth, 49 compounds were identified , in which the number of hydrocarbons was highest,accounting for 57.14 percent ;The number of aldehydes compounds was second,accounting for 18.37 percent,Carbonyls play a key role during forming the characteristic aroma in the chicken broth. From a different temperature and time of comparison, the number of flavor ingredients identified were maximum at 115℃for 200 min; the maximum content of 2,4-decadienal as the characteristic aroma in chicken broth was reached at 115℃for 180min.4. Experimental Gushi hens were processed to chicken broth according to typically traditional processing technology. The results showed that the content of crude protein is high(0.61%); In dry sample, the content of four delicious amino acid was 5.83%.In addition ,the content of unsaturated fatty acids is rich(74.223%), denoting a high degree of unsaturation in fatty acids.