| This dissertation includes studies on the effect of dietary CLA on the growth, fat accumulation and fatty acid status of chicken, and chicken meat quality as influenced by irradiation. Results showed that dietary CLA did not have significant effects on the growth rate and feed efficiency in chicken. And high levels of dietary CLA slightly reduced the whole body fat content. High ratio of dietary CLA can incorporate into chicken meat and egg yolk. Dietary CLA reduced the concentration of monounsaturated fatty acids. The concentration of polyunsaturated fatty acids, including arachidonic acid, linoleic acid and linolenic acid, also reduced as the dietary CLA level increased. However, when the dietary level of linolenic acid in diet was high, dietary CLA stimulated the synthesis of DHA and EPA, which might directly relate to the biological effects of CLA. High level of dietary CLA influenced the quality of meat, which was slightly harder and drier compared to the control meat. Dietary CLA significantly improved the oxidative stability of chicken meat. The reason for the improved oxidative and color stability of meat patties during storage should be due to the reduced unsaturated fatty acid content in chicken muscles, which improved lipid and color stability and reduced volatile production in both irradiated and nonirradiated meat during storage. Irradiation greatly increased the volatile production and induced a metal-like off-odor in chicken rolls, and dietary CLA had synergistic effect on this metal-like off-odor. Irradiation also increased the redness of chicken rolls. Consumers had a preference for the color of irradiated chicken rolls, while their reactions to the flavor of irradiated chicken rolls were quite negative. |
