Study And Prepartion Of Thermal Reaction Duck Flavor

Our country is the great power of duck breed aquatics ,but the work of duck production and study is far from enough. Because of the limited processing time, traditional meat production producted by modern technics now are lack of flavor,so the flavor should be reinforced and meliorated.The objective of this paper was to prepare duck flavors true to nature using duck meat as raw material through ultrasonic pretreatment ,biologic enzyme hydrolysis and thermal reaction, offering stated gist of new production exploiture. The detailed results are as follows,1. The influence of heating and ultrasonic pretreatment on the duck preteolysis were studied by assaying the degree of hydrolysis of duck proteolysis . The results indicated that both heating and ultrasonic pretreatment can heighten the degree of hydrolysis of duck proteolysis. Comparatively, the degree of hydrolysis increases more obvious when it is treated by ultrasonic. The results also indicated that the optimal parameters of ultrasonic pretreatment were as follows: the proportion of duck meat and water was 1:3, intermediate frequency(49.8kH),the overall treatment time was twenty minutes and was spaced by five minutes.2. According to the protein hydrolyzing ability(expressed as Degree of Hydrolysis),five different kinds of proteinase (Protamex, Neutrase, Papain, Trypsin, Meat enzyme) fitted together to Flavourzyme were studied. The results showed that the mixture of Meat enzyme and Flavourzyme was the most effective combination. By monofactonal experiments, the optimum proportion of Meat enzyme and Flavourzyme and the optimum additive quantity were gained, it was 2:1and 0.3%.The design and optimum hydrolysis conditions of enzyme combination were investigated with response surface methodology (RSM) based on monofactorial experiments. The optimum hydrolysis parameters(when DH reached 35%) were figured out as follows: reaction time 35.26min, temperature 50.61℃,initial pH 7.33, DH reached 35%.Considering the practical operational conditions , the optimal technologic parameters were confirmed: reaction time 35.5min, temperature 50.6℃,initial pH 7.33.Thrice repeat experiments were conducted under this condition and the degree of hydrolysis could reach 34.89%.3. Thermal reactions to prepare duck flavors were studied. Use sensory evaluations on the reaction products as the guide line, the basic reaction materials and their additive quantity were determined by monofactorial experiments as follows: adding 50g hydrolyze liquor, 4g glucose,0.333gL- cysteine hydrochloric salt,0.167gL- glutamic acid, 0.5g thiamin. Temperature , initial pH and reacting time were the most important factors affecting the quality of the products. The optimum parameters of thermal reaction were gained by response surface methodology as follows: reaction temperature 112.99℃,reaction time 68.46min,initial pH6.99, sensory evaluation reached 3.9623.Considering the practical operational conditions , the optimal technologic parameters were confirmed: reaction temperature 113℃,reaction time 69min,initial pH6.99.4. The application experiments were done to salted duck with the duck flavor obtained under the optimum conditions. The optimum additive conditions of the duck flavor were confirmed based on the descriptive sensory evaluations:adding 10% duck flavor near the end of cooking.