Optimization Of Production Process Of Egg Dry

The study was granted by the subtopic of the National Science and Technology Pillar Program during the12th Five-year Plan Period (No.2012BAD28B08-5) and focused on the optimizing production process of egg dry. Egg pulp and soy isolate protein powder were used as raw material on the research. The physical index of egg dry was measured by texture analyzer. The first cycle hardness, gumminess, coherence, viscosity, chewiness and elasticity were used as evaluation index. The best stewing and baking process parameters were optimized by one-factor-at-a-time (OFAT) experiment and response surface methodology (RSM). Then obtained egg dry was seasoned through sensory evaluation method and orthogonal experiment. A king of egg dry with good nutrition and good physical properties were produced. The results were as follows:(1) The optimized key technology of stewing process of egg dry was studied. Egg pulp and soy isolate protein powder were compounded according to a certain proportion and then treated by stewing. The first cycle hardness, gumminess, coherence, viscosity, chewiness and elasticity were used as evaluation index. The effect of ratio of soy isolate protein powder and water, churning time and stewing time on physical index of egg dry were studied using OFAT experiment. The suitable values of factors were obtained at:ratio of soy isolate protein powder of20%, ratio of water of20%, churning time of50s, and stewing time of15min. Based on the results of OFAT, RSM was used to construct a quadric equation about stewing process, Y=0.88680-0.058583X1+0.00225X2+0.011583X3-0.18442X4-0.022750X1X2-0.025250X,X3+0.053250X1X4+0.028250X2X3+0.046250X2X4-0.031750X3X4-0.13053X12-0.028525X22-0.090025X32-0.25553X,2, in the equation:Xj was ratio of soy isolate protein powder (%); X2was ratio of water (%); X3was churning time (s); X4was stewing time (min). Partial derivatives was calculated and the optimal stewing process parameters of best physical property of egg dry were obtained at:ratio of soy isolate protein powder of19%, ratio of water of22.35%, churning time of51s, and stewing time of16.14min, under this conditions, the aggregative indicator ofphysical property of egg dry was0.991226.(2) The optimized key technology of baking process of egg dry was studied. Egg dry obtained through optimized stewing process were treated by baking. The aggregative indicator of physical property of egg dry was used as evaluation index. The effect of surface temperature, bottom temperature and baking time on physical property of egg, the suitable values of factors were:surface temperature of160℃, bottom temperature of210℃and baking time of8min. Based on the results, RSM was used to construct a quadric equation about baking process, Y=0.867820.016395X1-0.021981X2-0.020664X3-0.005765X1X2-0.046131X1X3-0.016636X2X3-0.15485X12-0.006697X22-0.040916X32, in the equation:X1was surface temperature (℃); X2was bottom temperature (℃); X3was baking time (min). Partial derivatives was calculated and the optimal banking process parameters of best physical property ofegg dry were obtained at:surface temperature of158.1℃, bottom temperature of201.9℃and baking time of7.66min, under this conditions, the aggregative indicator ofphysical property of egg dry was1.(3) The optimized seasoning process based on the sensory evaluation method of egg dry was studied. With the egg dry treated under the optimal conditions as raw material, the additive amount of salt, sugar, soy sauce, chili powder and aniseed powder were used as factors for orthogonal experiment L16(45). Original flavor egg dry was produced by optimized the additive amount of the five flavor through sensory evaluation method. The optimized processing parameters were:the additive amount of salt, sugar, soy sauce, chili powder and aniseed powder were0.3%,0.1%,8.0%,0.8%,0.1%, respectively. In this condition, the egg dry showed the features of crispy skin outside, soft inside and had a good tenacity, especially al dente. In addition, it had a fragrant flavor, with moderate salty and no other peculiar smell.(4) The nutritional ingredient contents of egg dry were measured according to GB:protein of80.5±4.5%, fat of4.4±1.6%, water of4.7±1.9%, ash content of3.2±0.7%. The contents of arsenic, mercury, lead concentrations in egg dry are all lower than the national standard. The microbial indicators also meet the demands of national standard.