Study On Optimization Of Key Processing Technology And Safety Control Of Ready-to-eat Lentinus Edodes

Lentinus edodes is edible and medicinal fungi have a long history of cultivation, and originated in China. Lentinus edodes production in China reached4.01million tons in2010, accounting for about80percent of the world’s total and ranked second in the single species of China’s edible fungus production. However, now the most products of Lentinus edodes needed secondary processing (non-instant type), such as dried Lentinus edodes, product variety pattern, unable to meet the diverse needs of consumers. For the current customers’demand for the conveniently, safe and nutritious food, Process parameters of flavor formula, dried mushrooms rehydration, vacuum marination and the microwave drying were optimized about the ready-to-eat Lentinus edodes. Meanwile without preservatives under the premise, the processing of microwave-boiling joint sterilization was optimized with response surface methodology. At last the ready-to-eat Lentinus edodes product which had popular flavor, nutrition and convenience was developed, and HACCP system was used in ready-to-eat Lentinus edodes product. The results were as follows:(1)Through the single factor tests and the orthogonal experiments, the best productive formulation of ready-to-eat Lentinus edodes was:soy sauce10%, salt9%, capsicum7%, sugar6%. At this point the product had rich mushroom incense and delicious flavor.(2) Effects of different temperature on dried Lentinus edodes rehydration were studied. The results showed that rehydration time could be shortened to15min, and improved production efficiency when dried mushroom soaked at90℃water, at the same time, the loss of water-soluble Polysaccharide contents and soluble protein contents could be reduced, and some bitterness was removed.(3) Effect of vacuum marination and atmospheric marination on ready-to-eat Lentinus edodes were compared. The results showed that the flavor of marinade could be absorbed by Lentinus edodes marinating time could be shorten2/3than the atmospheric marination, and production efficiency was improved, and mushroom had closer texture and more chewy, moreover the loss of water-soluble nutrition was reduced, while mushroom were marinated for20min under the conditions of vacuum of0.07MPa and temperature of70℃.(4)When the moisture content was controlled at68.8%to74.8%, that was hardness at11.738N to13.888N, chewiness at8.673N to10.254N and elasticity at1.000, the ready-to-eat Lentinus edodes products had moderate moisture, close, moderate hardness, better chewiness and taste, and were suitable for texture requirement of leisure food. Losing water characteristics of microwave drying about ready-to-eat Lentinus edodes can be expressed by Page equation, that was MR=exp(-KtN), mathematical mode was:ln[-ln(MR)]=0.0015P-0.056G+0.0002G2+(0.0011P+0.0181G-0.0001G2)lnt. The mode can accurately predict the water co nt-ents change of ready-to-eat Lentinus edodes by microwave drying.(5) Effects of121℃high pressure sterilization, microwave sterilization, boiling sterilization and microwave-boiling joint sterilization on total amount of bacterial and sense quality of ready-to-eat lentinus edodes were compared, the results showed that microwave-boiling joint sterilization, which combined microwave sterilization in short time and boiling processing, not only could reach the sterilizing effect, but also could keep the original flavor better. Effects of microwave time, transmitting power of unit mass and boiling processing time on total amount of bacterial of ready-to-eat Lentinus edodes after microwave-boiling joint sterilization were studied by response surface methodology, and regression equation was established, which was as follow: Y=130.33-82X1-29.88X2-1052.13X3-0.5X1X2+33XiX3+29.75X2X3+90.96X12+15.71X22+951.71X32. The optimum parameters of microwave-boiling joint sterilization were microwave time of95s, transmitting power of unit mass of4.7w/g and boiling processing time of21min. At this point, the total bacterial amount of products could be maintained below100cfu/g, and products could be stored10days at least under the conditions of37℃.(6) HACCP system was applied in the products of soft-packing ready-to-eat Lentinus edodes, the critical control points were estimated which included raw material Checking, vacuum marination, microwave drying, vacuum packing and microwave-boiling joint sterilizing, and the critical limit and preventive measures were determined, in order to ensure product quality and safety.