Study On The Processing Of Lentinus Edodes Crisps Using Dried Lentinus Edodes As Raw Materials

Lentinus edodes are rich in our country, of which the most popular products, at present,are hot air dried ones, which need rehydration before consumption. As for the instant Lentinusedodes foods, rare literature has been found. The objective of this study is to produce a kindof instant Lentinus edods chips using dried Lentinus edodes as material. After the rehydration,pretreatment and floavoring of the dried materials, different drying methods, hot air drying(HAD), vacuum drying (VD), microwave vacuum drying (MVD) and intermediate-infrareddrying (IIR), were used to compare the drying characteristics and the quality of Lentinusedodes chips to find out the best drying method. The optimization process was also studied inorder to obtain Lentinus edodes chips with better quality.In order to reduce the excessive loss of nutrients during the rehydration, wipe off the badsmell and improve the color and crispness of Lentinus edodes crisps, the optimizedrehydration conditions of dried Lentinus edodes has been studied, followed with somepretreatments, including blanching and the use of food additive maltodextrin. In thisexperiment, the preferred rehydrated conditions were: soaking temperature20°C of105minwith solid-liquid ratio of1:15; and the blanching conditions were: ascorbic acid inconcentration of0.06g/100mL, citric acid of0.4g/100mL and0.03g/100mL EDTA-2Na,blanching temperature of100°C with blanching time of2min; and the concentration of foodadditive maltodextrin was10%.To get the best drying method among hot air drying, vacuum drying, microwave vacuumdrying and the intermediate-infrared drying, drying characteristics, color, texture, rehydration,the lentinan content and ultrastructure of the products were compared. The study found thatmicrowave vacuum needed least drying time as well as produced Lentinus edodes crisps ofsuperior quality. Therefore, the microwave vacuum dried Lentinus edodes crisps were chosenfor further optimization studies.To get Lentinus edodes crisps with better taste, crisp texture, and favorite leisure, test ofprepared Lentinus edodes crisps recipe was investigated, and the microwave vacuum dryingconditions were optimized, resulting in a final procedure. The ultimate recipe was as follows:the maltose8%, emulsifiers0.1%, brine22%and cream15%, with sensory score8.85; and theoptimum operating conditions of microwave vacuum drying were: initial moisture content54.00%, microwave power density9.00w/g, and vacuum degree0.090MPa. In thisconditions, the crispness was494.67g, hardness was1075.67g and sensory score was9.23.In order to study the storage characteristics, the texture changes of products at68.86%RH,52.89%RH and30.85%RH and color changes at4°C,25°C and37°C were studied. Theresults showed that lower relative humidity and lower temperature were good for the stabilityof products. To assume the shelf life of products, L*was taken for the evaluating indicator inaccelerated testing. The shelf life of the ultimate products, when stored at25°C, wassuggested to be470days.