Study On Mushroom Of Heat‐pump Drying Technology

Lentinus edodes belongs to the Basidiomycota,Basidiomycetes, Agaricales,Light velvet fungi,mushrooms belong.Lentinus edodes taste delicious,nutrient rich,pleasant aroma,not only has a high nutritional value,but also has health care function is unique,it is a nutrition health care food low in fat and high in protein. Heat-pump drying technology was used in the process of Lentinus edodes drying in this study.The heat-pump drying characteristics and the rule of quality changes for Lentinus edodes were studied,and kinetic models of heat-pump drying were established correspondingly to search optimal drying technology for Lentinus edodes.Meanwhile,control technology of formaldehyde content of dehydrated Lentinus edodes,and influence of different drying technologies on quality characteristics was investigated.The purpose of all above was to provide an important recommendation for practical industrialization of Lentinus edodes by heat-pump drying.1.The heat-pump equipment was used to research drying characteristics of Lentinus edodes.Effects of temperature, humidity, wind speed, loadage, initial moisture content and body size on the drying rate were also investigated, from which the rule of water changes during the process of heat-pump drying was obtained.And the drying process was divided into two stages that were accelerated phase and decelerated phase.During the drying,the higher temperature and wind speed, the less humidity and loadage,the less initial moisture content and body size was,the more frequent the dehydrating rate and shorter the required time was.2. According to the drying characteristics of heat-pump drying,the drying kinetics model for Lentinus edodes was established.The drying kinetics model agreed with Page equation ? ?N-?rtMR exp,wher 654321--???01.06.0696.2-X319.0-035.0004.0620.1 XXXXXr,654321???X012.0-X833.0-X633.6-X248.0-X015.0X005.0916.0N, P<0.001,R2>0.99.It was proved that predicted datas were nearly accordant to experimental datas,and this model could be used to describe the change of moisture of Lentinus edodes during the process of heat-pump drying.3. The influences on the content of fat, content of protein,content of formaldehyde, content of total sugar and content of vitamin during heat-pump drying were studied.(1):The content of fat declined with the increase of temperature,humidity and loadages,the content of fat increased with the increase of wind speed.(2): The content of protein declined with the increase of temperature,humidity and loadages,the content of protein increased with the increase of wind speed.(3): The content of formaldehyde declined with the increase of temperature and wind speed,the content of formaldehyde increased with the increase of humidity and loadages.(4): The content of total sugar declined with the increase of temperature and humidity,the content of tatal sugar increased with the increase of wind speed.The content of total sugar climbed up first and decline with the increase of loadages.(5): The content of vitaminC declined with the increase of temperature,humidity and loadages,the content of vitamin increased with the increase of wind speed.4. In 40% humidity conditions,the optimal technology was obtained by twice regression orthogonal experiment,with the parameters of temperature,wind speed and loadages,with sensory quality,formaldehyde content and drying time as index.The optimal technology was showed as follows: the temperature of 54℃,the wind speed is 3m/s,loadage is 1176 g.5. Three edible fresh-keeping agents have the function of inhibite the content of formaldehyde.In accordance with the inhibiton rate, the order is: L-glutamate cysteine>glutamic acid>ascorbic acid.Using the response surface method to choose the optimal combination: L-glutamate cysteine was 0.11mg/mL, the concentration of glutamic acid is 0.11mg/mL, and the concentration of ascorbic acid was 0.12mg/mL.6. Study on the effects of hot-air drying, microwave vacuum drying and heat-pump drying rate of three kinds of drying technology, rehydration ratio, shrinkage ratio and sensory quality and energy consumption of Lentinus edodes.The results showed that:(1) Hot-air dried Lentinus edodes shrinkage rate is the highest, the poor performance of complex water, heatpump drying shrinkage ratio lowest, best rehydration ratio.(2)Heat-pump drying sensory score was the highest, followed by microwave vaccum drying, hot-air drying sensory scores lowest.(3)Energy consumption calculations of three drying technology,the heat-pump drying energy consumption minimum,followed by microwave vavuum drying,hot-air drying energy dissipation.Study on three drying technology of Lentimus edodes quality influence,the results show that: heat-pump drying technology of Lentimus edodes products comprehensive quality optimal.