Research On Technology And Application Of Medium And Short Wave Infrared Radiation Drying For Shiitake Mushrooms

Shiitake mushroom was selected as raw material to investigate the mathematical model of the drying kinetics and the product quality by med-and short-wave infrared radiation drying According to the the response surface central composite design method, obtained the optimum technology of med-and short-wave infrared radiation drying, med-and short-wave infrared radiation-explosion puffing drying processing for producing dehydration shiitake mushroom. Based on above study, effects of different drying methods on the quality characteristics and the oxidation resistance of shiitake mushroom and rehydration on the effect of antioxidant activity and nutrient loss are discussed to obtain the drying method of high quality dried shiitake mushrooms. The conclusions can be summarized as follows:1?During med-and short-wave infrared radiation drying characteristics and change quality, drying temperature showed significant effects on drying kinetics and quality. The drying time decreased with the increase of drying temperature, but the drying rate and Deff increased. Among five fitting models, Page model was found to well describe med-and short-wave infrared radiation drying process. Shortwave infrared drying temperature, distance, power and slice thickness of dried mushrooms significantly affect the quality, but drying temperature is more significant, as the temperature rises, the lightness L first and then decreased, the color b value increased, rehydration ratio, total sugar and amino acids decreased.2?In the study of shiitake mushroom single and combined drying technology, the optimum parameters of med-and short-wave infrared radiation drying, med-and short-wave infrared radiation-explosion puffing drying processing for producing dehydrated shiitake mushroom are obtained by the single factor experiment and the response surface methodology. The optimal conditions for the production of dehydrated shiitake mushroom by med-and short-wave infrared radiation drying are radiation temperature of 55?, sliced thickness of 4.5 mm, infrared distance and powers of 120 mm and 1350W, respectively. The optimal conditions for the production of dehydrated shiitake mushroom by med-and short-wave infrared radiation-explosion puffing drying are infrared temperature of 60?, infrared power of 1350W, pre-drying moisture content of 35%, puffing temperature of 90?, vacuum temperature of 56? and vacuum time of 0.88 h.3?The quality characteristics of shiitake mushroom made by different drying methods (hot air drying (HAD) and middle and short infrared drying (IRD) are measured and analyzed. Results show that different drying methods and drying temperature on mushrooms physical indicators, nutrients and antioxidant activity were significantly affected. For physical properties, the product moisture content, color, rehydration ratio, rehydration rate the best, product quality decreases with increasing temperature. For nutritional characteristics, the mushrooms amino acid and total sugar content was no significant difference, and the higher total phenolic content by hot air drying, the nutritional quality reduced with increasing temperature; after rehydration, total phenols, amino acids and total are different degrees of sugar loss, and loss decreases with increasing temperature. For the oxidation resistance, the decreases with increasing temperature, shortwave infrared dried mushrooms have the highest antioxidant activity, but antioxidant activity loss is also up after rehydration. Generally speaking, shortwave infrared drying mushrooms had better quality.