羊肚菌真空冷冻干燥特性的研究

Study on Vacuum Freeze-drying Characteristics of Morchella

以羊肚菌为原料,使用真空冷冻干燥技术,通过实验研究羊肚菌的干燥特性(湿基含水率W湿、干基含水率Wt、水分比MR、有效扩散系数Deff、单位能耗N)及营养成分(蛋白质、氨基酸、脂肪、磷酸盐、硒)的保留情况,以期为羊肚菌深加工提供部分参考。实验测得4月采摘的新鲜羊肚菌立即干燥测得含水量为91. 7%,完全干燥1kg羊肚菌至恒重,每小时需要2. 217kW能量,蛋白质的保留率为91. 7%,氨基酸的保留率分别为甲硫氨酸53. 8%、异亮氨酸52. 4%、亮氨酸58. 4%、赖氨酸70. 0%、苯丙氨酸47. 2%、苏氨酸55. 7%、缬氨酸52. 9%,磷酸盐的保留率为46. 4%,硒的保留率为0. 99%。真空冷冻干燥能够有效保留羊肚菌的色、香、味、形以及食品营养成分,但真空冷冻干燥方式对于能源消耗大,与其他干燥方式联合干燥是接下来的研究方向。

This study explores morchella’s dehydration features (wet basis moisture content W, Wt, MR, Deff, effective diffusion coefficient and unit energy consumption N) and preservation of nutrients (protein, amino acid, fat, phosphate and selenium) in the process of vacuum freeze drying in order to provide reference for the deep processing of morchella. The results show that the instant moisture contents of morchella is 91.7%, and that it takes 2.213kW energy per hour to completely dry 1 kg morchella. The retention rate of protein is 91.7%, and that of amino acids is 53.8% for methionine, 52.4% for isoleucine, 58.4% for leucine, 70% for lysine, 47.2% for phenylalanine, 55.7% for threonine, and 52.9% for valine 52.9%. The phosphate retention rate is 46.4%, and that of selenium is 0.99%. Vacuum freeze drying can effectively save morchella’s nutrient and preserve its color, smell, taste and form, but is costly in terms of energy consumption. Its combination with other dehydration approaches is the direction for future research.