METHOD FOR ACCURATELY DETERMINING MOISTURE CONVERSION POINT FOR HOT AIR-MICROWAVE DRYING PROCESS OF EDIBLE FUNGUS BASED ON LOW-FIELD NUCLEAR MAGNETIC RESONANCE

The disclosure relates to a method for accurately determining a moisture conversion point for a hot air-microwave drying (HA-MWD) process of an edible fungus based on low-field nuclear magnetic resonance (LF-NMR)， and belongs to the field of fine and deep processing of agricultural products. The disclosure uses LF-NMR to determine changes in the transverse relaxation curve of moisture distribution of a fresh edible fungus during a hot air drying (HAD) process， and accurately determines the moisture conversion point according to changes in the height and width of a main peak that occupies the largest proportion of area. In this way， the disclosure effectively improves the combined drying efficiency of the edible fungus， and reduces the loss of active ingredients of the dried product. When the height of the main peak occupying the largest proportion of area in the transverse relaxation curve of moisture distribution abruptly decreases and the width thereof abruptly increases， a moisture site of the material is determined as the moisture conversion point. The disclosure makes full use of the characteristics of hot air and microwave drying methods that are suitable for removing moisture in different states.