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This study analyzed a new drying method using airborne ultrasound combined with microwave vacuum to study its effect on the quality characteristics and microstructure of dehydrated L. edodes. Ultrasonic treatment resulted in many micropores in the product, forming the sponge effect caused by ultrasonic waves, which can promote the rapid evaporation of water in the product. Samples of Lentinula edodes individuals were dried using four methods: hot air drying (HAD), microwave vacuum drying (MVD), microwave vacuum drying after ultrasonic pretreatment (US+MVD) and airborne ultrasonic treatment combined with microwave vacuum drying (USMVD). The results showed that USMVD can reduced the loss of total sugar, total phenol, and total antioxidants in L. edodes, and increased the relative content of ergosterol, sulfur compounds, and free amino acids (p < 0.05). Scanning electron microscope observation revealed that USMVD resulted in a uniform reticular porous structure, which could better maintain desirable levels of nutrients. Therefore, USMVD can produce high quality products. Practical Application Airborne ultrasonic waves combined with MVD provides an innovative drying method for mushrooms, which has not been studied at present. The mixed drying method has great potential in maintaining product quality. It provides a theoretical basis for studying drying technology in the future.

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This study presents the effects of ultrasound (US) on the drying kinetics of lotus seeds in a hybrid dryer equipped with constant microwave power in combination with airborne US at vacuum degree (USMVD) and atmospheric pressure (USMD) from 120 to 440 W of five US power levels. Water‐borne US pretreatment before microwave drying (US + MD) or microwave vacuum drying (US + MVD) was simultaneously performed to compare their effectiveness in drying lotus seeds under the same US power. USMD and USMVD techniques reduced the drying time up to 26.19% and 14.29% while reducing energy consumption by up to 10.42% and 23.02% when compared with MVD and MD (without US), respectively, and with relatively high ultrasonic power density. The US + MD and US + MVD drying also reduced the processing time and energy consumption compared to MD and MVD process, respectively, but was less effective than USMVD and USMD. In addition, with higher US power applied, drying occurred more rapidly with less energy consumption. The newly proposed model showed the best fit to the drying curve based on model with the highest regression coefficient, lowest root mean square error, sum square error, and chi‐square. Furthermore, the enhanced effectiveness by USMVD and USMD could be attributed to the respective “heating” and “synergistic” effects generated by microwave and US. Therefore, US in combination with MVD or MD could be used jointly owing to the enhanced process effectiveness. Practical applications Drying process is one of the most complex and energy‐consuming processes. The drying kinetics model was applied in drying equipment engineering. The drying kinetic model studies the law of moisture changes during the drying process and provides a theoretical basis for the adjustment of the lotus seed drying equipment parameters. In order to improve the quality of drying products and optimize the drying process, it is necessary to use mathematical model to simulate the drying process under different drying conditions. This study provides data support for equipment selection, energy saving, and consumption reduction and industrial design of lotus seeds drying process.

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