Abstract:Bananas are the most widely planted tropical fruit in the world by far. They are rich in nutrients and have the effects of promoting gastrointestinal peristalsis, clearing heat and moistening lungs and protecting cardiovascular and cerebrovascular. Bananas are soft and hard to store, which lead to huge waste. Microwave vacuum drying technology is a new drying technology combining vacuum drying and microwave drying. In order to study the microwave vacuum drying characteristics and quality of banana chips, the effects of different drying factors on the drying rate and quality of banana chips were discussed, at different drying temperatures (45℃, 50℃, 55℃ and 60℃), microwave power density (28W/g, 53W/g and 82W/g), vacuum degree (75kPa, 80kPa, 85kPa and 90kPa) and thickness of banana slices (4mm, 6mm, 8mm and 10mm), microwave vacuum drying experiments were carried out, and Weibull model was used to fit the drying characteristic curve of banana slices under microwave vacuum drying. The results showed that with the increase of drying temperature, power density and material thickness, the drying time was shortened. Weibull model can simulate the microwave vacuum drying process of banana slices accurately. The scale parameters were decreased with the increase of drying temperature, power density and thickness, while the drying conditions had little effect on the shape parameters. Meanwhile, drying temperature, microwave power density, vacuum degree and banana slice thickness all had significant influence on color. ΔE* value was decreased with the increase of temperature and vacuum degree, while increased with the rise of microwave power density and material thickness. Microwave power density and material thickness had significant influence on the rehydration ratio. When the microwave power density was chosen as 28W/g and the thickness of banana slices was 4~8mm, the dried banana slices had higher rehydration and better rehydration performance. The best drying parameters of banana chips were 60℃of drying temperature, 28W/g of power density, 90kPa of vacuum degree, and 6mm of material thickness. Under such conditions, banana chips had the best crispness, can form a certain pore structure, and the pore distribution was uniform and consistent, and the quality was the best. This research explored the drying kinetics and quality of banana chips under microwave vacuum drying, which provided theoretical basis for the application of microwave vacuum drying technology of banana slices.