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To elucidate the puffing characteristics of the berry slice under continuous microwave conditions, heat and mass transfer and deformation of slices were investigated based on the models of coupled multi‐physics fields involving electromagnetic heating, heat and mass transfer and solid mechanics. The results indicated that transmission mode of microwaves in a microwave cavity determined the electric field distribution inside slices with interior focusing phenomenon described by higher temperature and lower moisture content at the central region of slices than that of edge. The berry slice volume showed a "invisible‐rapid‐maintained" deformation under the synergistic effects of temperature, moisture and internal pressure with sample movement. This study may provide guidance for the elucidation of microwave puffing process of the moving slice and the underlying applications such as technology optimization and quality control of slices like berry. Novelty impact statement: This work investigates the puffing characteristics of the moving berry slices under a continuous microwave dryer, and elucidates the heat and mass transfer and deformation process of berry slices by means of experiment and simulation. The distribution of alternating electric field profiles with high and low levels determine the absorption of microwave energy, heat and mass transfer in berry slices to induce the volume deformation and uneven distribution. The volume of berry slices laid on moving conveyor belt under continuous microwave puffing undergoes three deformation trends as invisible change followed by rapid expansion till desired shape. [ABSTRACT FROM AUTHOR]

To enrich the berry product variety and improve the edible quality of blue honeysuckle berry (BHB), on the basis of determining the mixture recipe of the BHB pulp, fructose, and yoghurt (BHBY), the combined technology of microwave vacuum concentration (MVC) and freeze‐drying (FD) was proposed to produce novel BHBY snack. The results showed that the highest retention rate of anthocyanin content was 94.83% under a vacuum pressure of −0.05 MPa and a temperature of 50°C. The optimal FD parameters for the concentrated BHBY were determined as critical moisture content of 1.89 g/g (dry basis), material thickness of 13 mm, and desorption temperature of 36.9°C with a snack of hardness of 1,943.9 g, brittleness of 604 peaks, L* value of 36.7, and a* value of 20.7. The final BHBY snack presents acceptable taste with crispy texture and desired color. The developed processing technology is feasible for BHB snack. Practical applications: This work developed a novel BHB snack by the application of MVC followed by FD technology and optimized the processing technology to achieve the desired product with high drying efficiency, preferable texture taste, and considerable retention of anthocyanin content. The recipe of BHBY and the processing technology proposed was beneficial for improving the edible quality of BHB. Further, it may provide guidance for the development of novel snack and deep processing of berry fruits like BHB. [ABSTRACT FROM AUTHOR]