Dried fruits are popular due to their extended shelf life and nutritional benefits. However, the small size of the fruit and the presence of the pit make the process challenging. Removing the pit leads to an increase in food waste, while drying the whole fruit using traditional methods can be inefficient and time- onsuming. To address this, the present study investigates the drying behavior of an entire plum using icrowave-vacuum drying technique through numerical modeling. A three-dimensional porous, three-phase model of plum is developed, including the fruit flesh and the pit. The model simultaneously solves the Helmholtz equation for the electric field, Darcy’s equation, and heat and mass transfer under transient conditions, capturing the drying process. A sensitivity analysis is also performed on fruit size, chamber pressure, evaporation constant, and input power to evaluate each parameter’s impact on the process. The findings revealed that the process is directly correlated with the electric field distribution, leading to a consistent pattern of induced heat distribution throughout the process. Additionally, it is found that the average temperature is mostly affected by chamber pressure, with an ultimate range of 36- 60◦ C, and the moisture ratio is influenced by fruit size, with an ultimate range of 0.13- 0.22.

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