The combination of air drying and microwave-vacuum puffing is being used in Germany and Poland for fruits and vegetables. As the food industry does not disclose all its production processes, we cannot expect this list to be complete. Hauri (1989) has provided values for the necessary investment and the specific energy requirements of five different drying methods (Table 1). Based on the same throughput, the investment needed for microwave-vacuum drying is rather high, while the energy figures are more favorable than for air drying.