Prototype continuous microwave foam-mat dryer: design and fabrication

Area of Science:

• Food Engineering
• Drying Technology
• Agricultural Processing

Background:

• Traditional drying methods can degrade the quality of fruit products.
• Microwave-assisted drying offers potential for faster and more efficient dehydration.
• Foam-mat drying is a technique that can improve heat and mass transfer during drying.

Purpose of the Study:

• To design and fabricate a prototype continuous microwave foam mat dryer.
• To evaluate the drying performance and product quality of tomato and guava using the developed dryer.
• To optimize drying parameters for enhanced physicochemical properties.

Main Methods:

• A continuous microwave foam mat dryer was designed using preliminary study data.
• The dryer integrated a submersible pump, time switch, and a drying section combining hot air and microwaves.
• Quality evaluation involved assessing physicochemical properties at varying microwave powers and air temperatures.

Main Results:

• The dryer achieved continuous operation with efficient foam delivery and flake collection.
• Optimal drying occurred at 1000 W microwave power and 50°C inlet air temperature, yielding excellent physicochemical properties.
• Performance metrics for guava included 4.84 l/h capacity, 0.059 g H2O/g d.m moisture, and 98.34% recovery.
• Tomato drying performance showed 4.03 l/h capacity, 0.062 g H2O/g d.m moisture, and 91.29% recovery.

Conclusions:

• The developed microwave foam mat dryer is effective for continuous dehydration of tomato and guava pulps.
• The process preserves high-quality physicochemical attributes in the dried products.
• This technology presents an efficient and promising method for fruit pulp processing.