Process optimization of microwave drying for rice based on response surface methodology

Area of Science:

• Agricultural Engineering
• Food Science and Technology
• Biochemistry

Background:

• Microwave drying offers efficiency but requires optimization to maintain rice quality.
• Nutritional and biochemical components like vitamins and minerals are sensitive to drying parameters.
• Understanding the impact of drying conditions on rice quality is crucial for food processing.

Purpose of the Study:

• To optimize the microwave drying process for paddy rice.
• To investigate the effects of hot air temperature, microwave power, and grain layer thickness on rice quality.
• To establish a multi-index optimization model for improved rice drying.

Main Methods:

• Utilized response surface methodology with a Box-Behnken design.
• Analyzed the influence of three key factors on four nutritional and biochemical indicators.
• Developed and validated a multi-index optimization model.

Main Results:

• All response indicator models were statistically significant.
• Optimal parameters: 52.47°C hot air, 20 kW microwave power, 2.78 cm grain layer.
• Predicted values: 3724 mg/kg K, 113.7 mg/kg Ca, 0.290 mg/100g Vit B₁, 21.5 mg/100g FFA.
• Validation showed <3% error, confirming model reliability and improved rice quality.

Conclusions:

• The optimized microwave drying process significantly improves rice quality.
• The established model provides a reliable theoretical basis for practical rice drying.
• Visual process reference charts aid in adjusting parameters for industrial production.