• 食品工程 •

### 超声强化真空干燥全蛋液的干燥特性与动力学模型

1. 河南科技大学食品与生物工程学院，河南 洛阳 471023
• 出版日期:2018-02-15 发布日期:2018-01-30
• 基金资助:
国家自然科学基金联合基金项目（U1304330）；河南省高校科技创新团队支持计划项目（17IRTSTHN016）

### Drying Characteristics and Kinetic Model of Liquid Whole Egg during Ultrasound-Reinforced Vacuum Drying

MA Yitong, ZHU Wenxue*, BAI Xiting, LUO Lei, HUANG Jing, YU Bin, LI Ning

1. College of Food and Bioengineering, Henan University of Science and Technology, Luoyang 471023, China
• Online:2018-02-15 Published:2018-01-30

Abstract: A new ultrasound-reinforced vacuum drying device was built to investigate the enhancing effect of ultrasound on the vacuum drying of viscous food. Ultrasound-reinforced vacuum drying of liquid whole egg was carried out to explore the influence of drying temperature, ultrasound energy density and irradiation time on the drying characteristics and microstructure. Furthermore, a kinetic model was established. The results showed that the internal mass transfer process could be enhanced by applying ultrasound to vacuum drying. Meanwhile, the drying rate was improved with the increase of ultrasound energy density. The drying process of liquid egg at 50 ℃ was no longer affected by ultrasound treatment at an energy density of 2.0 W/g after 2.5 h. The results of scanning electron microscopy (SEM) showed that many microtunnels were observed in the microstructure of powdered eggs, which was beneficial to enhancing the connectivity and consequently reducing water migration resistance. Nine different thin layer drying models were fitted nonlinearly with the experimental data. Comparison of correlation coefficient (R2), root mean square error (RMSE) and reduced chisquare (χ2) and verification experiments showed that R2 of the Page model was greater than 0.99, RMSE and χ2 were less than 0.01. Then, the Page model was the most suitable to describe the relationship between liquid egg moisture and drying time. The effective moisture diffusivity (Deff) was calculated according to Fick’s second law to range from 1.645 6 × 10-9 to 6.549 7 × 10-9 m2/s, which was increased with the increase of ultrasonic energy density. The linear relationship between the natural logarithm of effective moisture diffusivity and the reciprocal temperature was described by the Arrhenius empirical formula. The activation energy (Ea) was 16.151 2 kJ/mol. These results can provide a valuable basis for optimizing and controlling ultrasound-reinforced vacuum drying of liquid whole egg.