Cao Xiaohuang, Zhang Min, Qian He, Mujumdar Arun S
State Key Laboratory of Food Science and Technology, Jiangnan University, 214122 Wuxi, Jiangsu, China.
Jiangnan University (Yangzhou) Food Biotechnology Institute, Yangzhou 225002, China.
J Sci Food Agric. 2017 Jun;97(8):2307-2315. doi: 10.1002/jsfa.8040. Epub 2016 Nov 15.
An online temperature-detection-assisted control system of microwave-assisted pulse-spouted vacuum drying was newly developed. By using this system, temperature control can be automatically and continuously adjusted based on the detection of drying temperature and preset temperature. Various strategies for constant temperature control, linear temperature control and three-step temperature control were applied to drying carrot cubes. Drying kinetics and the quality of various temperature-controlled strategies online are evaluated for the new drying technology as well as its suitability as an alternative drying method.
Drying time in 70 °C mode 1 had the shortest drying time and lowest energy consumption in all modes. A suitable colour, highest re-hydration ratio and fracture-hardness, and longest drying time occurred in 30-40-50 °C mode 3. The number of hot spots was reduced in 40-50-60 °C mode 3. Acceptable carrot snacks were obtained in 50-60-70 °C mode 3 and 70 °C mode 2. All temperature curves showed that the actual temperatures followed the preset temperatures appropriately.
With this system, a linear temperature-controlled strategy and a three-step temperature-controlled strategy can improve product quality and heating non-uniformity compared to constant temperature control, but need greater energy consumption and longer drying time. A temperature-detection-assisted control system was developed for providing various drying strategies as a suitable alternative in making a snack product. © 2016 Society of Chemical Industry.
新开发了一种微波辅助脉冲喷动真空干燥的在线温度检测辅助控制系统。通过使用该系统，可根据干燥温度检测和预设温度自动连续调节温度控制。将恒温控制、线性温度控制和三步温度控制等各种策略应用于胡萝卜块干燥。对这种新干燥技术在线恒温控制策略下的干燥动力学和产品质量及其作为替代干燥方法的适用性进行了评估。
70°C模式1的干燥时间在所有模式中最短，能耗最低。30 - 40 - 50°C模式3的胡萝卜颜色适宜，复水率和断裂硬度最高，但干燥时间最长。40 - 50 - 60°C模式3的热点数量减少。在50 - 60 - 70°C模式3和70°C模式2中获得了可接受的胡萝卜零食。所有温度曲线均表明实际温度与预设温度匹配良好。
使用该系统，与恒温控制相比，线性温度控制策略和三步温度控制策略可提高产品质量并改善加热不均匀性，但能耗更高且干燥时间更长。开发了一种温度检测辅助控制系统，以提供各种干燥策略，作为制作零食产品的合适替代方法。© 2016化学工业协会。
