Effect of Pulsed-Spouted Bed Microwave Freeze Drying on Quality of Apple Cuboids
- 186 Downloads
The effects of novel Pulse-Spouted Bed Microwave Freeze Drying (PSMFD) technology on the quality on natural food products have been investigated. The objective of this research was to study effects of this novel technology on dielectric properties and quality characteristics (moisture content, porosity, microstructure, texture, color, and flavor) of apple cuboids as compared with the conventional drying technologies (air drying and freeze drying). During the first 45 min of drying, the dielectric properties increased due to partial conversion of water from ice to liquid, and then gradually decreased due to the moisture removal. Microwave energy increased sample temperature from minus 20 °C to + 67 °C, which resulted in fast drying to 0.09 g/g within 270 min. Porosity increased almost linearly, reaching 0.87 at equilibrium moisture content. Hardness of apple cuboids increased to 350–450 kPa due to the glass transition in the final period of drying. Better preservation of apple color and volatile compounds demonstrated the benefits of the hybrid PSMFD technology for the production of premium quality dried fruits compared to air drying and freeze drying.
KeywordsPulse-spouted bed microwave freeze dryer Drying properties Quality Dielectric properties Apple cuboids
This work was supported by the Mitacs Globalink Research Award, Canada (ATL/Industry Canada FR14904, 2016), China Key Research Program (Contract No. 2017YFD0400901), Jiangsu Province (China) “Collaborative Innovation Center for Food Safety and Quality Control” Industry Development Program, and Jiangsu Province (China) Agricultural Innovation Project (Contract No. CX (17) 2017), which have enabled us to carry out this study. The authors acknowledge the contribution of Alissa Spinney for the assistance with the manuscript proofreading.
- Chen, Z., Zhu, C., Zhang, Y., Niu, D., & Du, J. (2010). Effects of aqueous chlorine dioxide treatment on enzymatic browning and shelf-life of fresh-cut asparagus lettuce (Lactuca sativa L.) Postharvest Biology and Technology, 58(3), 232–238. https://doi.org/10.1016/j.postharvbio.2010.06.004.CrossRefGoogle Scholar
- Jiang, H., Zhang, M., Mujumdar, A. S., & Lim, R. X. (2014). Comparison of drying characteristic and uniformity of banana cubes dried by pulse-spouted microwave vacuum drying, freeze drying and microwave freeze drying. Journal of the Science of Food and Agriculture, 94(9), 1827–1834. https://doi.org/10.1002/jsfa.6501.CrossRefGoogle Scholar
- Liu, P., Zhang, M., & Mujumdar, A. S. (2012). Comparison of three microwave-assisted drying methods on the physiochemical, nutritional and sensory qualities of re-structured purple-fleshed sweet potato granules. International Journal of Food Science & Technology, 47(1), 141–147. https://doi.org/10.1111/j.1365-2621.2011.02819.x.CrossRefGoogle Scholar
- Nadian, M. H., Rafiee, S., Aghbashlo, M., Hosseinpour, S., & Mohtasebi, S. S. (2015). Continuous real-time monitoring and neural network modeling of apple slices color changes during hot air drying. Food and Bioproducts Processing, 94, 263–274. https://doi.org/10.1016/j.fbp.2014.03.005.CrossRefGoogle Scholar
- Quantachrome Instruments. (2012). Multipycnometer manual. Quantachrome Instruments, MVP-6DC.Google Scholar
- Szczesniak, A. (1963). Objective measurements of food texture. Journal of Food Science., 28(4), 410–420. https://doi.org/10.1111/j.1365-2621.1963.tb00219.x.CrossRefGoogle Scholar
- Tokuşoğlu, Ö., & Swanson, B. G. (2014). Improving food quality with novel food processing technologies. CRC Press. https://doi.org/10.1201/b17780.
- Venkatesh, M. S., & Raghavan, G. S. V. (2004). An overview of microwave processing and dielectric properties of agri-food materials. Biosystems Engineering, 88(1), 1–18. https://doi.org/10.1016/j.biosystemseng.2004.01.007.CrossRefGoogle Scholar
- Wang, R., Zhang, M., Mujumdar, A. S., & Jiang, H. (2011). Effect of salt and sucrose content on dielectric properties and microwave freeze drying behavior of re-structured potato slices. Journal of Food Engineering, 106(4), 290–297. https://doi.org/10.1016/j.jfoodeng.2011.05.015.CrossRefGoogle Scholar
- Wang, Y., Zhang, M., Mujumdar, A. S., Mothibe, K. J., & Roknul Azam, S. M. (2012). Effect of blanching on microwave freeze drying of stem lettuce cubes in a circular conduit drying chamber. Journal of Food Engineering, 113(2), 177–185. https://doi.org/10.1016/j.jfoodeng.2012.06.007.CrossRefGoogle Scholar