Optimization of Almond Kernels Drying under Infrared-vacuum Condition with Microwave Pretreatment using Response Surface Method and Genetic Algorithm

Authors
Department of Biosystems Engineering, Faculty of Agriculture, Bu-Ali Sina University, Postal Code: 6517833131, Hamedan, Islamic Republic of Iran.
Abstract
The aim of this study was optimization of almond kernels drying with infrared-vacuum dryer and microwave pretreatment using Response Surface Methodology (RSM) and Genetic Algorithm (GA). The almond kernels were dried as thin layer with air temperatures of 30, 45 and 75°C vacuum pressures of 20, 40 and 60 kPa and microwave powers of 270, 450, and 630W. Design expert software was used to generate the experimental designs, statistical analysis, and regression models. The results showed that the optimum point for drying of almond kernels under infrared-vacuum dryer and microwave pretreatment with RSM method and considering the minimum value of shrinkage, energy consumption, and total color change as well as the maximum value of effective moisture diffusivity can be achieved at air temperature of 45°C, vacuum pressure of 34.04 kPa, and microwave power of 270W with 68% desirability and optimum point with GA method can be obtained at air temperature of 45°C, vacuum pressure of 34.05 kPa and microwave power of 270W.

Keywords


1. Abdallah, A., Ahumada, M. H. and Gradziel, T. M. 1998. Oil Content and Fatty Acid Composition of Almond Kernels from Different Genotypes and California Production Regions. J. Am. Soc. Hort. Sci., 123:1029-1033.
2. Aghbashlo, M., Kianmehr, M. H. and Samimi-Akhijahani, H. 2008. Influence of Drying Conditions on the Effective Moisture Diffusivity, Energy of Activation and Energy Consumption during the Thin-Layer Drying of Beriberi Fruit (Berberidaceae). Energy Convers. Manag., 49: 2865–2871.
3. Artnaseaw, A., Theerakulpisut, S. and Benjapiyaporn, C. 2010. Development of a Vacuum Heat Pump Dryer for Drying Chili. Biosys. Eng., 105: 130–138.
4. Atkinson, A. C. and Doney, A. N. 2002. Optimum Experimental Designs. Oxford University Press, Oxford.
5. Calin-Sanchez, A., Szumny, A., Figiel, A., Jałoszyn´ski, K., Adamski, M. and Carbonell-Barrachina, A. A. 2011. Effects of Vacuum Level and Microwave Power on Rosemary Volatile Composition during Vacuum–Microwave Drying. J. Food Eng., 103: 219–227.
6. Deshpande, R. P., Chinnan, M. S. and McWatters, K. H. 2008. Optimization of a Chocolate-Flavored, Peanut–Soy Beverage Using Response Surface Methodology (RSM) as Applied to Consumer Acceptability Data. LWT, 41: 1485–1492.
7. Doymaz, I. 2007. The Kinetics of Forced Convective Air-Drying of Pumpkin Slices. J. Food Eng., 79: 243–248.
8. Doymaz, I. 2011. Thin-layer Drying Characteristics of Sweet Potato Slices and Mathematical Modeling. Heat Mass Transfer, 47:277–285.
9. FAO. 2012. Statistics. www.FAO.org.
10. Figiel, A. 2010. Drying Kinetics and Quality of Beetroots Dehydrated by Combination of Convective and Vacuum-microwave Methods. J. Food Eng., 98: 461–470.
11. Frias, A., Clemente, G. and Mulet, A. 2010. Potato Shrinkage during Hot Air Drying. Food Sci. Technol. Int., 16: 337-341.
12. Guadagni, D. G., Soderstrom, E. L. and Storey, L. 1978. Effect of Controlled Atmosphere on Flavor Stability of Almonds. J. Food Sci., 43:1077-1080.
13. Hatamipour, M. S. and Mowla, D. 2002. Shrinkage of Carrots during Drying in an Inert Medium Fluidized Bed. J. Food Eng., 55: 247-252.
14. Izadifar, M. and Zolghadri Jahromi, M. 2007. Application of Genetic Algorithm for Optimization of Vegetable Oil Hydrogenation Process. J. Food Eng., 78: 1–8.
15. Lee, J. H. and Kim, H. J. 2009. Vacuum Drying Kinetics of Asian White Radish (Raphanus sativus L.) Slices. LWT - Food Sci. Technol., 42: 180–186.
16. Mongpraneet, S., Abe, T. and Tsurusaki, T. 2002. Accelerated Drying of Welsh Onion by Far Infrared Radiation under Vacuum Conditions. J. Food Eng., 55: 147-156.
17. Montgomery, D. C., and Douglas C. 2005. Design and Analysis of Experiments: Response Surface Method and Designs. John Wiley and Sons, Inc., New Jersey.
18. Motevali, A., Minaei, S., Khoshtaghaza, M. H. and Amirnejat, H. 2011. Comparison of Energy Consumption and Specific Energy Requirements of Different Methods for Drying Mushroom Slices. J. Energy, 36: 6433-6441.
19. Nazghelichi, T., Aghbashlo, M. and Kianmehr, M. H. 2011. Optimization of an Artificial Neural Network Topology Using Coupled Response Surface Methodology and Genetic Algorithm for Fluidized Bed Drying. Comput. Elect. Agric., 75: 84–91.
20. Prabhanjan, D. G., Ramaswamy, H. S. and Raghavan, G. S. V. 1995. Microwave Assisted Convective Air Drying of Thin Layer Carrots. J. Food Eng., 25: 283– 293.
21. Sharma, G. P. and Prasad, S. 2001. Drying of Garlic (Allium sativum) Cloves by Microwave–hot Air Combination. J. Food Eng., 50: 99–105.
22. Swasdisevi, T., Devahastin, S., Ngamchum, R. and Soponronnarit, S. 2007. Optimization of a Drying Process Using Infrared-vacuum Drying of Cavendish Banana Slices. Songklanakarin J. Sci. Technol., 29(3): 809-816.
23. Tunde-Akintunde, T. Y. and Ogunlakin, G. O. 2011. Influence of Drying Conditions on the Effective Moisture Diffusivity and Energy Requirements during the Drying of Pretreated and Untreated Pumpkin. Energy Convers. Manage., 52: 1107–1113.
24. Valverde, M., Madrid, R. and Garcia, A. L. 2006. Effect of the Irrigation Regime, Type of Fertilization, and Culture Year on the Physical Properties of Almond (cv. Guara). J. Food Eng., 76: 584–593.
25. Wu, L., Orikasa, T., Ogawa, Y. and Tagawa, A. 2007. Vacuum Drying Characteristics of Eggplants. J Food Eng., 83:422–429.
26. Yam, K. L. and Papadakis, S. E. 2004. A Simple Digital Imaging Method for Measuring and Analyzing Color of Food Surfaces. J. Food Eng., 61: 137–142.
27. Yongsawatdigul, J. and Gunasekaran, S. 1996. Microwave–vacuum Drying of Cranberries: Part II. Quality Evaluation. J. Food Proces. Preserv., 20: 145–156.