Nutritional quality of heat-sensitive food materials in intermittent microwave convective drying
Background: The retention of health promoting components in nutrient-rich dried food is significantly affected by the dehydration method. Theoretical and experimental investigations reported in the literature have demonstrated that intermittent microwave convective drying (IMCD) can effectively improve the drying performance. However, the impact of this advanced drying method on the quality food has not been adequately investigated.
Design: A programmable NN-SD691S Panasonic inverter microwave oven (1100 W, 2450 MHz) was employed for the experiments. The microwave power level was set at 100 W and ran for 20 seconds at different power ratios and the constant hot air conditions was set to a temperature of 60°C and 0.86 m/s air velocity.
Objective: In this study, natural bioactive compounds (ascorbic acid and total polyphenol), water activity, colour and microstructure modifications which can occur in IMCD were investigated, taking kiwifruit as a sample.
Results and Discussion: The microwave (MW) power ratio (PR) had significant impact on different quality attributes of dried samples. The results demonstrate that applying optimum level MW power and intermittency could be an appropriate strategy to significantly improve the preservation of nutrient contents, microstructure and colour of the dried sample. The IMCD at PR 1:4 was found to be the ideal drying condition with the highest ascorbic acid retention (3.944 mg/g DM), lowest colour change (ΔERGB = 43.86) and a porous microstructure. However, the total polyphenol content was better maintained (3.701 mg GAE/g DM) at higher microwave density (PR 1:3). All samples attained a desirable level of water activity which is unsusceptible for microorganism growth and reproduction.
Conclusion: Overall, IMCD significantly improved the drying performance and product quality compared to traditional convective drying.
- Mujumdar AS. Handbook of industrial drying, Boca Raton, FL: CRC/Taylor & Francis; 2007.
- Kumar C, Karim MA, Joardder MUH. Intermittent drying of food products: A critical review. J Food Enging 2014; 121: 48–57. doi: https://doi.org/10.1016/j.jfoodeng.2013.08.014.
- Botha GE, Oliveira JC, Ahrné L. Microwave assisted air drying of osmotically treated pineapple with variable power programmes. J Food Eng 2012; 108(2): 304–11. doi: https://doi.org/10.1016/j.jfoodeng.2011.08.009.
- Kumar C, Kumar C, Karim A, Saha S, Joardder UH, J Brown R, Biswas D. Multiphysics modelling of convective drying of food materials. Proceedings of the Global Engineering, Science and Technology Conference, Dhaka, Bangladesh, 2012; 28–29.
- Joardder MUH, Kumar C, Karim MA. Food structure: its formation and relationships with other properties. Crit Rev Food Sci Nutr 2017; 57(6): 1190–205. doi: 10.1080/10408398.2014.971354.
- Joardder MUH, Kumar C, Karim AA. Effect of temperature distribution on predicting quality of microwave dehydrated food. J Mech Eng Sci 2013; 5: 562–8. doi: http://dx.doi.org/10.15282/jmes.5.2013.2.0053.
- Sablani SS. Drying of fruits and vegetables: retention of nutritional/functional quality. Drying Technol 2006; 24(2): 123–35. doi: 10.1080/07373930600558904.
- Barsa CS, Normand MD, Peleg M. On models of the temperature effect on the rate of chemical reactions and biological processes in foods. Food Eng Rev 2012; 4(4): 191–202. doi: 10.1007/s12393-012-9056-x.
- Defraeye T, Nicolaï B, Mannes D, Aregawi W, Verboven P, Derome D. Probing inside fruit slices during convective drying by quantitative neutron imaging. J Food Eng 2016; 178: 198–202. doi: https://doi.org/10.1016/j.jfoodeng.2016.01.023.
- Chou SK, Chua KJ, Mujumdar AS, Hawlader MNA, Ho JC. On the intermittent drying of an agricultural product. Food Bioproducts Process 2000; 78(4): 193–203. doi: 10.1205/09603080051065296.
- Chua KJ, Mujumdar AS, Chou SK, Hawlader MNA, Ho JC. Convective drying of banana, guava and potato pieces: effect of cyclical variations of air temperature on drying kinetics and color change. Drying Technol 2000; 18(4): 907–36. doi: 10.1080/07373930008917744.
- Jumah R, Al-Kteimat E, Al-Hamad A, Telfah E. Constant and intermittent drying characteristics of olive cake. Drying Technol 2007; 25(9): 1421–6. doi: 10.1080/07373930701536668.
- Thomkapanich O, Suvarnakuta P, Devahastin S. Study of intermittent low-pressure superheated steam and vacuum drying of a heat-sensitive material. Drying Technol 2007; 25(1): 205–23. doi: 10.1080/07373930601161146.
- Chua KJ, Mujumdar AS, Chou SK. Intermittent drying of bioproducts – An overview. Bioresour Technol 2003; 90(3): 285–95. doi: 10.1016/S0960-8524(03)00133-0.
- Joardder MUH, Kumar C, Karim MA. Multiphase transfer model for intermittent microwave-convective drying of food: Considering shrinkage and pore evolution. International Journal of Multiphase Flow. 2017; 95: 101–19. doi: https://doi.org/10.1016/j.ijmultiphaseflow.2017.03.018.
- Kumar C, Joardder MUH, Farrell TW, Millar GJ, Karim MA. Mathematical model for intermittent microwave convective drying of food materials. Drying Technol 2016; 34(8): 962–73. doi: 10.1080/07373937.2015.1087408.
- Kumar C, Joardder MUH, Farrell TW, Karim MA. Multiphase porous media model for intermittent microwave convective drying (IMCD) of food. Int J Therm Sci 2016; 104: 304–14. doi: http://dx.doi.org/10.1016/j.ijthermalsci.2016.01.018.
- Barbosa de Lima AG, Delgado JMPQ, Neto SRF, Franco CMR. Intermittent drying: fundamentals, modeling and applications. In J. M. P. Q. Delgado & A. G. Barbosa de Lima (Eds.), Drying and Energy Technologies 2016; 19–41. Cham: Springer International Publishing.
- Allaf K, Mounir S, Negm M, Allaf T, Ferrasse H, Mujumdar A. Intermittent Drying. In Arun S. Mujumdar, eds. Handbook of Industrial Drying, 4th ed, Boca Raton, Florida: CRC Press; 2015; 491–501
- Ferguson AR, Seal AG, Kiwifruit. In J. Hancock (Ed.), Temperate Fruit Crop Breeding 2014; 235–64. Springer Netherlands.
- Darıcı S, Şen S. Experimental investigation of convective drying kinetics of kiwi under different conditions. Heat Mass Trans 2015; 51(8): 1167–76. doi: 10.1007/s00231-014-1487-x.
- Tian Y, Wu S, Zhao Y, Zhang Q, Huang J, Zheng B. Drying characteristics and processing parameters for microwave-vacuum drying of Kiwifruit (Actinidia deliciosa) slices. J Food Process Preserv 2015; 39(6): 2620–9. doi: 10.1111/jfpp.12512.
- Orikasa T, Koide S, Okamoto S, Imaizumi T, Muramatsu Y, Takeda J.-i, Tagawa A. Impacts of hot air and vacuum drying on the quality attributes of kiwifruit slices. J Food Eng 2014; 125(0): 51–8. doi: http://dx.doi.org/10.1016/j.jfoodeng.2013.10.027.
- Kaya A, Aydın O, Kolaylı S. Effect of different drying conditions on the vitamin C (ascorbic acid) content of Hayard kiwifruits (Actinidia deliciosa Planch). Food Bioproducts Process 2010; 88(2–3): 165–73. http://dx.doi.org/10.1016/j.fbp.2008.12.001.
- Maskan M. Kinetics of colour change of kiwifruits during hot air and microwave drying. J Food Eng 2001; 48(2): 169–75. doi: http://dx.doi.org/10.1016/S0260-8774(00)00154-0.
- Joardder MUH, Brown RJ, Kumar C, Karim MA. Effect of cell wall properties on porosity and shrinkage of Dried Apple. Int J Food Properties 2015; 18(10): 2327–37. doi: 10.1080/10942912.2014.980945.
- Darvishi H, Zarein M, Farhudi Z. Energetic and exergetic performance analysis and modeling of drying kinetics of kiwi slices. J Food Sci Technol 2016; 53(5): 2317–33. doi: 10.1007/s13197-016-2199-7.
- Kaya A, Aydın O, Dincer I. Experimental and numerical investigation of heat and mass transfer during drying of Hayward kiwi fruits (Actinidia Deliciosa Planch). J Food Eng 2008; 88(3): 323–30. doi: 10.1016/j.jfoodeng.2008.02.017.
- Simal S, Femenia A, Garau MC, Rosselló C. Use of exponential, Page’s and diffusional models to simulate the drying kinetics of kiwi fruit. J Food Eng 2005; 66(3): 323–8. doi: https://doi.org/10.1016/j.jfoodeng.2004.03.025.
- Orikasa T, Wu L, Shiina T, Tagawa A. Drying characteristics of kiwifruit during hot air drying. J Food Eng 2008; 85(2): 303–8. http://dx.doi.org/10.1016/j.jfoodeng.2007.07.005.
- Benlloch-Tinoco M, Kaulmann A, Corte-Real J, Rodrigo D, Martínez-Navarrete N, Bohn T. Chlorophylls and carotenoids of kiwifruit puree are affected similarly or less by microwave than by conventional heat processing and storage. Food Chem 2015; 187: 254–62. doi: 10.1016/j.foodchem.2015.04.052.
- Fathi M, Mohebbi M, Razavi S. Application of image analysis and artificial neural network to predict mass transfer kinetics and color changes of osmotically dehydrated Kiwifruit. Food Bioprocess Technol 2011; 4(8): 1357–66. doi: 10.1007/s11947-009-0222-y.
- An K, Li H, Zhao D, Ding S, Tao H, Wang Z. Effect of osmotic dehydration with pulsed vacuum on hot-air drying kinetics and quality attributes of Cherry Tomatoes. Drying Technol 2013; 31(6): 698–706. doi: 10.1080/07373937.2012.755192.
- Huang D, Li W, Shao H, Gao A, Yang X. Colour, texture, microstructure and nutrient retention of Kiwifruit slices subjected to combined air-impingement jet drying and freeze drying. Int J Food Eng 2017; 13(7), doi: 10.1515/ijfe-2016-0344.
- Bhattacharya M, Srivastav PP, Mishra HN. Thin-layer modeling of convective and microwave-convective drying of oyster mushroom (Pleurotus ostreatus). J Food Sci Technol 2015; 52(4): 2013–22. doi: 10.1007/s13197-013-1209-2.
- Schossler K, Jager H, Knorr D. Effect of continuous and intermittent ultrasound on drying time and effective diffusivity during convective drying of apple and red bell pepper. J Food Eng 2012; 108(1): 103. doi: 10.1016/j.jfoodeng.2011.07.018.
- Asami DK, Hong Y-J, Barrett DM, Mitchell AE. Comparison of the total phenolic and ascorbic acid content of freeze-dried and air-dried marionberry, strawberry, and corn grown using conventional, organic, and sustainable agricultural practices. J Agric Food Chem 2003; 51(5): 1237–41. doi: 10.1021/jf020635c.
- Socha R, Juszczak L, Pietrzyk S, Fortuna T. Antioxidant activity and phenolic composition of herbhoneys. Food Chem 2009; 113(2): 568–74. doi: 10.1016/j.foodchem.2008.08.029.
- Sharifian F, Modarres-Motlagh A, Komarizade MH, Nikbakht AM. Colour change analysis of fig fruit during microwave drying. Int J Food Eng 2013; 9(1): 107–14. doi: 10.1515/ijfe-2012-0211.
- Khan MIH, Wellard RM, Pham ND, Karim A. Investigation of cellular level of water in plant-based food material. International Drying Symposium, 2016; 7–10. Gifu, Japan.
- Moreno JJ. Innovative processing technologies for foods with bioactive compounds. Milton: CRC Press; 2016.
- Sablani SS, Kasapis S, Rahman MS. Evaluating water activity and glass transition concepts for food stability. J Food Eng 2007; 78(1): 266–71. doi: 10.1016/j.jfoodeng.2005.09.025.
- Pittia P, Antonello P. Chapter 2 – safety by control of water activity: drying, smoking, and salt or sugar addition A2 – Prakash, Vishweshwaraiah. In: Martín-Belloso O, Keener L, Astley S, Braun S, McMahon H Lelieveld H. (Eds.), Regulating safety of traditional and ethnic foods. San Diego: Academic Press; 2016; 7–28.
- Junqueira JRDJ, Corrêa JLG, Ernesto DB. Microwave, convective, and intermittent microwave-convective drying of pulsed vacuum osmode-hydrated pumpkin slices. J Food Process Preserv 2017; 41(6): e13250. doi: doi:10.1111/jfpp.13250.
- Guldas M. Peeling and the physical and chemical properties of kiwi fruit. J Food Process Preserv 2003; 27(4): 271–84. doi: 10.1111/j.1745-4549.2003.tb00517.x.
- Vissers MCM, Carr AC, Pullar JM, Bozonet SM. Chapter seven – the bioavailability of vitamin C from Kiwifruit. In: Mike B, Paul JM, editors, Advances in food and nutrition research. San Diego: Academic Press; 2013; 68: 125–47.
- Joardder MUH, Brown RJ, Kumar C, Karim MA. Effect of cell wall properties on porosity and shrinkage of dried apple. Int J Food Properties 2015; 18(10): 2327–37. doi: 10.1080/10942912.2014.980945
- Aguilera J.M, Why food microstructure? J Food Eng 2005; 67(1): 3–11. doi: 10.1016/j.jfoodeng.2004.05.050.
- De Roos KB. Effect of texture and microstructure on flavour retention and release. Int Dairy J 2003; 13(8): 593–605. doi: http://dx.doi.org/10.1016/S0958-6946(03)00108-0.
- McSweeney M, Seetharaman K. State of polyphenols in the drying process of fruits and vegetables. Crit Rev Food Sci Nutr 2015; 55(5): 660–9. doi: 10.1080/10408398.2012.670673.
- Değirmencioğlu N, Gürbüz O, Herken EN, Yıldız AY. The impact of drying techniques on phenolic compound, total phenolic content and antioxidant capacity of oat flour tarhana. Food Chem 2016; 194: 587–94. doi: http://dx.doi.org/10.1016/j.foodchem.2015.08.065.
- Horuz E, Bozkurt H, Karatas¸ H, Maskan M. Effects of hybrid (microwave-convectional) and convectional drying on drying kinetics, total phenolics, antioxidant capacity, vitamin C, color and rehydration capacity of sour cherries. Food Chem 2017; 230: 295–305. doi: http://dx.doi.org/10.1016/j.foodchem.2017.03.046.
- Wang R, Ding S, Zhao D, Wang Z, Wu J, Hu X. Effect of dehydration methods on antioxidant activities, phenolic contents, cyclic nucleotides, and volatiles of jujube fruits. Food Sci Biotechnol 2016; 25(1): 137–43. doi: 10.1007/s10068-016-0021-y.
- Cangi R, Altuntas E, Kaya C, Saracoglu O. Some chemical and physical properties at physiological maturity and ripening period of kiwifruit (‘Hayward’). Afr J Biotechnol 2011; 10(27): 5304–10. doi: 10.5897/AJB11.192.
- Grabowski S, Marcotte M, Poirier M, Kudra T. Drying characteristics of osmotically pre-treated cranberries-energy and quality aspects*. Drying Technol 2007; 20(10): 1989–2004. doi: 10.1081/DRT-120015580.
- Reyes A, Alvarez PI, Marquardt FH. Drying of carrots in fluidized bed. I. Effect of drying conditions and modelling. Drying Technol 2002; 20(7): 1463–83. doi: 10.1081/DRT-120005862.
- Hansmann CF, Joubert E, Britz TJ. Dehydration of peaches without sulphur dioxide. Drying Technol 1998; 16(1–2): 101–21. doi: 10.1080/07373939808917394.
- Ho JC, Chou SK, Chua KJ, Mujumdar AS, Hawlader MNA. Analytical study of cyclic temperature drying: effect on drying kinetics and product quality. J Food Eng 2002; 51(1): 65–75. doi: 10.1016/S0260-8774(01)00038-3.
- Lewicki PP, Pawlak G. Effect of drying on microstructure of plant tissue. Drying Technol 2003; 21(4): 657–83. doi: 10.1081/DRT-120019057.
- Lewicki PP, Duszczyk E. Color change of selected vegetables during convective air drying. Int J Food Properties 1998; 1(3): 263–73. doi: 10.1080/10942919809524582.
- Fornal J. The changes of plant materials microstructure during processing. Polish J Food Nutr Sci 1998; 7(3): 9–23.
- Kowalski SJ, Pawłowski A. Energy consumption and quality aspect by intermittent drying. Chem Eng Process Process Intensific 2011; 50(4): 384–90. doi: 10.1016/j.cep.2011.02.012.
- Chaikham P, Kreungngern D, Apichartsrangkoon A. Combined microwave and hot air convective dehydration on physical and biochemical qualities of dried longan flesh. Int Food Res J 2013; 20(5): 2145–51.
- Kumar C, Joardder MUH, Karim A, Millar GJ, Amin Z. Temperature redistribution modelling during intermittent microwave convective heating. Procedia Engineering 2014; 90: 544–549. doi: https://doi.org/10.1016/j.proeng.2014.11.770.
This work is licensed under a Creative Commons Attribution 4.0 International License
Authors retain copyright of their work, with first publication rights granted to SNF Swedish Nutrition Foundation.