Food and Bioprocess Technology

, Volume 11, Issue 6, pp 1236–1247 | Cite as

Dielectric Pretreatment of Rapeseed 1: Influence on the Drying Characteristics of the Seeds and Physico-chemical Properties of Cold-Pressed Oil

  • Baoguo Xu
  • Benxi Wei
  • Xiaofeng Ren
  • Yaogang Liu
  • Hao Jiang
  • Cunshan Zhou
  • Haile Ma
  • Meram Chalamaiah
  • Qiufang Liang
  • Zhirong Wang
Original Paper


The aim of this study was to explore the effect of dielectric pretreatments on the drying characteristics of rapeseeds and physico-chemical attributes of cold-pressed rapeseed oil. Rapeseeds were adjusted to moisture contents of 15% and underwent dielectric pretreatments prior to oil extraction by cold pressing at frequencies of 27, 915, and 2450 MHz for 45, 30, and 22 min, respectively. Results showed that 2450 MHz dielectric heating had the highest temperature rising rate but the most nonuniform temperature distribution. Compared to the control samples, oil extraction yields were increased by 12.28, 17.25, and 22.08% for 27, 915, and 2450 MHz dielectric pretreatments, respectively. The SEM analysis indicated that the cell structures of pretreated rapeseed samples were severely damaged, thereby improving the extraction efficiency. Additionally, dielectric pretreatments significantly increased the total tocopherol content and improved the oxidative stability of cold-pressed oil (p < 0.05). The oil extracted from the 27-MHz pretreated rapeseeds exhibited lower acid and peroxide values and less color change, indicating better quality is achieved. Regarding fatty acid (FA) composition of the oils, oleic acid slightly increased and docosenoic acid decreased, but the total FA composition was not altered significantly by dielectric pretreatments (p > 0.05). These results suggested that dielectric pretreatment, a promising and environment-friendly technique, could be useful in the food industry for oil extraction.


Dielectric Radio frequency Microwave Oxidative stability Tocopherol 


Funding Information

The authors wish to express their appreciation for the support obtained from the Key Research and Development Program of Jiangsu Province (Grant No. BE2016334), Natural Science Foundation of Jiangsu Province, China (Grant Nos. BK20170538 and BK20170534), and China Postdoctoral Science Foundation (Grant Nos. 2016M601742 and 2017M611738). The authors also are grateful to the National Natural Science Foundation of China (Grant No. 31501427), Foundation of Key Laboratory of Agricultural Products Physical Processing in Jiangsu Province (JAPP2014-3), the Senior Professional Research Start-up Fund of Jiangsu University (14JDG180), Young Backbone Teachers Program of Jiangsu University, the Nature Science Foundation of the Jiangsu Provincial Education Department (11KJB550001), and Priority Academic Program Development of Jiangsu Higher Education Institutions (PAPD).


  1. Alfaifi, B., Wang, S., Tang, J., Rasco, B., Sablani, S., & Jiao, Y. (2013). Radio frequency disinfestation treatments for dried fruit: dielectric properties. LWT - Food Science and Technology, 50(2), 746–754.CrossRefGoogle Scholar
  2. Anjuma, F., Anwara, F., Jamila, A., & Iqbal, M. (2006). Microwave roasting effects on the physico-chemical composition and oxidative stability of sunflower seed oil. Journal of the American Oil Chemists’ Society, 83(9), 777–784.CrossRefGoogle Scholar
  3. Azadmard-Damirchi, S., Habibi-Nodeh, F., Hesari, J., Nemati, M., & Achachlouei, B. F. (2010). Effect of pretreatment with microwaves on oxidative stability and nutraceuticals content of oil from rapeseed. Food Chemistry, 121(4), 1211–1215.CrossRefGoogle Scholar
  4. Azlan, A., Prasad, K. N., Khoo, H. E., Abdul-Aziz, N., Mohamad, A., Ismail, A., & Amom, Z. (2010). Comparison of fatty acids, vitamin E and physicochemical properties of Canarium odontophyllum Miq. (dabai), olive and palm oils. Journal of Food Composition & Analysis, 23(8), 772–776.CrossRefGoogle Scholar
  5. Ben, T. S., Taamalli, W., Baccouri, B., Abaza, L., Daoud, D., & Zarrouk, M. (2006). Changes in olive oil quality of Che′ toui variety according to origin of plantation. Journal of Food Lipids, 13(1), 88–99.CrossRefGoogle Scholar
  6. Coronel, P., Simunovic, J., Sandeep, K. P., Cartwright, G. D., & Kumar, P. (2008). Sterilization solutions for aseptic processing using a continuous flow microwave system. Journal of Food Engineering, 85(4), 528–536.CrossRefGoogle Scholar
  7. Da Porto, C., Decorti, D., & Natolino, A. (2016). Microwave pretreatment of Moringa oleifera seed: effect on oil obtained by pilot-scale supercritical carbon dioxide extraction and Soxhlet apparatus. The Journal of Supercritical Fluids, 107, 38–43.CrossRefGoogle Scholar
  8. Dolde, D., Vlahakis, C., & Hazebroek, J. (1999). Tocopherols in breeding lines and effects of planting location, fatty acid composition, and temperature during development. Journal of the American Oil Chemists’ Society, 76(3), 349–355.CrossRefGoogle Scholar
  9. Febrianto, N. A., & Yang, T. A. (2011). Producing high quality edible oil by using eco-friendly technology: a review. Advance Journal of Food Science & Technology, 3(4), 317–326.Google Scholar
  10. García-Moreno, P. J., Guadix, A., Gómez-Robledo, L., Melgosa, M., & Guadix, E. M. (2013). Optimization of bleaching conditions for sardine oil. Journal of Food Engineering, 116(2), 606–612.CrossRefGoogle Scholar
  11. Hafez, Y. S., Singh, G., Mclellan, M. E., & Monroe-Lord, L. (1983). Effects of microwave heating on nutritional quality of soybeans. Nutrition Reports International, 28, 413–421.Google Scholar
  12. Hassanein, M. M., ElShami, S. M., & Elmallah, H. (2003). Changes occurring in vegetable oils composition due to microwave heating. Grasas y Aceites, 54(4), 343–349.CrossRefGoogle Scholar
  13. Husain, S. R., Terao, J., & Matsushita, S. (1986). Effect of browning reaction products of phospholipids on autoxidation of methyl linoleate. Journal of the American Oil Chemists’ Society, 63(11), 1457–1460.CrossRefGoogle Scholar
  14. Jangam, S. V. (2010). An overview of recent developments and some R&D challenges related to drying of foods. Drying Technology, 29(12), 1343–1357.CrossRefGoogle Scholar
  15. Jiang, H., Zhang, M., Fang, Z., Mujumdar, A. S., & Xu, B. (2016). Effect of different dielectric drying methods on the physic-chemical properties of a starch–water model system. Food Hydrocolloids, 52, 192–200.CrossRefGoogle Scholar
  16. Jiang, H., Zhang, M., Mujumdar, A. S., & Lim, R.-X. (2012). Analysis of temperature distribution and SEM images of microwave freeze drying banana chips. Food and Bioprocess Technology, 6(5), 1144–1152.CrossRefGoogle Scholar
  17. Koubaa, M., Mhemdi, H., Barba, F. J., Roohinejad, S., Greiner, R., & Vorobiev, E. (2016). Oilseed treatment by ultrasounds and microwaves to improve oil yield and quality: an overview. Food Research International, 85, 59–66.CrossRefGoogle Scholar
  18. Ku, C. S., & Mun, S. P. (2008). Characterization of seed oils from fresh Bokbunja (Rubus coreanus Miq.) and wine processing waste. Bioresource Technology, 99(8), 2852–2856.CrossRefGoogle Scholar
  19. Li, J., Zu, Y. G., Luo, M., Gu, C. B., Zhao, C. J., Efferth, T., & Fu, Y. J. (2013). Aqueous enzymatic process assisted by microwave extraction of oil from yellow horn (Xanthoceras sorbifolia Bunge.) seed kernels and its quality evaluation. Food Chemistry, 138(4), 2152–2158.CrossRefGoogle Scholar
  20. Ling, B., Guo, W., Hou, L., Li, R., & Wang, S. (2015a). Dielectric properties of pistachio kernels as influenced by frequency, temperature, moisture and salt content. Food & Bioprocess Technology, 8(2), 420–430.CrossRefGoogle Scholar
  21. Ling, B., Tiwari, G., & Wang, S. (2015b). Pest control by microwave and radio frequency energy: dielectric properties of stone fruit. Agronomy for Sustainable Development, 35(1), 233–240.CrossRefGoogle Scholar
  22. Megahed, M. G. (2001). Microwave roasting of peanuts: effects on oil characteristics and composition. Nahrung/Food, 45(4), 255–257.CrossRefGoogle Scholar
  23. Oberndorfer, C., & Lücke, W. (1999). The effect of rapeseed treatment by microwave and radio-frequency application on oil extraction and oil quality. Part I_ influence on mechanical oil extraction. Fett/Lipid, 101(5), 164–167.CrossRefGoogle Scholar
  24. Qu, X.-J., Fu, Y.-J., Luo, M., Zhao, C.-J., Zu, Y.-G., Li, C.-Y., Wang, W., Li, J., & Wei, Z.-F. (2013). Acidic pH based microwave-assisted aqueous extraction of seed oil from yellow horn (Xanthoceras sorbifolia Bunge.) Industrial Crops and Products, 43, 420–426.CrossRefGoogle Scholar
  25. Rdelos, R., Heredia, A., Fito, P., Edelos, R., & Andres, A. (2007). Dielectric spectroscopy of osmotic solutions and osmotically dehydrated tomato products. Journal of Food Engineering, 80(4), 1218–1225.CrossRefGoogle Scholar
  26. Roebuck, B. D., Goldblith, S. A., & Westphal, W. B. (1972). Dielectric properties of carbohydrate-water mixtures at microwave frequencies. Journal of Food Science, 37(2), 199–204.CrossRefGoogle Scholar
  27. Starmans, D., & Nijhuis, H. H. (1996). Extraction of secondary metabolites from plant material: a review. Trends in Food Science & Technology, 7(6), 191–197.CrossRefGoogle Scholar
  28. Uquiche, E., Jeréz, M., & Ortíz, J. (2008). Effect of pretreatment with microwaves on mechanical extraction yield and quality of vegetable oil from Chilean hazelnuts (Gevuina avellana Mol). Innovative Food Science & Emerging Technologies, 9(4), 495–500.CrossRefGoogle Scholar
  29. 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.CrossRefGoogle Scholar
  30. Wang, Y., Zhang, M., Mujumdar, A. S., Mothibe, K. J., & Roknul, S. M. A. (2013). Study of drying uniformity in pulsed spouted microwave–vacuum drying of stem lettuce slices with regard to product quality. Drying Technology, 31(1), 91–101.CrossRefGoogle Scholar
  31. Wroniak, M., Rękas, A., Siger, A., & Janowicz, M. (2016). Microwave pretreatment effects on the changes in seeds microstructure, chemical composition and oxidative stability of rapeseed oil. LWT - Food Science and Technology, 68, 634–664.CrossRefGoogle Scholar
  32. Xu, B., Zhang, M., & Bhandari, B. (2014). Temperature and quality characteristics of infrared radiation–dried kelp at different peak wavelengths. Drying Technology, 32(4), 437–446.CrossRefGoogle Scholar
  33. Xu, B., Zhang, M., Xing, C., Mothibe, K. J., & Zhu, C. (2013). Composition, characterisation and analysis of seed oil of Suaeda salsa L. International Journal of Food Science & Technology, 48(4), 879–885.CrossRefGoogle Scholar
  34. Yang, M., Huang, F., Liu, C., Zheng, C., Zhou, Q., & Wang, H. (2012). Influence of microwave treatment of rapeseed on minor components content and oxidative stability of oil. Food and Bioprocess Technology, 6(11), 3206–3216.CrossRefGoogle Scholar
  35. Yang, M., Zheng, C., Zhou, Q., Liu, C., Li, W., & Huang, F. (2014). Influence of microwaves treatment of rapeseed on phenolic compounds and canolol content. Journal of Agricultural and Food Chemistry, 62(8), 1956–1963.CrossRefGoogle Scholar
  36. Yoshida, H., & Kajimoto, G. (1994). Microwave heating affects composition and oxidative stability of sesame (Sesamum indicum) oil. Journal of Food Science, 59(3), 613–616.CrossRefGoogle Scholar
  37. Zhang, M., Jiang, H., Lim, R., Silva, M. A., & Rocha, S. (2011). Recent developments in microwave-assisted drying of vegetables, fruits, and aquatic products—drying kinetics and quality considerations. Drying Technology, 28(11), 1307–1316.CrossRefGoogle Scholar
  38. Zhang, S., Zhou, L., Ling, B., & Wang, S. (2016). Dielectric properties of peanut kernels associated with microwave and radio frequency drying. Biosystems Engineering, 145, 108–117.CrossRefGoogle Scholar
  39. Zhou, Q., Yang, M., Huang, F., Zheng, C., & Deng, Q. (2013). Effect of pretreatment with dehulling and microwaving on the flavor characteristics of cold-pressed rapeseed oil by GC-MS-PCA and electronic nose discrimination. Journal of Food Science, 78(7), C961–C970.CrossRefGoogle Scholar
  40. Zhu, X., Guo, W., Wu, X., & Wang, S. (2012). Dielectric properties of chestnut flour relevant to drying with radio-frequency and microwave energy. Journal of Food Engineering, 113(1), 143–150.CrossRefGoogle Scholar

Copyright information

© Springer Science+Business Media, LLC, part of Springer Nature 2018

Authors and Affiliations

  1. 1.School of Food and Biological EngineeringJiangsu UniversityZhenjiangChina
  2. 2.Golden Sun Grain and Oil Company LtdNantongChina
  3. 3.School of Food Science and EngineeringNorthwest A&F UniversityYanglingChina
  4. 4.Department of Agricultural, Food and Nutritional Science (AFNS), 4-10 Ag/For CentreUniversity of AlbertaEdmontonCanada

Personalised recommendations