with the collaboration of Iranian Society of Mechanical Engineers (ISME)

Document Type : Research Article

Authors

1 PhD Student, Department of Biosystems Engineering, College of Agriculture, Isfahan University of Technology, Isfahan, Iran

2 Department of Biosystems Engineering, College of Agriculture, Isfahan University of Technology, Isfahan, Iran

Abstract

Introduction
Due to the disadvantages of using chemical materials as pretreatment before grape drying, the application of non-chemical methods that not only take the environmental issues into account but also increase the drying rate and improve the quality of the produced raisins is vitally important. The high-humidity hot air impingement blanching (HHAIB) is one of the non-chemical methods that can be used as a suitable alternative for chemical pretreatment in grape drying. In this research, the design, construction, and evaluation of a high-humidity hot air impingement blanching system are discussed in terms of the drying kinetics of white seedless grapes. The results are compared against the control and chemical pretreatment.
Materials and Methods
High-humidity hot air impingement blanching (HHAIB) system
The HHAIB system is composed of the steam generator, steam transfer pipes, side channel pump, closing and opening valves, air recycling channel, electric air heater, hot-humid air transfer channel, pretreatment chamber, hot-humid air distribution chamber, nozzles, temperature and humidity sensors and controllers. The performance of the system depends on the humid air temperature, the output fluid velocity from the nozzle, the distance of the nozzles from the product surface, as well as the diameter and arrangement of the nozzles. In order to achieve optimal design of the nozzle array, the relationships existed for the heat transfer coefficient, air mass flow, and blowing power were considered.
Application of the HHAIB pretreatment and evaluation of its effect on the grape drying process
Experiments were conducted to investigate the effect of temperature and duration of HHAIB pretreatment on the kinetics of grape drying. A two-factor completely randomized factorial design with three replications was used to analyze the data.
According to the studies, the air at temperatures of 90, 100, and 110°C, a velocity of 10 m s-1, and relative humidity in the range of 40-45% was applied to the product. Pretreatment durations of 30, 60, 90, 120, and 150 s were also considered. Experiments were conducted with three replicates and control treatment and acid pretreatment were used to compare the drying process. Due to the high quality of shade-dried raisins, this method was used to study the process.
The effect of the pretreatment duration on the drying kinetics of white seedless grapes was assessed by observing variations in moisture ratio and drying rate over time, as well as determining the effective diffusivity of water.
For the color evaluation of the produced raisins, chroma (C), hue angle H°, and total color difference (ΔE) parameters were calculated after measuring L*, a*, and b* values.
Results and Discussion
The comparison of the drying process among the control, chemical, and HHAIB showed the positive efficacy of HHAIB on the drying rate of grapes. Compared to fresh grapes, the increase in drying rate under the influence of HHAIB varied from 8% for a duration of 30 s at 90°C to 68% for a duration of 150 s at 110°C. The values of the diffusion coefficient of grapes for the HHAIB pretreatment at temperatures of 90, 100, and 110°C and durations of 30, 60, 90, 120, and 150 s, as well as for the control and chemical pretreatments were determined. The values of the coefficient changed from 2.28×10-10 m2 s-1 for 30 s of applying pretreatment at 90°C to 3.53×10-10 m2 s-1 for 150 s of applying the pretreatment at 110°C. The highest value of this coefficient (7.46×10-10 m2 s-1) was associated with the chemical pretreatment. The value of the diffusion coefficient increased with increasing temperature and duration of the HHAIB pretreatment. In general, this increase in the drying rate and the diffusion coefficient can be attributed to the effect of the HHAIB pretreatment on the texture and destruction of the cell wall, as well as the microcracks created on the skin of the grapes. Moreover, the findings reveal that, in comparison with the hot air temperature, the duration of the HHAIB pretreatment was more effective in enhancing the drying rate. Additionally, based on the color analysis, a temperature of 110°C and a duration range of 90-150 s were achieved as suitable conditions for applying pretreatment.
Conclusion
The HHAIB pretreatment, which combines the benefits of hot air blanching with jet technology, affects the texture and skin of grapes, accelerates the drying process, and increases the quality of the produced raisins. However, the correct application of this pretreatment depends on the proper design of the system and appropriate conditions, including duration, temperature, and relative humidity. The results of drying kinetics showed that the drying rate increased with an increase in the temperature and duration of the pretreatment. The findings indicate that the HHAIB pretreatment could improve the color indices of the raisins, resulting in an increase in the drying rate and acceptable quality of the final product. This provides a basis for the use of HHAIB on larger and industrial scales.

Keywords

Main Subjects

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  1. Ah-Hen, K., Zambra, C. E., Aguëro, J. E., Vega-Gálvez, A., & Lemus-Mondaca, R. (2013). Moisture diffusivity coefficient and convective drying modelling of murta (Ugni molinae Turcz): Influence of temperature and vacuum on drying kinetics. Food and Bioprocess Technology, 6(4), 919-930. https://doi.org/10.1007/s11947-011-0758-5
  2. Ayoubi, A., Sedaghat, N., & Kashaninejad, M. (2015). Study the effect of different pretreatments on thin layer drying of grape and the color of obtained raisin. Research and Innovation in Food Science and Technology, 4(1), 1-18. https://doi.org/10.22101/JRIFST.2015.05.10.411
  3. Bai, J. W., Sun, D. W., Xiao, H. W., Mujumdar, A., & Gao, Z. J. (2013). Novel high-humidity hot air impingement blanching (HHAIB) pretreatment enhances drying kinetics and color attributes of seedless grapes. Innovative Food Science & Emerging Technologies 20, 230-237. https://doi.org/10.1016/j.ifset.2013.08.011
  4. Bai, J. W., Gao, Z. J., Xiao, H. W., Wang, X. T., & Zhang, Q. (2013). Polyphenol oxidase inactivation and vitamin C degradation kinetics of F uji apple quarters by high humidity air impingement blanching. International Journal of Food Science & Technology, 48(6), 1135-1141. https://doi.org/10.1111/j.1365-2621.2012.03193.x
  5. Crank, J. (1979). The mathematics of diffusion. Oxford university press.
  6. Dai, J. W., Wang, J., Yang, S. L., Wen, M. D., Yin, P. F., Qin, W., Liu, Y. W., Liu, Q., Liu, S. X., & Xu, L. J. (2020). High humidity air-impingement blanching (HHAIB) improves drying characteristics and quality of ground-cover chrysanthemum heads. International Journal of Food Engineering, 16(12). https://doi.org/10.1515/ijfe-2020-0121
  7. De Roeck, A., Sila, D. N., Duvetter, T., Van Loey, A., & Hendrickx, M. (2008). Effect of high pressure/high temperature processing on cell wall pectic substances in relation to firmness of carrot tissue. Food Chemistry, 107(3), 1225-1235. https://doi.org/10.1016/j.foodchem.2007.09.076
  8. Dehbooreh, R., & Esmaiili, M. (2009). Evaluation of Microwave and Convective Finish Drying Parameters and Drying Effects on Color of Dried Grapes. Iranian Food Science and Technology Research Journal, 5(2). https://doi.org/10.1590/1678-4324-2022210614
  9. Deng, L. Z., Mujumdar, A., Yang, X. H., Wang, J., Zhang, Q., Zheng, Z. A., Gao, Z. J., & Xiao, H. W. (2018). High humidity hot air impingement blanching (HHAIB) enhances drying rate and softens texture of apricot via cell wall pectin polysaccharides degradation and ultrastructure modification. Food Chemistry, 261, 292-300. https://doi.org/10.1016/j.foodchem.2018.04.062
  10. Dev, S., Padmini, T., Adedeji, A., Gariépy, Y., & Raghavan, G. (2008). A comparative study on the effect of chemical, microwave, and pulsed electric pretreatments on convective drying and quality of raisins. Drying Technology, 26(10), 1238-1243. https://doi.org/10.1080/07373930802307167
  11. Di Matteo, M., Cinquanta, L., Galiero, G., & Crescitelli, S. (2000). Effect of a novel physical pretreatment process on the drying kinetics of seedless grapes. Journal of Food Engineering, 46(2), 83-89. https://doi.org/10.1016/S0260-8774(00)00071-6
  12. Doulati Baneh, H. (2016). the Grapevine Comperhensive Management of Growling, Production and Processing: University of Kurdistan Press.
  13. Earle, R. L. (2013). Unit operations in food processing. Elsevier.
  14. Gao, Z., Xiao, H., Liu, B., & Yang, W. (2008). A no nutritional loss and non-fried sweet potato chips processing method. China Patent No. ZL200810116897
  15. Jayaprakasha, G. K., Singh, R. P., & Sakariah, K. K. (2001). Antioxidant activity of grape seed (Vitis vinifera) extracts on peroxidation models in vitro. Food Chemistry, 73(3), 285-290. https://doi.org/10.1016/S0308-8146(00)00298-3
  16. Kondjoyan, A., Chevolleau, S., Grève, E., Gatellier, P., Santé-Lhoutellier, V., Bruel, S., Touzet, C., Portanguen, S., & Debrauwer, L. (2010). Formation of heterocyclic amines in slices of Longissimus thoracis beef muscle subjected to jets of superheated steam. Food Chemistry, 119(1), 19-26. https://doi.org/10.1016/j.foodchem.2009.02.081
  17. Liu, Z. L., Bai, J. W., Yang, W. X., Wang, J., Deng, L. Z., Yu, X. L., Zheng, Z. A., Gao, Z. J., & Xiao, H. W. (2019). Effect of high-humidity hot air impingement blanching (HHAIB) and drying parameters on drying characteristics and quality of broccoli florets. Drying Technology. https://doi.org/10.1080/07373937.2018.1494185
  18. Madamba, P. S., Driscoll, R. H., & Buckle, K. A. (1996). The thin-layer drying characteristics of garlic slices. Journal of Food Engineering, 29(1), 75-97. https://doi.org/10.1016/0260-8774(95)00062-3
  19. Martin, H. (1977). Heat and mass transfer between impinging gas jets and solid surfaces in. Advances in heat transfer (vol. 13). (pp. 1-60) Elsevier.
  20. Moelants, K. R., Cardinaels, R., Van Buggenhout, S., Van Loey, A. M., Moldenaers, P., & Hendrickx, M. E. (2014). A review on the relationships between processing, food structure, and rheological properties of plant‐tissue‐based food suspensions. Comprehensive Reviews in Food Science and Food Safety, 13(3), 241-260. https://doi.org/10.1111/1541-4337.12059
  21. Olsson, E., Trägårdh, A., & Ahrné, L. (2005). Effect of near‐infrared radiation and jet impingement heat transfer on crust formation of bread. Journal of Food Science, 70(8), e484-e491. https://doi.org/10.1111/j.1365-2621.2005.tb11519.x
  22. Rico, D., Martín-Diana, A. B., Barry-Ryan, C., Frías, J. M., Henehan, G. T., & Barat, J. M. (2008). Optimisation of steamer jet-injection to extend the shelflife of fresh-cut lettuce. Postharvest Biology and Technology, 48(3), 431-442. https://doi.org/10.1016/j.postharvbio.2007.09.013
  23. Sarkar, A., & Singh, R. P. (2004). Air impingement technology for food processing: visualization studies. LWT-Food Science and Technology, 37(8), 873-879. https://doi.org/10.1016/j.lwt.2004.04.005
  24. Schabel, W., & Martin, H. (2010). G10 Impinging jet flow heat transfer in. VDI Heat Atlas.
  25. Sui, M., Gao, Z., Ni, Z., & Fang, X. (2008). Study on relationship of temperature and puffing in roasting process of Peking duck with air impingement. Journal of Food Science and Technology (China), 10, 68-70.
  26. Swati, K., & Ashim, D. (2014). Modeling Mechanical Property Changes During Heating of Carrot Tissue -A Microscale Approach. COMSOL Conference. Boston.
  27. Thorat, I. D., Mohapatra, D., Sutar, R., Kapdi, S., & Jagtap, D. D. (2012). Mathematical modeling and experimental study on thin-layer vacuum drying of ginger (Zingiber officinale) slices. Food and Bioprocess Technology, 5(4), 1379-1383. https://doi.org/10.1007/s11947-010-0429-y
  28. Wang, H., Xiao, H. W., Liu, Z. L., Yu, X. L., Zhu, G. F., & Zheng, Z. (2019). Effect of drying and high-humidity hot air impingement blanching (HHAIB) parameters on drying characteristics and quality of apple slices. Pages 1. 2019 ASABE Annual International Meeting: American Society of Agricultural and Biological Engineers. https://doi:10.13031/aim.201900524
  29. Wang, J., Fang, X. M., Mujumdar, A., Qian, J. Y., Zhang, Q., Yang, X. H., Liu, Y. H., Gao, Z. J., & Xiao, H. W. (2017a). Effect of high-humidity hot air impingement blanching (HHAIB) on drying and quality of red pepper (Capsicum annuum). Food Chemistry, 220, 145-152. https://doi.org/10.1016/j.foodchem.2016.09.200
  30. Wang, J., Mu, W. S., Fang, X. M., Mujumdar, A., Yang, X. H., Xue, L. Y., Xie, L., Xiao, H. W., Gao, Z. J., & Zhang, Q. (2017b). Pulsed vacuum drying of Thompson seedless grape: Effects of berry ripeness on physicochemical properties and drying characteristic. Food and Bioproducts Processing, 106, 117-126. https://doi.org/10.1016/j.fbp.2017.09.003
  31. Xiao, H. W., Pang, C. L., Wang, L. H., Bai, J. W., Yang, W. X., & Gao, Z. J. (2010). Drying kinetics and quality of Monukka seedless grapes dried in an air-impingement jet dryer. Biosystems Engineering, 105(2), 233-240. https://doi.org/10.1016/j.biosystemseng.2009.11.001
  32. Xiao, H. W., & Mujumdar, A. (2014). Impingement Drying: Application and Future Trends.
  33. Xiao, H. W., Yao, X. D., Lin, H., Yang, W. X., Meng, J. S., & Gao, Z. J. (2012). Effect of SSB (superheated steam blanching) time and drying temperature on hot air impingement drying kinetics and quality attributes of yam slices. Journal of Food Process Engineering, 35(3), 370-390. https://doi.org/10.1111/j.1745-4530.2010.00594.x
  34. Zielinska, S., Cybulska, J., Pieczywek, P., Zdunek, A., Kurzyna-Szklarek, M., Liu, Z. L., Staniszewska, I., Pan, Z., Xiao, H. W., & Zielinska, M. (2022). The effect of high humidity hot air impingement blanching on the changes in molecular and rheological characteristics of pectin fractions extracted from okra pods. Food Hydrocolloids, 123, 107199. https://doi.org/10.1016/j.foodhyd.2021.107199
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