Investigating the drying parameters of Fijou fruit in a freeze dryer

Document Type : Research Article


1 Assistant professor, Department of Mechanics of Biosystem Engineering, Sari Agricultural Sciences and Natural Resources University, Sari, Iran

2 Associate professor, Department of Mechanics of Biosystem Engineering, Sari Agricultural Sciences and Natural Resources University, Sari, Iran


Freeze drying is one of the best methods for the removal of water in temperature sensitive agricultural products. In the present study was investigated the process of drying the Fijou fruit in a freeze dryer under the influence of different pretreatments and were calculated the moisture diffusion coefficients (mass transfer coefficient) by using of Dincer and Dost models and Fick’s model, drying rate constant, convective mass transfer coefficient, specific energy consumption and specific moisture extraction ratio. Various pre-treatments applied to the samples are ascorbic acid (with 1% concentration and 1, 2 and 3 min), microwave (with 90 W for 10 min, 180 W for 5 min and 360 W for 2.5 min), blanching with hot water and steam (with 1, 2 and 3 min), potassium carbonate (with 2.5% concentration and 1, 2 and 3 min), osmotic (with 45% sucrose concentration and 10, 20 and 30 min), and ultrasound (with 10, 20 and 30 min). The highest drying rate constant and convective mass coefficient were obtained in microwave pre-treatment to 0.0073 (s-1) and 2.900×10-5 (m2/s), respectively. The range of moisture diffusion coefficients was variable in Fick’s model from 0.7404×10-8 to 1.3996×10-8 (m2/s) and for Dincer and Dost model from 4.5318×10-7 to 9.2149×10-7 (m2/s). The highest and lowest specific energy requirements were 47.23 and 23.61 kWh/kg in osmotic and microwave pre-treatment, respectively. Also the highest and lowest specific moisture extraction ratio were 0.0423 and 0.0212 kg/kWh in microwave and osmotic pre-treatment, respectively.

Graphical Abstract

Investigating the drying parameters of Fijou fruit in a freeze dryer


  • In the present study the Fijou fruit was dried in a freeze dryer under seven different pretreatments.
  • The highest drying rate constant was obtained in microwave pre-treatment to 0.0073 s-1.
  • The highest convective mass coefficient was obtained in microwave pre-treatment to 2.900×10-5 m2/s.
  • The highest specific energy consumption was obtained in osmotic pre-treatment 47.23 kg/kWh.
  • Among different pretreatments, the use of microwave had the best result in terms of mass transfer and energy consumption.


Main Subjects

[1] Weston, R.Y. (2010). Bioactive products from fruit of the Feijoa (Feijoa sellowiana, Myrtaceae): a review. Food Chem., 121, 9, 23–926.
[2] Hardy, P.J., Michael, B.J. (1970). Volatile components of Feijoa Fruits. Phytochem., 9, 1355–1357.
[3] Talens, P., Chirlat, A., Martinez, N., Fito, P. (2002). Changes in optical and mechanical properties during osmodehydrofreezing of kiwi fruit. Innov. Food Sci. Emerging Technol., 3 (2), 191-199.
[4] Woo, M.W., Mujumdar, A.S. (2010). Effects of electric and magnetic field on freezing and possible relevance in freeze drying. Drying Technol., 28 (4), 433-443.
[5] Tregunno, N. B., Goff, H. D. (2018). Osmodehydrofreezing of apples: structural and textural effects. Food Res. Int. 29 (5-6), 471-479.
[6] Ren, F., Perussello, C.A., Zhang, Z., Kerry, J.P., Tiwari, B.K. (2017). Impact of ultrasound and blanching on functional properties of hot-air dried and freeze dried onions, LWT–Food Sci. Technol. doi: 10.1016/j.lwt.2017.08.053.
[7] Motevali, A., Hashemi, S.J. (2017). The Effect of Different Pre-treatments on Qualitative Properties of Freeze-dried Feijoa Fruit. Chinese J. Chem. Eng.,
[8] Acar, B., Sadikoglu, H., I Doymaz, I. (2014). Freeze-drying kinetics and diffusion modeling of saffron (crocus sativus l.). J. Food Process Pres., 39 (2), 142-149.
[9] Jiang, N., Zhang, Z., Li, D., Liu, C., Zhang, M., Liu, C., Wang, D., Niu, L. (2017). Evaluation of freeze drying combined with microwave vacuum drying for functional okra snacks: Antioxidant properties, sensory quality, and energy consumption, LWT - Food Sci. Technol., doi: 10.1016/j.lwt.2017.04.015.
[10] Prosapio, V., Norton I. (2017). Influence of osmotic dehydration pre-treatment on oven drying and freeze drying performance. LWT - Food Sci. Technol. 80, 401-408.
[11] Colucci, D., Fissore, D., Rossello, C., Carcel, J .A. (2017). On the effect of ultrasound-assisted atmospheric freeze-drying on the antioxidant properties of eggplant. Food Res. Int.
[12] Lenaerts, S., Van Der Borght, M., Callens, A., Van Campenhout, L. (2018). Suitability of microwave drying for mealworms (Tenebrio molitor) as alternative to freeze drying: Impact on nutritional quality and colour. Food Chem. 254, 129-136.
[13] Wang, W., Yang, J., Hu, D., Pan, Y., Wang, S., Chen G. (2018). Experimental and numerical investigations on freeze-drying of­ porous media with prebuilt porosity. Chem. Physics Letters, doi:
[14] Alfat, S., Purqon, A. (2017). Heat and Mass Transfer Model in Freeze-Dried. Medium J. Phys.: Conf. Ser. 877, 012061
[15] Cao, X., Zhang, M., Mujumdar, A. S., Zhong, Q., Wang, Z. (2017). Effects of ultrasonic pretreatments on quality, energy consumption and sterilization of barley grass in freeze drying, Ultras. Sonochem., doi:
[16] Kırmacı,V., Usta, H., Menlik, T. (2008). An Experimental Study on Freeze-Drying Behavior of Strawberries, Drying Technol., 26, 12, 1570-1576.
[17] Silveira, A.M., Freire, J.T. (2006). Freeze-Drying Characteristics of Tropical Fruits, Drying Technol., 24, 4, 457-463.
[18] Muthukumaran, A., Ratti, C., Raghavan, V.G.S. (2008). Foam-Mat Freeze Drying of Egg White-Mathematical Modeling Part II: Freeze Drying and Modeling, Drying Technol., 26, 513–518.
[19] Rafiee, S., Keyhani, A. and jafari, A. (2008). Modeling effective moisture diffusivity of wheat (Tajan) during air drying. Int. J. Food Properties, 11, 1–10.
[20] Dincer, I. (1998). Moisture transfer analysis during drying of slab woods. Heat Mass Trans., 34, 317-320.
[21] Torki-Harchegani, M., Ghanbarian, D., Maghsoodi, V., Moheb, A. (2017). Infrared thin layer drying of saffron (Crocus sativus L.) stigmas: Mass transfer parameters and quality assessment. Chinese J. Chem. Eng., 25, 426-432.
[22] Dincer, I., Hussain M.M. (2002). Development of a new Bi–Di correlation for solids drying. Int. J. of Heat Mass Trans. 45, 3065–3069.
[23] Dincer, I., Dost S. (1995). An analytical model for moisture diffusion in solid objects during drying, Drying Technol. 13 (1&2), 425–435.
[24] Wang, Z., Sun, J., Liao, X., Chen, F., Zhao, G., Wu, J., & Hu, X. 2007.  Mathematical modeling on hot air drying of thin layer apple pomace. Food Res. Int., 40: 39-46.
[25] Sacilic, K., Elicin, A. 2006.  Mathematical modeling of solar tunnel drying of thin layer organic tomato. J. Food Eng., 173: 231-238.
[26] Doymaz, I. 2004.  Drying kinetics of white mulberry. J. Food Eng., 61: 341-346.
[27] Chapchaimoh, K., Poomsa-ad, N., Wiset, L., Morris, J., (2016). Thermal characteristics of heat pump dryer for ginger drying. App. Thermal Eng., 95, 491–498.
[28] Aktas, M., Khanlari, A., Amini, A., Sevik, S. (2017). Performance analysis of heat pump and infrared–heat pump drying of grated carrot using energy-exergy methodology. Energy Conv. Manag., 132, 327–338
[29] Motevali, A.,  Hedayati, F. (2017). Investigation of change Drying Rate Constant coefficient in simulations models with various pretreatments on drying apple. J. Innov. Food Technol., 4 (3), 39-51. (In Persian).
[31] Toyosi, Y., Tunde-Akintunde, Grace O. Ogunlakin. (2011). Influence of drying conditions on the effective moisture diffusivity and energy requirements during the drying of pretreated and untreated pumpkin. Energy Conv. Manag. 52, 1107–1113.
[32] Adedeji, A. A., Gachovska,T. K., Ngadi , M. O., Raghavan, G. S. V. (2008). Effect of Pretreatments on Drying Characteristics of Okra. Drying Technol., 26, 10, 1251-1256.
[33] Darıcı, S., Şen, S. (2015). Experimental investigation of convective drying kinetics of kiwi under different conditions. Heat Mass Trans., 51 (8), 1167-1176
[34] Liu, X., Hou, H., Chen J. (2013). Applicability of moisture transfer parameters estimated by correlation between Biot number and lag factor (Bi–G correlation) for convective drying of eggplant slices. Heat Mass Transf., 49 (11), 1595-1601.