Drying characteristics of jujube (Zizyphus jujuba) slices in a hot air dryer and physicochemical properties of jujube powder

  • Feyza Elmas
  • Emine Varhan
  • Mehmet KoçEmail author
Original Paper


The hot air convective drying characteristics of sliced jujube fruits were investigated. Drying experiments were carried out at three different temperatures (60, 70 and 80 °C) and three different air velocity (0.5, 1.0, 1.5 m·s−1). All drying experiments had only falling rate period. The average effective diffusivity values varied from 1.2 × 10−9 to 3.55 × 10−9 m2·s−1 over the temperature and velocity range studied and the activation energy was estimated to be 28.183 kJ·mol−1 by modified Arrhenius Equation. In order to select a suitable form of the drying curve, seven different thin layer drying model was investigated and Page and Wangh and Singh models were considered the best to explain the drying of the jujube slices. Also, the influence of varied drying temperatures and velocity were investigated on physicochemical properties of the jujube powder. It was observed that moisture content and water activity values, which are an important powder product property, decrease with increasing temperature. It was found that the powder product obtained has different particle properties depending on the air temperature and velocity and therefore has different bulk and reconstitution properties. Within the scope of chemical analyzes, it was observed that the sugar content of the powder products is considerably high due to low moisture content. Also, according to the total phenolic content analysis, the higher temperature resulted in the lower total phenolic content.


Jujube Powder Drying kinetic Hot air drying Flowability Sugar content 



Short-medium infrared drying


Hot air drying


Moisture content (kg water·kg dry matter−1)


Dimensionless moisture content


Biot number


Effective diffusivity (m2·s−1)


Distance for diffusion (m).


Drying time (s).


Initial moisture content (kg water·kg dry matter−1)


Surface moisture content (kg water·kg dry matter−1)


Equilibrium moisture content (kg water·kg dry matter−1)


Convective mass transfer coefficient (m·s−1)


Thickness of slab (m)


Pre-exponential factor of the Arrhenius equation (m2·s−1)


Activation energy (kJ·mol−1)


Universal gas constant (kJ·mol−1·K−1)


Absolute air temperature (K)


Velocity of dryer air (m·s−1)


Root mean square error


De Brouckere mean diameter


Pycnometer weight (g) filled with powder product


Empty pycnometer weight (g)


Density of 2-propanol (0.785 g·ml−1)


Particle density of powder (kg m−3)


Pycnometer weight filled with 2-propanol (g)


Pycnometer weight filled powder product and 2-propanol (g)


Bulk density of powder (kg.m−3)


Tapped density of powder (kg.m−3)


Carr index


Refractive index detector


  1. 1.
    J.W. Li, S.D. Ding, X.L. Ding, Comparison of antioxidant capacities of extracts from five cultivars of Chinese jujube. Process Biochem. 40, 3607–3613 (2005)CrossRefGoogle Scholar
  2. 2.
    J. Li, L. Fan, S. Ding, X. Ding, Nutritional composition of five cultivars of Chinese jujube. Food Chem. 103, 454–460 (2007)CrossRefGoogle Scholar
  3. 3.
    K.K. Anand, B. Singh, D. Chand, B.K. Chandan, V.N. Gupta, Effect of Zizyphus sativa leaves on blood glucose levels in normal and alloxan-diabetic rat. J. Ethnopharmacol. 27, 121–127 (1989)CrossRefGoogle Scholar
  4. 4.
    R. Belford, Chinese herbal medicine treatment of chronic hepatitis. Aust. J. Med. Herbal. 6, 94–98 (1994)Google Scholar
  5. 5.
    A.H.K. Kundi, F.K. Wazir, G. Abdul, Z.D.K. Wazir, Physicochemical characteristics and organoleptic evaluation of different ber (Ziziphus jujuba Mill.) cultivar. Sarhad J. Agric. 5, 149–155 (1989)Google Scholar
  6. 6.
    S.H. Choi, J.B. Ahn, N. Kozukue, C.E. Levin, M. Friedman, Distribution of free amino acids, flavonoids, total phenolics, and antioxidative activities of jujube (Ziziphus jujuba) fruits and seeds harvested from plants grown in Korea. J. Agric. Food Chem. 59, 6594–6604 (2011)CrossRefGoogle Scholar
  7. 7.
    J.V. Possingham, Under-exploited wild species that have potential for Horticulture. Adv. Hortic. Sci. 4, 49–55 (1990)Google Scholar
  8. 8.
    T. Koyuncu, Y. Pinar, F. Lule, Convective drying characteristics of azarole red. J. Food Eng. 78, 1471–1475 (2007)CrossRefGoogle Scholar
  9. 9.
    S. Fang, Z. Wang, X. Hu, K. Ashim, Datta hot air drying of whole fruit Chinese jujube (Zizyphus jujuba Miller): thin-layer mathematical modelling. Int. J. Food Sci. Technol. 44, 1818–1824 (2009)CrossRefGoogle Scholar
  10. 10.
    A. Wojdyło, A. Figiel, K. Lech, C.A.A. Barrachina, P. Legua, F. Hernández, Chemical composition, antioxidant capacity, and sensory quality of dried jujube fruits as affected by cultivar and drying method. Food Chem. 201, 307–314 (2016)CrossRefGoogle Scholar
  11. 11.
    S.K. Giri, S. Prasad, Drying kinetics and rehydration characteristics of microwave-vacuum and convective hot-air dried mushrooms. J. Food Eng. 78, 512–521 (2007)CrossRefGoogle Scholar
  12. 12.
    Z. Jiancai, X. Zuobing, Characterization of the major odor-active compounds in dry jujube cultivars by application of gas chromatography—olfactometry and odor activity value. J. Agric. Food Chem. 66, 7722–7734 (2018)CrossRefGoogle Scholar
  13. 13.
    Z. Liuwei, L. Fengmao, G. Jing, M. Lili, W. Liming, X. Xiaofeng, Changes in eleven pesticide residues in jujube (Ziziphus jujuba Mill.) during drying processing. Drying Technol. 36, 965–972 (2018)CrossRefGoogle Scholar
  14. 14.
    P. Yunfeng, D. Tian, W. Wenjun, X. Yanju, Y. Xingqian, L. Mei, L. Donghong, Effect of harvest, drying and storage on thebitterness, moisture, sugars, free amino acidsand phenolic compounds of jujube fruit(Zizyphus jujuba cv. Junzao). J Sci Food Agric. 98, 628–634 (2018)CrossRefGoogle Scholar
  15. 15.
    B.D. Adiba, N. Mohamed, G. Antony, B. Salem, A. Karım, Evaluation of physical-chemical, pharmacodynamic and pharmacological attributes of hot air dried and swell dried jujube powders. J. Food Process Eng. 40, 1745–4530 (2017)Google Scholar
  16. 16.
    Q. Chen, J. Bi, X. Wu, J. Yi, L. Zhou, Drying kinetics and quality attributes of jujube (Zizyphus jujuba Miller) slices dried by hot-air and short- and medium-wave infrared radiation. Food Sci. Technol. 64, 759–766 (2015)Google Scholar
  17. 17.
    D. Engin, T. Yahya, Drying characteristics of garlic (Allium sativum L) slices in a convective hot air dryer. Heat Mass Transfer. 50, 779–786 (2014)CrossRefGoogle Scholar
  18. 18.
    G.V. Barbosa-Canovas, E. Ortega-Rivas, P. Juliano, H. Yan, Physical Properties, Processing, and Functionality (Kluwer Academic/Plenum Publishers, Food Powders, 2005) New YorkGoogle Scholar
  19. 19.
    R.L. Carr, Evaluating flow properties of solids. Chem. Eng. Sci. 72, 163–168 (1965)Google Scholar
  20. 20.
    N. Jinapong, M. Suphantharika, P. Jamnong, Production of instant soymilk powders by ultrafiltration, spray drying and fluidized bed agglomeration. J. Food Eng. 84, 194–205 (2008)CrossRefGoogle Scholar
  21. 21.
    P. Ruperez, G. Toledano, Celery by-products as a sourceof mannitol. Eur. Food Res. Technol. 216, 224–226 (2003)CrossRefGoogle Scholar
  22. 22.
    A. Vega-Gálvez, K. Ah-Hen, M. Chacana, J. Vergara, J. Martínez-Monzó, P. García-Segovia, R. Lemus-Mondaca, K.Di Scala, Effect of temperature and air velocity on drying kinetics, antioxidant capacity,total phenolic content, colour, texture and microstructure of apple (var. Granny Smith) slices. Food Chem. 132, 51–59 (2012)CrossRefGoogle Scholar
  23. 23.
    G.P. Sharma, S. Prasad, Drying of garlic (Allium sativum) cloves by microwave-hot air combination. J. Food Sci. 46, 410–413 (2001)Google Scholar
  24. 24.
    G. Dadalı, K.D. Apar, B. Ozbek, Estimation of effective moisture diffusivity of okra for microwave drying. Drying Technol. 25, 1445–1450 (2007)CrossRefGoogle Scholar
  25. 25.
    A. Motevali, A. Abbaszadeh, S. Minaei, M.H. Khoshtaghaza, B. Ghobadian, Effective moisture diffusivity, activation energy and energy consumption in thin-layer drying of jujube (Zizyphus jujube Mill). J. Agric. Food Technol. 14, 523–532 (2012)Google Scholar
  26. 26.
    S. Darıcı, S. Şen, Experimental investigation of convective drying kinetics of kiwi under different conditions. Heat Mass Transfer. 51, 1167–1176 (2015)CrossRefGoogle Scholar
  27. 27.
    I. Doymaz, Drying behaviour of green beans. J. Food Eng. 69, 161–165 (2005)CrossRefGoogle Scholar
  28. 28.
    P.S. Madamba, R.H. Driscoll, K.A. Buckle, The thin layer drying characteristics of garlic slices. J. Food Eng. 29, 75–97 (1996)CrossRefGoogle Scholar
  29. 29.
    S. Fang, Z. Wang, H. Xiaosong, K.D. Ashim, Hot-air drying of whole fruit Chinese jujube (Zizyphus jujuba Miller): physicochemical properties of dried products. Int. J. Food Sci. Technol. 44, 1415–1421 (2009)CrossRefGoogle Scholar
  30. 30.
    J.V. Link, G. Tribuzi, J.B. Laurindo, Improving quality of dried fruits: a comparison between conductive multi-flash and traditional drying methods. Food Sci. Technol. 84, 717–725 (2107)Google Scholar
  31. 31.
    M. Koç, B. Koç, M. Sakin-Yılmazer, F. Kaymak-Ertekin, G. Susyal, and N. Bağdatlıoğlu, Physicochemical characterization of whole egg powder microencapsulated by spray drying. Drying Technol. 29, 780–788 (2011)CrossRefGoogle Scholar
  32. 32.
    D.A. Botrel, S.V. Borges, R.V. Fernandes, A.D. Viana, J.M. Costa, G.R. Marques, Evaluation of spray drying conditions on properties of microencapsulated oregano essential oil. Int. Food Sci. Technol. 47, 2289–2296 (2011)CrossRefGoogle Scholar
  33. 33.
    Y.H. Roos, Thermal analysis, state transitions and food quality. J. Therm. Anal. Calorim. 71, 197–203 (2003)CrossRefGoogle Scholar
  34. 34.
    E.K. Katekawa, M.A. Silva, On the influence of glass transition on shrinkage in convective drying of fruits: a case study of banana drying. Drying Technol. 25, 1659–1666 (2007)CrossRefGoogle Scholar
  35. 35.
    Y. Deng, Y. Zhao, Effect of pulsed vacuum and ultrasound osmopretreatments on glass transition temperature, texture, microstructure and calcium penetration of dried apples (Fuji). Food Sci. Technol. 41, 1575–1585 (2008)Google Scholar
  36. 36.
    C. Contreras, M.E. Martín, N. Martínez-Navarrete, A. Chiralt, Effect of vacuum impregnation and microwave application on structural changes which occurred during air-drying of apple. Food Sci. Technol. 38, 471–477 (2005)Google Scholar
  37. 37.
    M.E. Dalmau., G.M. Bornhorst, V. Eim, C. Rosselló, S. Simal, Effects of freezing, freeze drying and convective drying on in vitro gastric digestion of apples. Food Chem. 215, 7–16 (2017)CrossRefGoogle Scholar
  38. 38.
    S. Hogekamp, H. Schubert, Rehydration of food powders. Food Sci. Technol. Int. 9, 223–235 (2003)CrossRefGoogle Scholar
  39. 39.
    R.S. Reddy, C.T. Ramachandraa, S. Hiregoudar, U. Nidoni, J. Ramb, M. Kammar, Influence of processing conditions on functional and reconstitution properties of milk powder made from Osmanabadi goat milk by spray drying. Small Rumin Res. 119, 130–137 (2014)CrossRefGoogle Scholar
  40. 40.
    M.I.M.J. Barbosa, C.D. Borsarelli, A.Z. Mercadante, Light stability of spray dried bixin encapsulated with different edible polysaccharide preparations. Food Res. Int. 38, 989–994 (2005)CrossRefGoogle Scholar
  41. 41.
    Y.H. Hui, C. Clary, M.M. Farid, O. Fasina, A. Noomhorm, J. Welti-Chanes, Food Drying Science and Technology: Microbiology, Chemistry, Applications (DEStech Publications, Inc., USA, 2008)Google Scholar
  42. 42.
    F. Vojdani, Solubility, in Methods of Testing Protein Functionality, ed. by M.G. Hal (Blackie Academic and Professional, London, 1996)Google Scholar
  43. 43.
    Y. Sakurai, R. Mise, S. Kimura, S. Noguchi, Y. Iwao, S. Itai, Novel method for improving the water dispersibility and flowability of fine green 4 tea powder using a fluidized bed granulator. J. Food Eng. 10, 1016 (2017)Google Scholar
  44. 44.
    T.A. Shittu, M.O. Lawal, Factors affecting instant properties of powdered cocoa beverage. Food Chem. 100, 91–98 (2007)CrossRefGoogle Scholar
  45. 45.
    M.D. Purkayastha, A. Nath, B.C. Deka, C.L. Mahanta, Thin layer drying of tomato slices. J. Food Sci. Technol. 50, 642–653 (2013)CrossRefGoogle Scholar
  46. 46.
    E. Rahman, A. Momin, L. Zhao, X. Guo, D. Xu, F. Zhou, B. Ji, Bioactive, nutritional composition, heavy metal and pesticide residue of four Chinese jujube cultivars. Food Sci Biotechnol. 27, 323–331 (2018)CrossRefGoogle Scholar
  47. 47.
    F. Yaşa, Türkiye’de yetiştirilen hünnap meyvesinin bileşimi ve meyvenin kurutulmasi sirasinda bileşiminde meydana gelen değişimler. Pamukkale Üniversitesi Fen Bilimleri Enstitüsü Gıda Mühendisliği Anabilimdalı (2016)Google Scholar
  48. 48.
    L. Jin-Wei, F. Liu-Ping, D. Shao-Dong, D. Xiao-Lin, Nutritional composition of five cultivars of Chinese jujube. Food Chem. 103, 454–460 (2007)CrossRefGoogle Scholar
  49. 49.
    K. Gornicki, A. Kaleta, Drying curve modelling of blanched carrot cubes under natural convection condition. J Food Eng. 82, 160–170 (2007)CrossRefGoogle Scholar
  50. 50.
    P. Yunfeng, D. Tian, W. Wenjun, X. Yanju, Y. Xingqian, L. Mei, L. Donghong, Effect of harvest, drying and storage on the bitterness, moisture, sugars, free amino acids and phenolic compounds of jujube fruit (Zizyphus jujuba cv. Junzao). J Sci Food Agric. 98, 628–634 (2018)CrossRefGoogle Scholar
  51. 51.
    K.B. Pandey, I.R. Syed, Plant polyphenols as dietary antioxidants in human health and disease. Oxid. Med. Cell Longev. 2, 270–278 (2009)CrossRefGoogle Scholar

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

Authors and Affiliations

  1. 1.Department of Food Engineering, Faculty of EngineeringAdnan Menderes UniversityAydınTurkey

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