Spouted Bed Drying Characteristics of Rosehip

Abstract

Drying kinetics, effective moisture diffusivity and activation energy of rosehip (Rosa Canina L.) dried in a spouted bed dryer were investigated. The effects of the spouted bed drying and the inlet air temperature in the range of 40-80°C on the moisture ratio degradation and the drying rate of rosehip (Rosa Canina L.) were studied experimentally. Drying took place in the falling rate period. Drying time was reduced by 83% using a temperature of 80°C instead of 40°C. The effective moisture diffusivities of rosehip under spouted bed drying ranged from 2.5x10-10 to 2.56 x10-9 m2/s. The values of diffusivities increased with the increase in inlet air temperature. An Arrhenius relation with an activation energy value of 51.6 kJ/mol expressed the effect of temperature on the diffusivity.

Keywords

• Spouted bed drying; rosehip; drying kinetics; effective moisture diffusivity; activation energy.

References

1. Koyuncu, T., Tosun, I. & Ustun, N. S. (2003). Drying Kinetics and Color Retention of Dehydrated Rosehips. Drying technology, 21(7), 1369–1381 Erenturk, S., Gulaboglu, M. S. & Gultekin, S. (2005). The effects of cutting and drying medium on the vitamin C content of rosehip during drying. Journal of Food Engineering, 68, 513–518. Mathur, K.B. & Epstein, N. (1974). Spouted Beds. Academic Press, New York. Geldart, D. (1986). Gas fluidization technology. Wiley, New York. Evin . Gul H. & Tanyıldızı V. 008 . Grain drying in a paraboloid-based spouted bed with and without draft tube. Drying Technology, 26, 1577–1583. Crank, J. The mathematics of diffusion. Oxford, UK: Oxford University press (1975). Babalis S.J., Belessiotis V.G., Influence of the drying conditions on the drying constants and moisture diffusivity during the thin-layer drying of figs. Journal of Food Engineering 65 (2004) 449–458 Togrul, H. Suitable drying model for infrared drying of carrot. Journal of Food Engineering 77 (2006) 610–619 Henderson, S.M. (1974). Progress in developing the thin layer drying equation. Trans. ASAE. 17:1167-1172. Erbay Z., Icier F. (2010). A Review of Thin Layer Drying of Foods: Theory, Modeling, and Experimental Results. Critical Reviews in Food Science and Nutrition, 50:441–464. Kaleemullah, S., Kailappan, R. (2006). Modelling of thin layer drying kinetics of red chillies. Journal of Food Engineering. 76:531-537. Senadeera, W., Bhandari, B.R., Young, G., Wijesinghe, B. (2003). Influence of shapes of selected vegetable materials on drying kinetics during fluidized bed drying. Journal of Food Engineering. 58, 277-283. Doymaz, I. (2005). Drying behavior of green beans. Journal of Food Engineering. 69:161-165. Doymaz, I. (2004). Convective air drying characteristics of thin layer carrots. Journal of Food Engineering. 61:359-364. Kashaninejad, M., Mortazavi, A., Safekordi, A., Tabil, L.G. (2007). Thin-layer drying characteristics and modeling of pistachio nuts. Journal of Food Engineering. 78:98-108. Park, K.J., Vohnikova, Z., Brod, F.P.R. (2002). Evaluation of drying parameters and desorption isotherms of garden mint leaves (Mentha crispa L.). Journal of Food Engineering. 51:193-199. Madamba, P.S. (2003). Thin layer drying models for osmotically pre-dried young coconut. Drying Technology, 21:1759-1780.