DRYING FIGS USING DEVELOPMENT MECHANICAL DRYER

Helmy, M. A.; Sorour, H. M.; El-Kholy, M. M.; El-Mesery, H. S.

doi:10.21608/mjae.2010.105358

DRYING FIGS USING DEVELOPMENT MECHANICAL DRYER

Document Type : Original Article

Authors

¹ Professor of Agric.Eng., Agric. Eng. Dept., Fac. of Agric., Kaferelsheikh Univ., Egypt.

² Senior Researcher, Agric. Eng. Res. Institute, Agric.Res. Center, Dokki, Giza, Egypt.

³ Agric. Eng., Agric. Eng. Res. Institute, Agric. Res. Center, Dokki, Giza, Egypt.

10.21608/mjae.2010.105358

Abstract

The present work was conducted to study and simulate the drying behavior of whole figs fruits under different drying parameters. The approach led to develop a small scale industrial figs dryer using butane-gas as heat energy source and also describe the change in whole figs moisture content during actual drying process using the proposed dryer. The experimental were carried out using fresh whole figs “Ficus Carica” its local name is "Sultani". Whole figs fruits were treated before drying by treatment (A): the fruits sulfured by dipped in 1.5% aqueous sodium metabisulfit and, treatment (B): the fruits were dipped in 1% sodium hydroxide before treated with solution of 1.5% sodium metabisulfit. Four levels of drying air temperature (55, 65, 75 and 85 °C) and four levels drying air velocity (0.2, 0.4, 0.6 and 1 m/s)
The results showed that, the reduction rate of whole figs moisture content was increased with the increasing of drying air temperature and air velocity in all pretreatment of simple whole figs. On the other hand, the whole figs moisture content reduction rates on the treatment (B) were higher than that in treatment (A) for all the combination of the parameters. The recorded drying time for drying whole figs from an initial moisture content of about 223-400% d.b to a final moisture content of about 18-20% d.b were 35-20hours under different drying parameters. Heating control unit using butane-gas was used to control heat source in drying air temperature with fluctuation of about ±1.7 °C for all levels of drying air temperature. The total capacity of the dryer is about 40 kg of fresh figs producing about 10 kg of dried figs, the calculated operation cost of the dryer approaches about 6.3 LE/kg of dried whole figs fruits. The developed dryer of whole figs fruits showed good mechanical and thermal performance.

Main Subjects

Processing Engineering of Agricultural Products

References

Adams, R. L. and J.F. Thamposon (1985). Improving drying uniformity in concurrent flow tunnel dehydrators. Transaction of the ASAE, 28(3): 890-892.

Adl EL-Aal, F. E. A. (1998). Chemical and technological studies on some foods. Effect of some dehydration on the Chemical composition and quality of dried apricot Prune, fig and tomato. Ph. D. Thesis, Fac. of Agric, Tanta Univ., Egypt.

A.O.A.C. (1985). Official Methods of Analysis, association of official analytical chemists Washington, D.C. USA.

El-Sebaii A. A, S. Aboul-Enien, M. R. I, Ramadan, and H. G., El-Gohary, (2002). Parametric study of a solar air heater with and without thermal storage for solar drying applications. Renewable Energy;21:505–22.

Gabas, A. L., F. C. Mengalli and J. Telis, (1999). Effect of chemical pertreatment on the physical properties of dehydrated figs. Drying Technology, 17(6), 1215-1226.

Guine, R. P. F. (2008). Pear drying: Experimental validation of a mathematical prediction model. Food and bio products processing, 83(C4): 273–276.

Jindal, V. K. and V. G. Reyes, (1987).Conduction heating of rough rice accelerated drying. Paper no. 87-6043, American Society of Agricultural Engineers (ASAE) summer Meeting Baltimore, June 28-July 1, ASAE, St. Joseph, Mi.

Karathunos, V. T. and V.G. Belessiotis (1997). Sun and artificial air drying kinetics of some agricultural products. J. of Food Engineering, 3 1(1): 35-46.

Lewicki, P. P (1998). Some remarks on rehydration of drird foods. Journal of Food Process Engineering, 36, 81–87.

Pangavhane, D. R., R. L. Sawhnew, and P. N. Saravadia, (2000). Drying kinetic studies on single layer Thompson seedless grapes controlled heated air conditions. Journal of Food Processing and Preservation, 24, 335-352.

Stamatios, J., G. Babalis, V. Assilios, and K. Belessitis. (2005). Evaluation of thin layer drying models for describing drying kinetics of figs (Ficus carica). Journal of Food Engineering, 65 (3), 449-458.

Vinson, J. A. (1999). The functional food properties of figs. Cereal Foods World, 44(2), 82–87

Xanthopoulos, G., N. Oikonomou, and G. Lambrinos (2007). Applicability of a single-layer model to predict the drying rate of whole figs. Journal of Food Engineering, 81, 553-559.

المراجع العربیة:

مصطفى,م. م، ش. ش. رزق, م. ن. متولى (1992). استخدام الطاقة الشمسیة فى تجفیف المحاصیل الزراعیة. الدار الدولیة للنشر والتوزیع, القاهرة, مصر.