EFFECT OF DIFFERENT DRYING METHODS ON SOME PROPERTIES OF DRIED OKRA | ||||
| Misr Journal of Agricultural Engineering | ||||
| Article 36, Volume 34, Issue 4, October 2017, Page 2163-2180 PDF (1019.24 K) | ||||
| Document Type: Original Article | ||||
| DOI: 10.21608/mjae.2017.96538 | ||||
 View on SCiNiTO | ||||
| Authors | ||||
| M. H Keshek1; A. T. Taha2; M. M. Sobhy3 | ||||
| 1Lect. of Ag. Eng., Ag. Eng. Dept., Fac. of Ag., Menoufia Univ., Egypt. | ||||
| 2Assoc. Prof. of Ag. Eng., Ag. Eng. Dept., Fac. of Ag., Menoufia Univ., Egypt. | ||||
| 3Postgraduate student of Ag. Eng., Ag. Eng. Dept., Fac. of Ag., Menoufia Univ., Egypt. | ||||
| Abstract | ||||
| The aim of this work is to study the effect of drying air temperature in oven dryer and solar drying systems on the physical and mechanical properties of okra pods. Experiments were conducted at 40, 50, 60, 70 and 80 oC for oven dryer, meanwhile, solar drying systems were conducted at direct dryer with solar collector (D.C), direct dryer without solar collector (D), indirect solar dryer (IN.D) and glass cabinet dryer (G). The drying characteristics and the quality aspects of the dried okra pods were study. Results indicated that: -The lower drying time was 12 hours, by oven dryer at 80 oC for the treated okra pods. -The lower total color changes (∆E) for okra pods were 7.5 and 8.5 under the indirect solar dryer and oven dryer, respectively. -The higher total color changes (∆E) of okra pods were 33.4 and 31.2 under the indirect solar dryer at treated okra pods, and oven dryer at 80 oC, respectively. -The lower Firmness was 2.67 kg/cm2, when using the oven dryer at 40 oC untreated okra pods. The highest Firmness were 5.94 kg/cm2, for the treated okra pods. | ||||
| Keywords | ||||
| Okra; Color; Firmness; Solar; Drying | ||||
| References | ||||
|
Akpinar, E. K., Bicer, Y., & Yildiz, C. (2003). Thin layer drying of red pepper. Journal of Food Engineering, 59(1), 99–104.
Awady, M.N.; S.A. Mohamed; A.S. El-Sayed. and A.A. Hassanain (1993) "Utilization of solar energy for drying processes of agricultural products". Misr, J. Ag. Eng., 10(4):794-804.
Barrett, D. M., Beaulieu, J. C., & Shewfelt, R. (2010). Color, flavor, texture, and nutritional quality of fresh-cut fruits and vegetables: desirable levels, instrumental and sensory measurement, and the effects of processing. Critical Reviews in Food Science and Nutrition, 50(5), 369–389.
Bonazzi, C. and Dumoulin, E. (2011). Quality Changes in Food Materials as Influenced by Drying Processes . In: Drying Technology Volume 3: Product Quality and Formulation, First Edition (Edited by Tsotsas, E., Arun, S. and Mujumdar, A.S). Wiley-VCH Verlag GmbH & Co. KGaA. Published. pp. 1-20.
Boyer, J., & Liu, R. H. (2004). Review: Apple phytochemicals and their health benefits. Nutrition Journal, 3, 1–15.
Deell, J.R., Khanizadeh, S., Saad, F., Ferree, D.C. (2001). Factors affecting apple fruit firmness: a review. J. Am. Pomol. Soc. 55, 8–27.
Doymaz, I., & Pala, M. (2003). The thin-layer drying characteristics of corn. Journal of Food Engineering, 60, 125–130.
Fellows, J. P. 2000: Food Processing Technology: Cambridge: Wood head Publishing Limited.
Guerra, M. P., Kudo, T., Kon, T. and Holderbaum, D. F. (2010). Enzymatic browning, polyphenol oxidase activity and polyphenols in four apple cultivars: dynamics during fruit development. Hortscience 45(8): 1150 - 1154.
Gupta, P., Ahmed, J., Shivhare, U. S. and Raghavan, G. S. V (2002). Drying characteristics of red chilli. Drying Technology 20(10): 1975 - 1987.
Hossain, M. A. and Bala, B. K. (2002). Thin Layer Drying Characteristics for Green Chilli. Drying Technology 20 (2): 489 - 505.
Kim, K. B., Kim, M. S., Lee, S., Cho, B.K. (2009). Determination of apple firmness by nondestructive ultrasonic measurement. Postharvest Biology and Technology 52: 44–48.
Lee, K. W., Kim, Y. J., Kim, D. O., Lee, H. J., & Lee, C. Y. (2003). Major phenolics in apple and their contribution to the total antioxidant capacity. Journal of Agricultural and Food Chemistry, 51, 6516–6520.
Maskan, A., Kaya S., and Maskan, M. (2002). Hot air and sun drying of grape leather (pestil). Journal of Food Engineering 54: 81 - 88.
Mohamed, M. A.; G. R. Gamea; and M. H. Keshek (2010) "Drying characteristics of okra by different solar dryers". Misr J. Ag. Eng. Vol. 27( 1) :294 – 312.
Mongi, R.J. (2013): Solar drying of fruits and vegetables: dryers’ thermal performance quality and shelf life of dried mango, banana, pineapple and tomato, Ph.D. Thesis., sokoine university of agriculture. Morogoro, Tanzania.
Pék, Z., Helyes, L., & Lugasi, A. (2010). Color changes and antioxidant content of vine and postharvest-ripened tomato fruits. HortScience, 45(3), 466–468.
Perera, C. O. (2005). Selected quality attributed of dried foods. Journal of Drying Technology 23(4): 717 - 730.
Sahin, S., & Sumnu, S. G. (2006). Physical properties of foods. New York: Springer.
Sinha NK: (2006). Hand book of fruits and fruit processing. USA: Blackwell Publishing; 2006. p. 265–78.
Travers, S., (2013): Dry matter and fruit quality manipulation in the field and evaluation with nir spectroscopy, Ph.D. Thesis., Dept. of Food Science, Faculty of Science and Technology, Aarhus University, Denmark.
UNIDO. (2001a). Quality of dried foods and deteriorative reactions during drying [http://www.unido.org/fileadmin/import/32142_31QualityofDriedFoods.14.pdf].
Velic D, Planinic M, Tomas S, Bilic M (2004). Influence of airflow velocity on kinetics of convection apple drying. Journal of Food Engineering, 64:97–102.
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 Research International 40 (1), 39–46.
Yaldiz O; Ertekin C (2001). Thin layer solar drying of some vegetables. Drying Technology, 19, 583–596. | ||||
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