EFFECT OF DIFFERENT DRYING METHODS ON SOME PROPERTIES OF DRIED OKRA

Document Type : Original Article

Authors

1 Lect. of Ag. Eng., Ag. Eng. Dept., Fac. of Ag., Menoufia Univ., Egypt.

2 Assoc. Prof. of Ag. Eng., Ag. Eng. Dept., Fac. of Ag., Menoufia Univ., Egypt.

3 Postgraduate 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

Main Subjects

References

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