RHEOLOGICAL PROPERTIES OF DATE JUICE CONCENTRATE (DIBS) DURING EVAPORATION PROCESS

Salama, Omnia E.; Sorour, Manal A.; Mostafa, M. M.; Elnono, M. A.

doi:10.21608/mjae.2017.97116

RHEOLOGICAL PROPERTIES OF DATE JUICE CONCENTRATE (DIBS) DURING EVAPORATION PROCESS

Document Type : Original Article

Authors

¹ Food Engineering and Packaging, Department, Food Technology Research Institute, Agricultural Research Center, Giza, Egypt.

² Agriculture Engineering Department, Faculty of Agriculture, Ain Shams University., Egypt.

10.21608/mjae.2017.97116

Abstract

Date concentrate was obtained under vacuum using rotary evaporator by heating the date extract (19%) until it reaches (70%). Samples were collected during process until the end of process The rheological properties of Date juice concentrate were studied using Brookfield Rheometer (DV III ultra) at different temperatures (30, 40, 50 and 60°C),concentrations (30, 40, 50 and 60%) and shear rates (9.3– 93 s^-1). Shear rate - shear stress data indicated that all samples exhibited non-Newtonian pseudoplastic behavior.Dependence of apparent viscosity on temperature was related through the Arrhenius law. Effect of concentration on apparent viscosity was also studied and fitted well to power law.

Keywords

Main Subjects

Processing Engineering of Agricultural Products

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