RHEOLOGICAL PROPERTIES OF DATE JUICE CONCENTRATE (DIBS) DURING EVAPORATION PROCESS | ||
| Misr Journal of Agricultural Engineering | ||
| Article 18, Volume 34, Issue 1, January 2017, Pages 317-330 PDF (771.09 K) | ||
| Document Type: Original Article | ||
| DOI: 10.21608/mjae.2017.97116 | ||
| Authors | ||
| Omnia E. Salama1; Manal A. Sorour1; M. M. Mostafa2; M. A. Elnono2 | ||
| 1Food Engineering and Packaging, Department, Food Technology Research Institute, Agricultural Research Center, Giza, Egypt. | ||
| 2Agriculture Engineering Department, Faculty of Agriculture, Ain Shams University., Egypt. | ||
| 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 | ||
| Rheological Properties; Date Juice Concentrate; Flow Behavior; Activation Energy | ||
| References | ||
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