Rheological characterization of tahin/pekmez (sesame paste/concentrated grape juice) blends

Date

2005-07-01

Author

Arslan, E
Yener, Meryem Esra
Esin, A

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Rheological properties of tahin/pekmez blends were determined at different tahin concentrations (20-32%) and temperatures (35-65 degrees C) by using a concentric cylinder rotational viscometer. Tahin/pekmez blends were found to exhibit non-Newtonian, shear thinning behavior at all temperatures and tahin concentrations. Apparent viscosity versus shear rate data was successfully fitted to the power-law model. The flow behavior index, n varied in the range of 0.7-0.85. The consistency coefficient, K, was in the range of 282-2547 mPa s(n). Both parameters were significantly affected by temperature. The effect of temperature on n did not follow a descriptive trend while the relation between temperature and K was described by an Arrhenius-type equation. Activation energies appeared in the range of 13376-28592J/mol with increasing concentration. The effect of concentration was significant for only K and it was described by exponential and power functions. A mathematical expression to relate apparent viscosity to temperature, tahin concentration and shear rate was proposed.

Subject Keywords

Rheology, Tahin (Sesame Paste), Pekmez (Concentrated Grape Juice), Blend

URI

https://hdl.handle.net/11511/47881

Journal

JOURNAL OF FOOD ENGINEERING

DOI

https://doi.org/10.1016/j.foodeng.2004.08.010

Collections

Department of Food Engineering, Article

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Citation Formats

E. Arslan, M. E. Yener, and A. Esin, “Rheological characterization of tahin/pekmez (sesame paste/concentrated grape juice) blends,” JOURNAL OF FOOD ENGINEERING, pp. 167–172, 2005, Accessed: 00, 2020. [Online]. Available: https://hdl.handle.net/11511/47881.