Abstract
Pekmez is a concentrated and shelf life extended form of grape juice. We investigated the material behavior and the effect of processing factors during its solidification using in situ rheometry and color measurement by computer vision. Rheologically, pekmez (45.3 to 75 °Brix) is a Newtonian product. As expected, its viscosity increased with increasing solid content and decreasing temperature. A simplified model was proposed to describe the combined effect of concentration and temperature on pekmez viscosity. The color of pekmez changed from dark brown to white depending on the processing conditions such as the type and amount of whitener added and the rate and duration of mixing.
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Kaya, A., Ko, S. & Gunasekaran, S. Viscosity and Color Change During In Situ Solidification of Grape Pekmez. Food Bioprocess Technol 4, 241–246 (2011). https://doi.org/10.1007/s11947-008-0169-4
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DOI: https://doi.org/10.1007/s11947-008-0169-4