Rheological Properties of Chocolate Pistachio

Journal of Nuts

مقاله 3، دوره 05، شماره 01، آذر 2014، صفحه 21-32   

شناسه دیجیتال (DOI): 10.22034/jon.2014.515694

نویسندگان

S. Khorasani^{* 1}؛ M. H. Azizi²؛ M. Eshaghi³

¹Department of Food Science & Technology, Tarbiat Modarres University, Tehran, Iran

²Department of Food Science and Technology, Tarbiat Modares University, Tehran, Iran

³Department of Food Science and Technology, Halva Oghab Company, Tehran, Iran

چکیده

This research aimed to assess and determine rheological properties of chocolate pistachio produced from various volumes of monoglycoside (1% and 2%), date powders (34, 38 and 42%) and pistachio pastes. The analyses were performed at temperaturesof 45 ºC, 65 ºC after 3 and 5 hours of processing. These products were found to exhibit nonNewtonian, pseudo-plastic behavior at all treatments. Apparent viscosities versus speed data were successfully fitted to a power law model. The flow behavior index, n, varied in the range of 0.8-0.94. The consistency index, k, was in the range 101.495-167.738 pa - s n . According to statistical analysis, the exponential model was a better model to describe the effect of the soluble solids on the viscosity of chocolate pistachio containing varying percentages of date powder. The activation energy (Ea) was 446.2-41330 j/mol.

کلیدواژه‌ها

Chocolate pistachio؛ Non-Newtonian؛ Pistachio paste؛ power law؛ Pseudo plastic behavior