Stability and dynamic rheological characterization of spread developed based on pistachio oil

Abstract

This study investigated the influence of formulation variables (pistachio oil (PO, 7.5 and 15%, w/w), Cocoa butter (CB, 7.5 and 15%, w/w), xanthan gum (XG, 0 and 0.3%, w/w), and distillated monoglyceride (DMG, 0.5 and 1%, w/w)) on the rheological properties and emulsion stability of spreads. Power law and Herschel–Bulkley models were used for modeling shear-thinning behavior of samples. The power law model was found to describe the flow behavior of spreads better than Herschel–Bulkley model. All the rheological properties were increased by adding XG to the spreads whereas increasing PO content caused to decrease them. The DMG had positive effect on apparent viscosity and elastic behavior but had negative effect on viscose behavior. Apparent viscosity was increased by adding CB while rheological modules were not significantly (p<0.05) affected. The XG and DMG improved stability of emulsion. The best spread formulation with optimum rheological properties was 15% PO, 7.5% CB, 0.3% XG and 1% DMG.