Rheological of chocolate-flavored, reduced-calories coating as a function of conching process

Abstract

Continuous flow and linear viscoelasticity rheology of chocolate coating is studied in this work using fat substitute gums (xanthan, GX). An alternative conching process, using a Rotor-Estator (RE) type impeller, is proposed. The objective is to obtain a chocolate coating material with improved flow properties. Characterization of the final material through particle size distribution (PSD), differential scanning calorimetry (DSC) and proximal analysis is reported. Particle size distribution of the final material showed less polydispersity and therefore, greater homogeneity; fusion points were also generated at around 20°C assuming crystal type I (β' 2 ) and II (α). Moreover, the final material exhibited crossover points (higher structure material), whereas the commercial brand chocolate used for comparison did not. The best conditions to produce the coating were maturing of 36 h and 35°C, showing crossover points around 76 Pa and a 0.505 solids particle dispersion (average particle diameter of 0.364 μm), and a fusion point at 20.04°C with a ΔH f of 1.40 (J/g). The results indicate that xanthan gum is a good substitute for cocoa butter and provides stability to the final product.

Physical characterization of chocolates prepared with various soybean and milk powders

“…Therefore, it was concluded that all samples were in Form V, the most convenient form, without being affected by fat content and PSD. Medina‐Torres, Sanchez‐Olivares, Nuñez‐Ramirez, Moreno, and Calderas (2014) found that T peak values did not change upon PSD in chocolate coatings. Another insignificant change was observed in T index values, representing the curve's width.…”