Effect of transesterified amaranth oil oleogel as a cocoa butter replacer on the physicochemical properties of dark chocolate

Abstract

In this study the possibility of replacing cocoa butter with transesterified amaranth oil oleogel (EAO; CBR 100 and CBR 40 at the concentration of 5, 10, and 15 % (w/w)) was evaluated. For this goal, the triacylglycerol composition of amaranth oil, cocoa butter and 2 type of replacer (monoglyceride (MG) oleogel with amaranth oil, and the combination of 40 % this oleogel with 60 % EAO) were determined. The pure oleogel (amaranth oil mixed with 10 % MG) was named cocoa butter replacer 100 (CBR 100) and 40 % of this pure oleogel mixed with 60 % enzymatically transesterified amaranth oil was named cocoa butter replacer 40 (CBR 40). Then the chocolate samples were prepared. The physicochemical properties of chocolates were measured using color and fat bloom tests, differential scanning calorimetric (DSC), X-ray diffraction and texture. Results showed that enzymatic transesterification can significantly reduce the amount of dominant triacylglycerols of cocoa butter in amaranth oil. The control cocoa butter chocolate showed higher whiteness index and the highest level of fat bloom. DSC showed that the thermal parameters were similar for the most chocolate samples, except replacer with 15 % of oleogel. The control chocolate and 5 % concentration of oleogel and EAO mixture, had more β’ crystals, while chocolates containing replacers CBR 40/100 had more β type crystals, although hardness evaluation test showed no significant differences among the various types of chocolates. Accordingly, we consider the MG oleogel and its combination with EAO, especially in 5 % condensation, have potential as replacer for cocoa butter with no negative effect.