Impact of Limonene on the Physical Properties of Reduced Fat Chocolate

The addition of limonene, a low molecular weight hydrophobic compound, to chocolate was reported to decrease the hardness and the viscosity of chocolate, facilitating the production and improving the eating quality of reduced fat chocolate. The objective of this study is to understand the functionality of limonene in decreasing the viscosity and the hardness of chocolate, a fat (cocoa butter)-based particulate suspension. This study shows that chocolate hardness was decreased because limonene mixes with cocoa butter, affects its crystallization pattern and decreases its solid fat content. After checking that limonene does not significantly affect the continuous phase volume fraction, we show that limonene decreases chocolate viscosity by decreasing the viscosity of the continuous phase, cocoa butter. The addition of low quantities of limonene in cocoa butter leads to a great decrease in the liquid fat viscosity. The dependence of the viscosity on the ratio of cocoa butter to limonene analyzed using Kay's equation seems to indicate that limonene mixes with and within the cocoa butter triglycerides, diluting the fat and leading to a decrease in the overall fat viscosity.