Impact of Limonene on the Physical Properties of Reduced Fat Chocolate

Abstract

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.

The Effect of Limonene on the Crystallization of Cocoa Butter

“…The crystallization of cocoa butter in the presence of limonene occurred at a lower temperature and the crystallization enthalpy is lower. This indicates that limonene affects crystallization to lower forms as previously observed by Do et al [20].…”

“…The research reported here is an attempt to answer questions raised during previous work on the use of limonene in chocolate [20]. The original work was motivated by the observation that the addition of limonene to molten chocolate in quantities of up to 5% by total weight lead to a decrease in the hardness of chocolate and also significantly decreased the viscosity of the melt, thereby facilitating the production of reduced fat chocolates [21].…”

“…Chocolates containing limonene were found to have an orange flavor [21]. In order to understand the effect of limonene in decreasing the viscosity and hardness of chocolates Do et al [20] investigated physical properties such as viscosity, density, solid fat content (SFC) and the melting profile of chocolate samples containing limonene and control samples without limonene. They demonstrated that limonene mixed readily with cocoa butter triglycerides, diluting the fat and leading to a decrease in the overall fat viscosity.…”

Specialty oils and fats in confectionery

“…Do et al (2008) found that adding limonene to chocolate considerably reduced its viscosity, thus opening the door to the possibility of more easily producing a low-fat chocolate. These are oils that will give some form of flavor either to chocolate or to a filling, and the use of mint oil, orange oil, and lemon oil is quite common.…”

Rheology of food materials

“…Rheological characterization of the flow properties as well as modifications of the ingredients are required to optimize the chocolate suspension. In the first case, the particle size distribution and the particle shape can be adapted to keep the chocolate melt viscosity acceptable for processing [33,[50][51][52][53] while for the later case addition of biopolymer gels or oils has been proposed [23,54]. In both cases, rheological investigations support the optimization the final food product by helping to understand the role of other relevant ingredients, i.e.…”