The effect of different concentrations of three types of emulsifier on color of an industrial-made dark chocolate

Dark chocolate is a suspension of solid particles from sugar and cocoa dispersed in a fat continuous phase in a process assisted by emulsifiers, usually a combination of lecithin and polyglycerolpolyricinoleate. Some humectant materials such as glycerin are added to the chocolate ingredients. Brown color of chocolates, which is one of the most quality attributes, affected by chocolate formulation and processing. The aim of this study was to follow color changes on the surface of industrial-made dark chocolate under different concentration of three types of lecithin, polyglycerolpolyricinoleate (both on 0.25 –0.5 %) and glycerin (0.1 –0.25 %), and under two levels of cooling temperature (7and -18 °C). A Minolta colorimeter was used to determine color of samples and the parameters measured were L, a and b. Whiteness index was calculated by a formula using L, a and b values. The results showed that the emulsifiers had a strong interactions and a considerable effect on color indices. Based on the results the cooling temperature exerts a great effect on the color parameters.

Keywords:

chocolate , emulsifier , color