Chocolate is a product obtained by grinding roasted cocoa beans and contains approximately equal quantities of fat and solid material very finely dispersed in the fat phase.
Lecithin is one of the most effective natural dispersing agents and it has been used in all chocolate productions for many years. The addition of lecithin during the “finishing” step of chocolate production allows the adjustment of the two main rheological parameters, viscosity and yield value. The same effect can be obtained by using cocoa butter, but due to the high cost of this component it is very important to employ the proper quality and quantity of lecithin.
Optimum viscosity and yield value:
The reduction of the surface tension of the fat and the decrease of the energy between the different solid particles of the chocolate improve the flow properties of the mass. The diagram shows the behaviour of the viscosity and yield value according to the lecithin concentration, achieving optimal values of these parameters by using between 0.3-0.5% of lecithin. An overdose increases the yield value again; therefore the dosage must be adjusted to the convenient level depending on the chocolate composition.
In addition, the ratio of the phospholipids in lecithin is very important. Phosphatidylcholine is the responsible of the viscosity decrease whereas phosphatidylethanolamine bring about the lowest yield value.
In our range of products VEROLEC NON GMO IP for chocolate applications, the balance of both phospholipids has been adjusted in order to achieve the best performance and to ensure uniform quality. In chocolate coatings the regulation of viscosity and yield value is of great importance to regulate the layer thickness of chocolate in the end product.
Reduce Fat Bloom:
Concerning the fat bloom phenomena, it is well known that the more fine and stable dispersion the less fat bloom occurrence. Lecithin, clearly responsible for this stability, also improves the surface appearance of the piece and gives an optimal consistency and texture, without streaks on the fracture surface.