SAXS and SANS measurements on chocolate surfactants in triglyceride oils

Molten chocolate is a dense suspension of solids (mainly sugar) in oil, to which surfactants have been added to improve the flow properties, either during manufacture or in the consumers mouth ('mouth feel'). The two surfactants are lecithin, which is a lipid molecule derived from soya or egg, and a polymeric surfactant (PGPR) with a comb-like structure, the tynes of which resemble polymerised versions of the lecithin tails, and the backbone of which resembles a polymerised version of the lecithin head group. Used in combination these surfactants make it much easier for the suspension to flow. We have a model that explains this in terms of lamellar layers of lecithin incorporating PGPR at the sugar oil interface. To complete the model of how these form, we will perform small angle scattering of the surfactants individually and combined in the oils used to form our model molten chocolate.