Effects of sugar replacers on physicochemical, rheological and sensory properties of milk chocolate

High sugar content is one of the major concerns in chocolate formulations. Although much research has been conducted aiming at replacing sugar with suitable replacres in milk chocolate, the results have not been very conclusive due to inducing undesirable texture and laxative effects. Therefore, in the present study we investigated the production of a low-energy milk chocolate with prebiotic properties using a Simplex Lattice Mixture Design. Inulin as a prebiotic compound, with polydextrose, maltodextrin and a synthetic sweetener (sucralose), were used as sugar replacers in chocolate-making. Fifteen formulations were prepared using various ratios of these ingredients, and their effects on physicochemical, mechanical, rheological and sensory properties were determined. In general, chocolates with high a level of sugar substitutes had a higher moisture content, viscosity and yield stress and a lower hardness than other samples and the controls. The lowest moisture content, viscosity and yield stress, as well as the highest hardness, were observed at the moderate levels of the ingredients. From among the 4 mathematical models used, Casson model showed the best fitting with our data and was employed for predicting rheological properties of the low-energy chocolates. The overall acceptance of the chocolate samples showed a direct relation with inulin and polydextrose and an inverse relation with maltodextrin. Based on the results of superimposed contour plots, the optimal values of inulin, polydextrose, and maltodextrin were 6.48–32.41% and 67.2–86.2%, 0–28.3% and 58.8–78.3%, and 0–30.6%, respectively. In addition, our data on fat reduction showed the possibility of fat reduction up to 5% and, consequently, a considerable energy cut (29%), in milk chocolates. Based on our findings, the Simlex Lattice Mixture Design is an appropriate method for finding optimal levels of inulin, polydextrose and maltodextrin in formulation of milk chocolate and producing a low energy–prebiotic milk chocolate very similar to ordinary chocolates.