Demand for use of natural sweeteners and prebiotic compounds for manufacture of sugar-free chocolates
has dramatically increased over the past decennium. However, their applicability in product formulation
and how these will affect the flow (rheological) and physical quality characteristics still remains a big
challenge. This study investigated the rheological properties, melting behaviours and other physical
quality characteristics of sugar-free chocolates processed from inulin and polydextrose mixtures as
bulking agents sweetened with stevia and thaumatin extracts. Standard reference chocolate was
developed using sucrose and the effects of the inulin/polydextrose and stevia/thaumatin ingredients on
the rheological properties, melting profiles, colour and hardness of the derived products measured using
standard methods. Generally, the sugar-free chocolates showed similar flow (rheological) and melting
properties as compared to the reference chocolate. Sucrose replacement with the inulin/polydextrose
and stevia/thaumatin extracts resulted in significantly higher Casson viscosity. There were however no
significant differences in the melting behaviour and texture of the sugar-free chocolates and the reference.
Chocolates containing the sugar substitutes recorded lower onset temperatures and higher peak
widths than the reference sample. Inulin and polydextrose mixtures could be used for sugar-free
chocolate manufacture with satisfactory physicochemical properties when sweetened with stevia or
thaumatin extracts.