Effect of alternative preservatives on the microbial quality, lipid stability and sensory evaluation of boerewors

Boerewors is a South African fresh sausage preserved with 450 mg/kg sulphur dioxide (SO2). The preservative effects of rosemary (Ros; 260 mg/kg) and chitosan (Chi; 10 g/kg) were compared to SO2. Eight boerewors models were formulated. Microbial, colour, lipid and sensory characteristics were evaluated. Chi and Chi in combination with other preservatives had a significant effect on reducing total bacterial, coliform and Enterobacteriaceae counts, comparable to SO2. Chi, however, had a better effect on decreasing yeasts and mould counts than SO2. Chi showed good colour properties comparable to SO2. Ros showed comparable lipid stability to SO2 but better when compared to Chi. Ros had a better effect on the sensory taste when compared to Chi, but SO2 was still preferred. Reduced levels of 100 mg/kg SO2 showed good antimicrobial and colour effects in combination with Chi and in combination with Ros as antioxidant and improving the sensory properties. Alternative preservatives can be used to reduce the SO2 content of boerewors.

► Chi significantly reduced total bacterial, coliform and Enterobacteriaceae counts. ► Chi showed good colour properties comparable to SO2. ► Ros had a better effect on the sensory taste when compared to Chi, but SO2 was still preferred. ► Reduced SO2 + Chi showed good antimicrobial and colour effects. ► Reduced SO2 + Ros showed good antioxidant characteristics and sensory properties.