Optimisation of natural sweeteners for sugar reduction in chocolate flavoured milk and their impact on sensory attributes

Abstract Public Health bodies like the World Health Organization and Public Health England have identified addition of sugar to processed foods and beverages as a health concern. Owing to the increasing consumption of sugar sweetened chocolate flavoured milk in Australia among all age groups, this study was conducted to investigate the possibility of achieving a 50% of added sugar reduction in chocolate milk using natural non-nutritive sweeteners, namely stevia and monk fruit extract. Optimization of the sweeteners was successfully performed by Response Surface Methodology. Variables for 50% reduction of added sugar in chocolate milk were chosen as stevia sweetener (5-100 ppm) and monk fruit extract (50-100 ppm) based on preliminary trials. Sensory attributes (overall liking, appearance, aroma, sweetness, mouthfeel and aftertaste) were taken as the responses. The process was optimized with a combination of 56.27 ppm of stevia sweetener and 81.90 ppm of monk fruit extract with sensory attributes of 6.78, 6.47, 6.31, 6.47, 6.45 and 6.33, respectively for overall liking, appearance, aroma, sweetness, mouthfeel and aftertaste. Use of the two selected sweeteners in combination resulted in sweetness synergy. In addition, the bitter and metallic aftertastes of stevia were masked by the monk fruit extract and helped enhance the overall sensory attributes of the product compared to the control. This study provides insightful information for optimizing sweeteners for sugar reduction in milk-based product.