Formulation, nutritional profiling, and sensory evaluation of millet-based snack bars enriched with Gambian ingredients

Malnutrition continues to pose a significant public health concern in The Gambia (1) , where dietary diversity remains limited and nutrient-dense indigenous crops such as millet (2) , baobab (3) , mango (4) , and hibiscus (5) are underutilised. This study investigated the feasibility of developing millet-based functional snack bars incorporating Gambian ingredients to address dietary gaps, reduce food waste, and strengthen sustainable food systems. The objectives were to: (1) examine snacking behaviours and motivations among Gambian adults; (2) formulate and nutritionally analyse four millet-based snack bar variants; (3) assess their sensory acceptability among UK-based adults; and (4) explore Gambian consumers’ perceptions of front-of-pack (FoP) nutrition labelling. It was hypothesised that incorporating Gambian ingredients into snack bars would enhance nutritional value while maintaining sensory qualities, and that culturally adapted FoP labelling could improve consumer acceptability. A four-phase mixed-methods design was employed: (1) an online Snacking Behaviour Survey (SBS) among Gambian adults (n: 21); (2) formulation and nutritional analysis of four snack bar variants - Control (V1: millet, nuts, seeds, dried fruit), Functional (V2: millet + baobab, mango, hibiscus), Reduced-fat (V3), and Reduced-sugar (V4); (3) sensory evaluation among UK-based adults (n: 40); and (4) an online Nutrition Label Survey (NLS) with Gambian consumers (n:11). Quantitative data were analysed using descriptive statistics and non-parametric Friedman and Wilcoxon tests with significance set at p < 0.05. SBS results indicated high consumer interest in healthier snacks, with 90.5% expressing interest and 76.1% prioritising healthfulness in snack choices. Snacking behaviour was influenced by convenience, affordability, and cultural familiarity. Nutritional analysis confirmed that V3 achieved a 46% fat reduction and V4 achieved a 46% sugar reduction as compared to V1, surpassing the 30% reduction threshold required for UK/EU “reduced” nutrition claims. Sensory evaluation revealed statistically significant differences (p < 0.001) in taste, sweetness, and satisfaction across variants. Mean taste scores (five-point scale) were highest for V1 (4.2 ± 0.5), moderate for V2 (3.5 ± 0.5) and V3 (3.4 ± 0.6), and lowest for V4 (2.1 ± 0.6). Despite its favourable nutrient profile, V4 was least preferred, highlighting the sensory challenges of sugar reduction. NLS data indicated strong interest in nutrition information but limited comprehension of FoP traffic-light coding. Consumer acceptability was primarily driven by taste, texture, and ingredient familiarity rather than label interpretation. Millet-based snack bars incorporating Gambian crops demonstrate potential to enhance dietary diversity, utilise indigenous ingredients, and promote sustainable food innovation. Modest reformulation with functional ingredients (V2) improved nutritional value without compromising sensory appeal, while fat reduction (V3) proved more feasible than sugar reduction (V4). Culturally adapted labelling and consumer education are essential to maximise public health impact (6) . The findings support the United Nations Sustainable Development Goals 2 and 3 by promoting climate-resilient crops and reducing free sugar consumption within sustainable nutrition systems.