Formulation, Optimization, and Quality Evaluation of Value-Added Finger Millet–Jaggery Chocolate

Abstract

The present study was undertaken to develop and optimize a jaggery-based chocolate enriched with sprouted finger millet flour and to assess its nutritional and textural characteristics. Response surface methodology (RSM) was applied using Design-Expert software (ver. 11.1.0.1). The independent variables selected were cocoa butter replacement with coconut oil (20–30% w/w), conching time (120–180 min), and sprouted finger millet flour incorporation (20–40% w/w). A total of seventeen experiments were performed, and the responses were modelled through multiple regression analysis. The optimized formulation, exhibiting maximum overall desirability, comprised of 22% (w/w) cocoa butter replacement with coconut oil, 150 min of conching, and a 39% (w/w) incorporation of sprouted finger millet flour. The optimized product contained 5.16% moisture, 2.66% ash, 23.60% crude fat, and 9.87% crude protein. Textural analysis revealed hardness of 305.6 N, adhesiveness of 2.14 N·s, cohesiveness of 0.101, and chewiness of 4.07 N. Sensory evaluation indicated high acceptability, with mouthfeel and overall acceptability scores of 8.12 and 7.80, respectively. Model validation demonstrated no significant differences between predicted and experimental values, confirming the adequacy and reliability of the developed models.