Simplex Lattice Mixture Design Approach for Optimization of Jaggery Granules and Finger Millet Flour-Based Functional Muffins

Abstract

The increasing focus on therapeutic nutrition has heightened consumer demand for health-promoting foods rich in antioxidants, fiber, and minerals. Consequently, food manufacturers are examining underutilized crops like millets for developing functional products. Cakes, widely consumed due to their convenience, variety, and affordability, are primarily made from wheat flour and feature a flexible, elastic crumb structure. This research aimed to create functional muffins with improved nutritional values using a combination of finger millet and whole wheat flour for nutrient enrichment and jaggery as a natural sweetener, employing a simplex lattice mixture design. The study assessed the composite flour's impact on various quality characteristics of the muffins, including volume, color, texture, minerals, antioxidant activity, and sensory properties. The interaction between the models for WWF and FMF significantly influenced firmness (571.50–1545.24 g) and L* (26.96–58.81) values for texture and color, respectively. Most nutrients showed similar results. Linear, quadratic, cubic, and quartic models for all responses were significant (p < 0.05), with adjusted R² ranging from 0.62 to 0.99. Based on maximum volume, minimal ∆E, and highest sensory score, the software identified 44.61% WWF and 55.38% FMF as the optimal blend, with a desirability of 0.772. This blend yielded protein, fiber, ash, calcium, and iron contents of 6.8%, 0.74%, 1.8%, 172.11 mg/100 g, and 2.25 mg/100 g, respectively. The scanning electron microscopy analysis revealed structural differences at the microscopic level between the control and optimized muffins. Additionally, FTIR analysis indicated the presence of O–H and C–H compounds in both the control and optimized muffin samples. The study concluded that jaggery can fully replace refined white sugar and that a blend of whole wheat flour and finger millet flour improves the technical and nutritional properties of muffins.