Optimal‐formulas a, and b including 12%, 8% eggplant‐fiber replacement with wheat flour, 71%, 57% whole‐egg, and 70%, 70% sugar (based on wheat flour + eggplant‐fiber weight), respectively, were designed using RSM. According to the results, the optimal‐formulas, due to the presence of eggplant‐fiber, contain fewer calories, more moisture, ash, antioxidant activity, and fiber content than the control. The optimal‐formulas a and b in terms of color (a*, b*, L*, and Chroma indices) were significantly different from the control and the control had a brighter color due to the increased sugar content. In the optimal‐formulas, color changes gave more intense colors than the control. As for textural properties, after 10 days, the optimal‐formulas were similar to each other; however, they were significantly different from the control (except in the springiness factor). Overall, the optimal‐formula b had greater similarities (such as porosity) to the control.
Practical applications
Response surface methodology suggested two optimal‐formulas A and B. The optimal‐formulas A & B including 12% & 8% replacing eggplant‐fiber with wheat flour, 71% & 57% whole‐egg, and 70% & 70% sugar (based on wheat flour + eggplant‐fiber weight), respectively. Eggplant decreased the cupcake calories, whereas increased the cupcake fiber, ash, and antioxidant activity, consequently nutritional values. In terms of the textural properties except for springiness, after 10 days, the optimal‐formulas were similar to each other; however, they were significantly different from the control.