Phytonutrient Content, Antioxidant Potential and Acceptability of Muffins Functionalized with Soy and Citrus Industry Waste

The study aimed to effectively utilize soy (okara) and citrus juice (citrus peel) industry waste for developing functionalized bakery product. Muffins were prepared using composite flours having okara along with candied citrus peel. Flours were evaluated for the change in techno-functional properties with increasing level of okara addition. Muffins were analyzed for their physical, chemical, functional and sensory characteristics. Muffins with 15% okara with 2% candied citrus peel were found to be highly acceptable with improved protein (12.70%), dietary fiber (8.26%), total mineral (1.86%), phenols (88.12 mg 100g(-1)) and flavonoid content (96.31 mu mole Trolox 100g(-1)) with insignificant changes in mouthfeel and total calorific value. Majorly, citrus peel contributed to the antioxidants (phenols and flavonoids) of functionalized muffins. Okara addition resulted in similar to 22% increase in protein and similar to 45% increase in dietary fiber content of the muffins. Performance of polypropylene was superior over cling film in terms of muffin quality during 9days ambient storage. Functionalized muffins, high in protein, dietary fiber, total ash and antioxidants, can be developed by effective utilization of waste from soy (okara) and citrus juice industry (citrus peel). The naturally colored candied peel can serve as an alternate to the synthetically colored tutti fruitti that is added to the baked products to improve their appearance and taste. Almost similar baking losses and raw material input cost associated with the optimized product shows its possible adoption by any bakery industry.