Effects of citrus pomace on mechanical, sensory, phenolic, antioxidant, and gastrointestinal index properties of corn extrudates

Abstract

Ready-to-eat snacks are popular among consumers, but these largely carbohydrate-based snacks have high glycemic indexes that pose various health issues, such as increased risk of diabetes, heart disease, high blood pressure, etc. This work aimed to increase the healthfulness (fiber, phenolic content, antioxidant capacity) of corn based extrudates through the addition of citrus pomace as a sustainable dietary fiber source. Extrudates were prepared using twin screw extrusion with citrus pomace concentrations in the range of 0%–15%, incorporated into corn grits. Results show that inclusion of 15% citrus pomace increased fiber content by 58.33% and dietary fiber contents increased 2.12 times compared to corn extrudates used as control samples. Antioxidant activity (DPPH) and mineral (calcium) contents of 5% pomace-containing extrudates significantly increased between 9.36 and 14.32 times respectively compared to the control sample without any supplementation. However, the expansion ratio, porosity, oil binding, and absorption capacities decreased due to the fiber addition. The sensory attributes of extrudates up to 5% pomace addition were acceptable in sensory evaluation. In the range of 0%–5% citrus pomace addition, extrudates may be successfully used for sustainable consumption, food waste management, and nutritional security.