UV-C treatment as a valorization strategy for apple by-product: Enhancement of dietary fiber, polyphenols, and antioxidant capacity

The valorization of the apple by-product through green technologies, such as ultraviolet-C radiation (UV-C), is in accordance with the increasing demand of natural and environmentally friendly products together with the reduction of waste generated worldwide. This study aimed to determine the effect of UV-C on the dietary fiber and antioxidant compounds of the apple by-product to enable its reintroduction into the food supply chain. The apple by-product was treated for 5 min with UV-C radiation and stored at 4 °C for 1 (D1), 4 (D4) and 7 (D7) days. Subsequently, dietary fiber composition, polyphenolic content, and antioxidant capacity analyses were performed. After UV-C treatment, it was possible to observe a significant ( p   <  .05) increase in the soluble dietary fiber across all samples compared to the control. For total dietary fiber, a significant increase ( p  < .05) was detected in samples D1 and D4. Furthermore, a significant decrease ( p   <  .05) in the insoluble dietary fraction was noticed. Regarding the polyphenolic content and antioxidant capacity, a significant increase was observed for all treated samples, although this increase was inversely proportional to the storage duration. Overall, UV-C irradiation proved effective in valorizing apple by-product by increasing dietary fiber and antioxidant capacity.