Efeitos da radiação gama na composição centesimal e de fenólicos em farinha de folhas e talos de batata-doce (Ipomoea batatas L. Lam)

Abstract

The growing demand for sweet potato and the increase in global consumption generate large volumes of waste, such as leaves and stems, which are often discarded. However, these parts have high nutritional and functional value, serving as sources of bioactive compounds such as phenolics, flavonoids, and antioxidants, which can help prevent and treat various diseases. Gamma irradiation has proven to be a promising alternative for enhancing preservation, microbiological safety, and the extraction of these compounds, in addition to being a sustainable technology that contributes to waste reduction and minimizes residue generation. In this study, sweet potato leaf and stem flours were subjected to gamma radiation doses (0, 0.5, 1.0, and 1.5 kGy) to evaluate their effects on physicochemical, microstructural, and bioactive properties, both before and after 150 days of storage. The results revealed that the centesimal composition showed statistical differences but no significant variations between the samples. The 0.5 kGy dose was effective in increasing the total phenolic content in leaves and stems, while the 1 kGy dose stood out for its stability of total flavonoids and antioxidant activity, as measured by DPPH and FRAP. When analyzing individual compounds by HPLC (High-Performance Liquid Chromatography), it was observed that 1.5 kGy was more effective for leaves, while 0.5 kGy yielded better results for stems, especially for chlorogenic acid and rutin. Microstructural evaluations indicated an increase in cracks, pores, and smaller particles in the irradiated samples. The application of gamma radiation proved to be an efficient strategy for enhancing the phenolic and antioxidant compounds in sweet potato leaf and stem flours, establishing them as promising ingredients for the development of sustainable food products with higher nutritional value and lower environmental impact.