Processing of PANCS to obtain flour

Abstract

Non-Conventional Food Plants (NCFPs) are vegetables that have parts with potential use in human food, such as roots, tubers, leaves, fruits, seeds, and others. Therefore, the objective of this work was to prepare flours from three species of NCFPs of economic value for agriculture in the western region of Paraná: *Raphanus sativus L.* (forage radish), *Ipomoea batatas* (sweet potato), and *Conyza spp.* (horseweed). For this purpose, the leaves of the NCFPs were subjected to the process of disinfection, blanching, drying, and milling to obtain the flours. Afterwards, the flours were characterized in terms of particle size, color, proximate composition, oxalic acid content, and the water absorption index (WAI) and oil absorption index (OAI). The results showed that the blanching process was effective in reducing oxalic acid content, resulting in a reduction of 23% to 93%. Regarding the proximate composition, the results varied between 9.7% to 11.3% for moisture, 15.4% to 24.7% for proteins, 0.9% to 2.23% for lipids, and 9.1% to 18.8% for ash. The largest percentage of the flour was retained on the 250 μm sieve (60% to 68.7%), with WAI of 9.6% and OAI of 11.1%, and colorimetry for L* 52.89 to 52.93, a* -4.40 to -4.75, and b* 17.80 to 17.86. The results demonstrated that the flours of the three NCFPs have satisfactory nutritional and color characteristics to make the products more attractive for consumption. Sweet potato leaf flour stood out for its nutritional characteristics, such as high levels of proteins and carbohydrates, and the lowest level of the antinutrient oxalic acid.