Physicochemical, Bioactive and Technofunctional Properties of Instant Black Mashua Flour Processed by Extrusion and Drum Drying

Black mashua (Tropaeolum tuberosum), also known as purple mashua, is an Andean plant with high nutritional and medicinal value. It has traditionally been used to treat prostate conditions. This study examined how the agroecological origin (Puno and Junín) and processing methods (extrusion and drum drying) affected the physicochemical, bioactive, and technofunctional properties of instant black mashua flour. Both factors were found to significantly influence the content of bioactive compounds and technofunctional behaviour of the flour. Although extrusion increased the content of total phenols, flavonoids, carotenoids, and total glucosinolates, it decreased the levels of vitamin C and anthocyanins, likely due to their thermal sensitivity. From a technological perspective, extrusion also resulted in higher bulk density, water absorption capacity, and swelling power. In contrast, drum drying produced higher water solubility and gelatinisation index values. Samples from Puno generally exhibited higher glucosinolate contents than those from Junín, while extrusion proved more effective in enhancing glucosinolate retention and improving functional properties. These findings suggest that the processing method should be chosen based on the specific bioactive compounds and technological functionalities that are prioritised in each agroecological zone.