Widya Dwi Rukmi Putri, Deksa Aldebaran, Dona Fitria Anggraeni, Erryana Martati, Kiki Fibrianto
Purple sweet potato (Ipomoea batatas L.) is widely cultivated in Indonesia and has considerable potential as a functional food ingredient because of its high anthocyanin content. This study evaluated the effects of two drying methods, industrial-scale drum drying and traditional sun drying, on the physicochemical, structural, and functional properties of purple sweet potato flour from two local varieties grown in Indonesia (TW and IR). Drum drying, which involves high temperature and short drying time, produced flour with a lower moisture content (3.81%–3.89%) and higher anthocyanin retention (1.05–7.57 mg/g) compared with sun drying (6.27%–6.47%) and (0.59–1.17 mg/g). Microstructural analysis showed that drum drying induced starch pregelatinization, forming aggregated granules (28.94–52.90 µm) with no detectable crystallinity. In contrast, sun drying preserved more intact starch granules (12.50–23.16 µm) with detectable crystallinity (4.59%–5.04%). These results demonstrate that drying methods significantly affect purple sweet potato flour properties. © 2026 The Author(s). Published with license by Taylor & Francis Group, LLC.
Department of Food Science and Biotechnology, Faculty of Agricultural Technology, Universitas Brawijaya, Malang, Indonesia
