Effect of pretreatments and drying temperatures on sweet potato flour |
| |
Authors: | Maruf Ahmed Akter Mst. Sorifa Jong Bang Eun |
| |
Affiliation: | Department of Food Science and Technology, Chonnam National University, Gwanju, South Korea, Korea |
| |
Abstract: | Effect of pretreatments with 1 w/v% sodium hydrogen sulphite (NaHSO3) and 1 w/v% calcium chloride (CaCl2) and drying temperatures (55, 60 and 65 °C) on sweet potato flour were investigated. Flour treated with CaCl2 had higher amounts of ascorbic acid and β‐carotene (10.61–12.54 and 3.26–3.46 mg 100 g?1 wet basis, respectively) than that treated with NaHSO3 (9.47–11.47 and 3.05–3.43 mg 100 g?1 wet basis, respectively). Total phenolic content and water absorption index (wet basis) were highest at 65 °C when treated with NaHSO3 (10.44 mg 100 g?1 and 2.49 g g?1 respectively) and CaCl2 (9.52 mg 100 g?1 and 2.85 g g?1 respectively). Swelling capacity (wet basis) was highest at 60 °C when treated with CaCl2 (2.96 g g?1) whereas when treated with NaHSO3 (2.85 g g?1) it was highest at 55 °C. Freeze‐dried samples treated with NaHSO3 had higher lightness and total phenolic content while CaCl2‐treated samples had higher β‐carotene and ascorbic acid. The results showed that good quality flour could be produced after soaking in CaCl2 and dried at 65 °C. |
| |
Keywords: | Calcium chloride chemical composition freeze‐drying hot air‐drying sodium hydrogen sulphite sweet potato |
|
|