The effects of different drying methods (hot-air drying, microwave drying and vacuum-freeze drying) on the antioxidant activity and antioxidants in sweet potato (lpomoea batatas L. Lain.) tubers were investigated ...The effects of different drying methods (hot-air drying, microwave drying and vacuum-freeze drying) on the antioxidant activity and antioxidants in sweet potato (lpomoea batatas L. Lain.) tubers were investigated to determine the potential drying process. Sweet potato tubers were cut into 5 mm thick slices, steamed at 100℃ for 10 rain, then dried in either hotair, microwave, or vacuum-freeze. The dried sweet potatoes in microwave possessed the highest antioxidant activity, while the lowest activity was observed in hot-air dried samples. The phenolic contents were positively correlated with scavenging activity and reducing power of DPPH^+. The microwave drying retains the highest antioxidant activity with the highest content of phenolic compounds in dried sweet potatoes. β-carotene and ascorbic acid showed minor contribution to the antioxidant activity in dried sweet potatoes.展开更多
基金supported by the Science and Technology Project of Zhejiang Province,China(2009C12031)
文摘The effects of different drying methods (hot-air drying, microwave drying and vacuum-freeze drying) on the antioxidant activity and antioxidants in sweet potato (lpomoea batatas L. Lain.) tubers were investigated to determine the potential drying process. Sweet potato tubers were cut into 5 mm thick slices, steamed at 100℃ for 10 rain, then dried in either hotair, microwave, or vacuum-freeze. The dried sweet potatoes in microwave possessed the highest antioxidant activity, while the lowest activity was observed in hot-air dried samples. The phenolic contents were positively correlated with scavenging activity and reducing power of DPPH^+. The microwave drying retains the highest antioxidant activity with the highest content of phenolic compounds in dried sweet potatoes. β-carotene and ascorbic acid showed minor contribution to the antioxidant activity in dried sweet potatoes.