Antioxidant activity changes during hot-air drying of Moringa oleifera leaves

• Main Author: Wiwat Wangcharoen
• Format: Article
• Language: English
• Published: Maejo University 2013-09-01
• Series: Maejo International Journal of Science and Technology
• Subjects: Moringa oleifera; antioxidant activity; total phenolic content; browning pigment formation; hot-air drying
• Online Access: http://www.mijst.mju.ac.th/vol7/353-363.pdf

Dried Moringa oleifera leaf powder in capsule is now a popular food supplement in Thailand. To investigate its health benefits, antioxidant activities of M. oleifera leaves (3 varieties: Num Phrae, Ang Thong and PKM1) during drying in hot-air oven at 50C and 100C were studied by 3 different methods, viz. ferric reducing antioxidant power (FRAP), DPPH free radical scavenging activity and ABTS radical cation decolourisation, together with the determination of total phenolic content and browning pigment formation. It was found that the antioxidant activities and total phenolic content tend to decrease in the early stage of drying and then increase in the later stage, and that the dried leaves still have at least 60% of antioxidant activities compared to fresh leaves.