Enhancement of Antioxidant Quality of Green Leafy Vegetables upon Different Cooking Method

  • Hossain, Afzal (Food Technology Division, Institute of Food and Radiation Biology, Atomic Energy Research Establishment) ;
  • Khatun, Mst. Afifa (Food Technology Division, Institute of Food and Radiation Biology, Atomic Energy Research Establishment) ;
  • Islam, Mahfuza (Food Technology Division, Institute of Food and Radiation Biology, Atomic Energy Research Establishment) ;
  • Huque, Roksana (Food Technology Division, Institute of Food and Radiation Biology, Atomic Energy Research Establishment)
  • Received : 2017.05.15
  • Accepted : 2017.08.11
  • Published : 2017.09.30


Antioxidant rich green leafy vegetables including garden spinach leaf, water spinach leaf, Indian spinach leaf, and green leaved amaranth were selected to evaluate the effects of water boiling and oil frying on their total phenolic content (TPC), total flavonoid content (TFC), reducing power (RP), and antioxidant capacity. The results revealed that there was a significant increase in TPC, TFC, and RP in all the selected vegetables indicating the effectiveness of the cooking process on the antioxidant potential of leafy vegetables. Both cooking processes enhanced significantly (P<0.05) the radical scavenging ability, especially the oil fried samples showed the highest values. There is a significant reduction in the vitamin C content in all the vegetables due to boiling and frying except in the Indian spinach leaf. However, the present findings suggest that boiling and frying can be used to enhance the antioxidant ability, by increasing the bioaccessibility of health-promoting constituents from the four vegetables investigated in this study.


leafy vegetables;boiling;frying;antioxidant


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