Effect of cooking methods on total phenolic content of Cleome Gynandra L

Abstract

The recent focus in research has been on functionality of foods to improve quality of diet and enhance health. Common chronic diseases such as inflammation, ulcers, diabetes, heart diseases, osteoporosis, are caused due to oxidative damage. The damage caused by oxidative stress or free radicals can be reduced by the consumption of antioxidants. Vegetables are rich source of antioxidants. Most vegetables are consumed after cooking. The cooking processes bring about a number of changes in physical and chemical composition of vegetables. Effect of cooking treatment on antioxidant properties of vegetables has seldom been reported. In the current study a locally available tropical vegetable Cleome gynandra was subjected to three cooking methods and its total phenolic content and antioxidant activity assessed. Boiling caused the highest loss in total phenolic content of Cleome gynandra, frying and steaming resulted into a higher concentration in total phenolic content compared to the raw vegetable sample. There was no significant difference in total phenolic content between the different cooking methods. Cooking resulted into a higher percentage of inhibition of DPPH compared to the uncooked sample. The highest percentage inhibition was observed in the steamed sample of Cleome gynandra while the lowest inhibition percentage was observed in the boiled sample. Cooking methods have a great impact on phytochemical and nutrient composition of vegetables. Appropriate cooking methods which require less water and less cooking time can be good for cooking vegetables to retain their nutritive value.