Impact of Purslane (Portulaca oleracea L.) Leaves Extract to Enhance the Anti-oxidant Potential of Edible Oils during Heating

Abstract

The present work deals/ reveals with the effect of purslane leaves extract on the stability of soybean oil during heating and the acceptability of oil after preparation of poori (an Indian fried bread) by frying and its sensory evaluation. The ethanolic purslane leaves extract was blended with soybean oil at three different concentrations such as, 500, 1000 and 1500 ppm (T1, T2 and T3) and compared with control. The sample added with 100 ppm TBHQ was used as a positive control. Assessment of antioxidant activity of the ethanolic extract of purslane leaves was carried out by the estimation of total phenolic content, loss of β-carotene and antioxidant activity. The heating (173±2°C for 24 h; 8 h heating cycles per day) performance of soybean oil incorporated with purslane leaves extract was evaluated in terms of peroxide value, free fatty acid, total polar material and fatty acid composition. The thermal stability of the oils was evaluated using differential scanning calorimeter. The poori was prepared to check the acceptability of the oil. Results suggest that leaves extract of purslane (1500 ppm) may be used for obtaining reasonable thermal stability of soybean oil with acceptable sensory characteristics of the product. Although TBHQ showed almost similar thermal stability with leaves extract of purslane (1500 ppm), natural anti-oxidant is more preferred over synthetic anti-oxidant.