Interactive Effect of Retrogradation and Addition of Pulses, Cooking Oil on Predicted Glycemic Index and Resistant Starch of Potato

Abstract

Potato is consumed as boiled, microwaved, baked, or fried and in combination with pulses and/or oils which might affect the postprandial blood glucose response. The effect of the combination of potato with pulses/oils followed by retrogradation is investigated on the predicted glycemic index (GI), resistant starch (RS), and related parameters. The addition of pulses to potato results in lowering of GI and enhancement of RS. Moreover, retrogradation (4°C for 48 h) of potato-pulse combination shows a GI lowering effect compared to control. Out of eight pulses, pigeon pea and kidney beans are more effective in lowering GI and increasing RS. The addition of oils to potato during cooking results in the reduction of GI and glycemic load (GL), with an increase in RS. Further, storage of cooked potato-oil combination at 4°C for 48 h results in the reduction of GI and increase in RS. Out of seven cooking oils, olive oil and ghee (clarified butter) bring about an effective lowering of GI and GL. The results suggest that the addition of pulses and cooking oil to potato, followed by cooling might be an effective approach in managing the postprandial rise in the levels of blood glucose.