Predication of Glycemic Response of Extruded Pulse Products Using In Vitro Analysis

Abstract

Whole pulses have been extensively studied for their favourable effects on post‐prandial glycemic control in several acute human studies. Despite the large body of evidence showing the glycemic control benefits of pulse flours and fractions, the optimal dose and combination of pulse flours and fractions that should be integrated into commercial products is unknown. Moreover, the impact of processing, such as extrusion, on glycemic response of pulse products has not been thoroughly examined. Accordingly, the current study used an in vitro model to predict the glycemic response of various pulse products, in order to identify potential formulations for human acute feeding trials. Test products comprised of pulse flours (pea, lentil, bean, chickpea) incorporated into extruded snack products at a rate of 40% (replacing corn ingredients). Pea fractions were added to extruded breakfast cereals both as individual ingredients (fibre vs. protein vs. starch) and in different combinations (e.g. fibre + protein; protein + starch; starch + fibre). Current study results showed that addition of pulse flours into extruded corn snacks led to a lower in vitro glucose release (g glucose/100g sample) over 360 min compared to an all‐corn extruded snack. While, combinations of fractions (fibre + protein and fibre + protein + starch) incorporated into extruded oat cereal had lower in vitro glucose release (g glucose/100g sample) over 360 min compared to all‐oat cereal. Analysis of raw material versus processed products showed that processing methods increased the level of starch damage and in vitro glycemic release. In summary, current study results indicate that incorporation of pulse flour or fractions into commercially processed food products will help to improve the glycemic profile of the products. This study results will aid in choosing the right pulse products for human clinical trials based on their in vitro response. Moreover, it will also provide processors with information on how processing influences the nutritional composition and the resulting glycemic response.Support or Funding InformationFunding from Alberta Pulse Growers and Saskatchewan Pulse Growers