Oral Presentation Joint Annual Scientific Meeting of the Nutrition Society of NZ and the Nutrition Society of Australia

Effects of legume addition and extrusion on the protein content and digestibility of a wheat-based snack (336)

Swapnil S Patil 1 , Charles S Brennan 1 , Susan L Mason 1 , Margaret A Brennan 1 , James D Morton 1
  1. Lincoln University, Christchurch, CANTERBURY, New Zealand

Background: Starch, protein and dietary fibres play a vital role in human nutrition. Plant-based foods such as cereals and legumes are rich sources of such nutrients.  Many researchers have focused on the importance of legumes (about 20 % protein) and cereals (about 50-60 % carbohydrate) in the human diet, as they have potential to meet the nutritional requirement of the increasing global population. This study was undertaken to evaluate the effects of the addition of legume flours into wheat-based extruded snack foods on the protein content and in vitro digestibility of protein of such blends.

Methods: Different proportions (5 %, 10 %, and 15 %) of green pea, yellow pea, chickpea and lentil flour were included in wheat flour based extruded snacks. Protein content was measured by the Dumas method, while in vitro digestibility of protein was determined by a two-step, two enzyme method that simulates digestion. The digested protein was calculated by measuring the difference in the protein content at the beginning and at the end of digestion.

Results: The addition of legumes to wheat-based extruded snacks increased the protein content by 1-2 %. Digestibility of extruded products was significantly higher than raw mixes prior to extrusion. For instance, the protein digestibility of extrudates was 60-65 %, whereas the protein digestibility of raw flour mixes was 28-35 %. The present result shows that hot extrusion technique has drastically increased protein digestibility of the snacks.

Funding source: N/A