Whole lentil flours exhibit their highest puffing ability at low processing temperature during extrusion

Primary Author: Pichmony Ek

Faculty Sponsor: Girish Ganjyal


Primary College/Unit: Agricultural, Human and Natural Resource Sciences

Category: Agricultural and Natural Resource Sciences

Campus: Pullman




Principal topic

Extrusion processing is commonly used to produce breakfast cereals and puffed snacks. These products are typically made from cereal flours with a high amount of starch which has high caloric bulk. Lentil is one of the attractive crops that can be used as an alternative ingredient for these products because of their high protein content and bioactive compounds. The source of raw materials including their varieties, can significantly affect the product qualities.


This study was to evaluate the qualities of the puffs made from three varieties of lentils (Brewer, Crimson, and Richlea). Whole seeds of the lentils were ground into flours and then processed with different extrusion processing conditions. Expansion ratio, water absorption index (WAI), and water solubility index (WSI) of the puffs were evaluated. The products with high expansion ratio (high puffing ability) generally provide crispy texture which consumers like. The products with low WAI could be produced as breakfast cereals because they can be crispy longer in milk and the products with high WSI are suitable for the foods for kids and old people.


The three lentils had relatively lower expansion compared to other cereals such as corn, but they exhibited their highest expansion at lower processing temperatures. Richlea variety was found to be the most suitable to produce these puffed products. The product characteristics of Crimson and Brewer varieties were comparable. The result of this study is useful for the food industry to select the lentil varieties for their specific products using extrusion.