Exploring the potential of flour, starch concentrate, and protein concentrate from Richlea lentils in the development of lentil based extruded puffs

Lentil puffs were developed from a mixed design of varying weight fractions of lentil flour (x1), lentil starch concentrate (x2), and lentil protein concentrate (x3) using a twin-screw pilot scale extruder at a dry feed rate of 20 kg/h (d.b.), a water feed rate of 2 kg/h, and an extruder screw speed of 350 rpm. Evaluations of the extrudate properties (expansion ratio, unit density), instrumental texture (hardness, crunchiness, and crispiness), and sensory properties (overall and texture liking, just about right (JAR), and check all that apply (CATA) were conducted, and the optimum lentil puff formulation was determined from sensory liking. Increasing x1 and x2 both increased the expansion ratio of the lentil puffs, whereas the interactions of x3 with x1 and x2 both reduced the unit density. All three formulation factors positively impacted the instrumental crunchiness and crispiness of the lentil puffs, whereas x3 had a larger impact on crunchiness, and x1 and x2 had a larger impact on crispiness. Lentil puff formulations with x3 ≥ 0.66 presented significantly lower sensory liking scores than those with x2 ≥ 0.33. The JAR test revealed that all lentil puff formulations were penalized for not having the right level of hardness, whereas the CATA test identified the crispy and crunchy attributes to positively correlate with overall and texture liking scores. The optimum lentil puff formulation was predicted from a maximum overall liking score of 6.1 and texture liking score of 6.7, to contain 50% (w/w, d.b.) of lentil starch concentrate and 25% of both lentil flour and lentil protein concentrate.