Development of third generation protein rich snacks from lentil and egg powder through microwave assisted extrusion cooking

Abstract

Purpose The purpose of this study was to formulate a complete protein food from lentil flour (LF) and egg powder (EP) through microwave-assisted extrusion technology. Design/methodology/approach In the first part of the hybrid technology, the feed proportion and extrusion conditions were optimized through design expert using central composite rotatable design. In the second part of hybrid technology, the optimized protein pellets (PP) obtained were subjected to microwave heating (MH) for 50,100, 150, 200 and 250 s. Findings The optimum predicted conditions for development of pellets using extrusion cooking were feed proportion (85% LF and 15% EP), barrel temperature (140°C), screw speed (340 rpm) and feed moisture content (12%). When these pellets were subjected to MH, 150 s of heating time was considered as prudential to induce desirable quality changes in PP. The increase in sectional expansion index, crispness and overall acceptability from 0.637 to 0.659, 4.51 to 6.1 and 3.27 to 3.59 with corresponding decrease in bulk density and breaking strength from 73.33 to 69.75 kg/cm3 and 6.24 to 5.13 N during 150 s of MH indicated that quality characteristics of extruded PPs were improved after MH. Practical implications Nowadays, consumers have become more health conscious than ever, and the demand for nutritious snacks has increased many folds. However, the high protein content restricts expansion of snacks, which was overcome by subjecting extruded pellets to MH to produce third generation pellets. Furthermore, the PP has a protein content of 31.62%, which indicates that if an average person consumes 100 g of these snacks, it will suffice 60% of total recommended dietary intake (0.75 g/kg body weight/day). Lentil-based pellets expanded by use of such hybrid technology (microwave-assisted extrusion cooking) can help to provide a feasible, low cost and protein-rich diet for malnourished population besides being a value addition to lentils. Originality/value LF in combination with EP was tested for the first time for development of nutrient dense pellets. Moreover, use of microwave-assisted extrusion cooking offers a workable and innovative technique of developing protein-rich pellets with improved physico-chemical and sensory attributes.

Effect of Extrusion Compression Ratio and Particle Size of Rice on the Sectional Expansion Index of Third-Generation Snacks

“…As can be seen, RG presented a higher volume mean diameter (D [4,3]) than did the RF (348 and 186.2 μm, respectively), corroborating the above-mentioned results. In total, 50% of RF presented a particle size of less than 178.9 μm; however, only 10% of RG presented a particle size of less than 170 μm.…”

“…In total, 50% of RF presented a particle size of less than 178.9 μm; however, only 10% of RG presented a particle size of less than 170 μm. Likewise, 90% of the RF particles had a particle size smaller than 313.9 μm, while only 50% of the RG particles had a particle size smaller As can be seen, RG presented a higher volume mean diameter (D [4,3]) than did the RF (348 and 186.2 µm, respectively), corroborating the above-mentioned results. In total, 50% of RF presented a particle size of less than 178.9 µm; however, only 10% of RG presented a particle size of less than 170 µm.…”

“…Likewise, 90% of the RF particles had a particle size smaller than 313.9 µm, while only 50% of the RG particles had a particle size smaller than 331 µm. These differences in particle size explain the existence of significant differences (p < 0.05) in D [4,3] and the standard percentiles between RF and RG.…”

“…However, it has been studied that using microwaves, in addition to avoiding the increase in fat content by not requiring oil, helps to better preserve the color, texture, and functional properties of the snacks compared to those under frying [2]. This reason may explain why recent studies have chosen microwaves as a method for the expansion of snacks from lentil and egg powder [3], beetroot by-products [4], blue corn, black bean, sweet chard [5], and Andean tuber and tuberous root flours [6].…”

Second generation extruded snacks from sweet chestnut and corn blends – numerical optimization, nutritional, nutraceutical and storage stability characteristics

“…Higher values of WAI with the increase in sweet chestnut flour proportion in the blend is due to the increased levels of starch in feed formulations, leading to improved exposure of hydrophilic groups of starch to water molecules, thereby allowing better moisture penetration into the porous extrudate structure (Seth et al, 2015;Delgado-Nieblas et al, 2015). Furthermore, WAI increased with the increase in feed moisture because water exerts a plasticizing effect on feed material during extrusion by reducing shear and, thus, limited degradation and gelatinization of starch, which consequently enhanced the water holding capacity of extrudates (Hagenimana et al, 2006;Yousouf et al, 2022). In addition, the Second generation extruded snacks plasticization of melt at higher moisture content caused a depletion of dough elasticity, thereby decreasing WAI (Ding et al, 2006).…”