Co‐extrusion of pearl millet‐whey protein concentrate for expanded snacks

Abstract

Summary A study was conducted to develop pearl millet‐based extruded snacks with whey protein concentrate (WPC) to enhance its acceptability and nutritional value. Pearl millet grits (841 μ) was extruded with different levels (0%, 2.5%, 5.0% and 7.5%) of WPC at constant feed rate (10.5 kg h−1) and moisture content (14%). Addition of whey protein at 7.5% level significantly (P ≤ 0.05) increased Tg from 75.1 ± 0.26 °C to 120.5 ± 1.28 °C and Tm from 89.1 ± 1.51 °C to 158.7 ± 1.37 °C, which resulted in less expanded and harder extrudates. The expansion index of extrudates was negatively correlated (P ≤ 0.05) with protein (r = −0.940), bulk density (r = −0.949), hardness (r = −0.971) and breaking strength (r = −0.921), while positively correlated (P ≤ 0.05) with overall acceptability (OAA; r = 0.988). Keeping in view the nutritional, textural and consumer's acceptability, incorporation of 5% WPC in pearl millet grits (841 μ) was recommended for preparation of acceptable expanded snacks.

Optimization of Extrusion Variables for the Development of RTE Snacks by Incorporation of Pearl Millet Starch

“…This might be due to lack of appropriate shear viscosity which unable to promote bubble growth and thereby making the product quite dense (Kristiawan et al, 2016). Similar results were noticed by Yadav et al, (2014) who reported that cell strength influenced by starch gelatinization and protein content. Hence, moisture content had significant effect on starch viscosity and physical attribute of extrudates (Gat and Ananthanarayan, 2015).…”

“…Pearl millet commonly known as bajra and termed as "nutricereal" due to presence of complex carbohydrates, protein of good biological activity, lipid, vitamins and minerals. It also contains high proportion of dietary fibers, and other phytochemicals with nutraceutical properties (Sihag et al, 2015 andYadav et al, 2014). However, it has remained as the food for poor and traditional consumers because of limited availability of ready-to-use or ready-to-eat pearl millet based products.…”

“…The losses of nutrients are lower than other thermal processing methods and also reduce the antinutritional factors (phytate, tannins and trypsin inhibitor) (Fellow, 2003 andFicarella et al, 2004). Pearl millet based extruded snacks blended with other cereals and legumes (Balasubranaian et al, 2012) and whey protein concentrate (Yadav et al, 2014) has been reported.…”

“…But pearl millet based extrudates had dense and hard texture, low expansion and low sensory score (Yadav et al, 2014) as compared to extruded snacks prepared from rice (Charunuch et al, 2011) and corn (Semasaka et al, 2010). Quality of the extruded product/snacks depends on the various controls of the extrusion process and proper manipulation of any, some or all the processing conditions through adoption of well-defined experimental design influence ultimate extrudate quality and functionality (Nor et al, 2013).…”

Extrusion Technology: Solution to Develop Quality Snacks for Malnourished Generation

“…Whey is the serum or liquid part of milk that is a by-product of cheese and curd manufacturing (stobaugh et al, 2016). Incorporation of 5% Whey Protein Concentrate (WPC) in pearl millet grits (841 µ) was recommended to develop nutritious acceptable extruded snacks (Yadav et al, 2014). Nutritious high-protein puffed snacks of corn meal with texturized whey protein isolate was developed with acceptable physico-chemical properties.…”