Influence of Whey Protein Addition and Feed Moisture Content on Chosen Physicochemical Properties of Directly Expanded Corn Extrudates

Abstract

Production of extrudates from cereals is an oftenused technological process in today's world food industry. Extrudates from corn flour produced using the twin-screw extrusion process and enriched with whey protein concentrate represent high-quality source of proteins and fats. Whey protein concentrate (WPC) as a valuable source of proteins and minerals is one of the highest-quality components for possible extrudate enrichment. In this paper, the influence of various WPC addition and some extrusion process parameters such as feed moisture content (Q H 2 O ) on physicochemical properties of directly expanded corn flour extrudates manufactured in twin-screw corotating extruder was investigated. Whey protein concentrate was added in the following ratios 7.5%, 15% and 22.5% and water in 10.08, 12.18 and 14.28 L/h. Final composition of products is determined with measuring of protein, fat and water shares, water absorption index (WAI) and water solubility index (WSI). With added WPC and with increase of water volume flow, there was a significant rise in total protein, fat and water content in final products, as well as lowering of WSI and rising of WAI indexes. The statistical analysis of the obtained data shows that the lowest WSI and the highest WAI had samples with the largest share of WPC (22.5%) and water volume flow of 14.28 L/h. Colour is measured for each sample, and results were represented with hue angle (H), chroma (C) and lightness (L) values. Process parameters, WPC and Q H 2 O

Effects of different blowing agents on physical properties of extruded puffed snacks made from yellow pea and red lentil flours

“…For red lentil extrudates, lightness, the reflecting diffusivity (scale from 0 to 100), significantly (p < 0.05) increased with N 2 injection, demonstrating that N 2 injection increased the lightness of red lentil extrudates. This increase in lightness in the presence of N 2 injection is in line with dry crispiness results (see Figure 4a), as extrudate structure, and cell wall thickness, potentially affect extrudate porosity (Amaya-Llano, Morales Hernández, CastañoTostado, & Martínez-Bustos, 2007;Barrett & Peleg, 1992;Brn ci c et al, 2011;Day & Swanson, 2013), and thus the extent of diffused reflection in addition to specular reflection (Seo, Cha, & Kim, 2009). It was previously reported that N 2 injection affects extrudate lightness due to the greater number of bubbles nucleated as a result of physical blowing agent-assisted extrusion (Koksel & Masatcioglu, 2018).…”

Correlations between the physical properties and chemical bonds of extruded corn starch enriched with whey protein concentrate

“…WSI had a negative correlation with WAI (r ¼ À0.634), which has also been observed by many other authors. 31,32 ER and WSI had a positive correlation (r ¼ 0.667). The insoluble aggregates formed by the cross-linking reactions between the protein and starch molecules disrupted the continuity of the starch matrix and led to lower ER.…”

Effects of process parameters on the properties of barley containing snacks enriched with brewer’s spent grain

“…In order to produce snacks with high protein content whey proteins have been previously used as additives in extruded snacks (Agbisit 2007;Allen et al 2007;Brnčić et al 2011;Cheng et al 2007;Kirjoranta et al 2012;Matthey and Hanna 1997;Onwulata et al 1998Onwulata et al , 2001aOnwulata and Konstance 2006;Taylor et al 2006). However, there are no published studies, in which whey proteins have been used together with BSG and whole grain barley flour.…”