Effect of blend moisture and extrusion temperature on physical properties of everlasting pea-wheat extrudates

Abstract

The effect of everlasting pea in combination with wheat on physical properties and microstructure of extrudates were studied. The share of everlasting pea (Lathyrus sativus) was variable, at 35, 50 and 65 %, respectively. The everlasting pea-wheat mixtures were moistened to the required level (18, 21, and 24 %), homogenized, conditioned and extruded in twin-screw extruder with counter-rotating conical screws. All of the obtained extrudates were characterised by a slow degree of radial expansion and high specific density. The Pearson correlation analysis indicated a statistically significant linear Pearson correlation (p < 0.05) between chemical compositions of the blends and physical properties of the extrudates. The expansion ratio increased as the concentration of the fibers and proteins increased, while specific density and hardness decreased. Inverse relationship was observed for crude fat. The microstructure of the extrudates was determined by both the moisture of the blend and the process temperature. The differences observed in the size, number of air cells and in the cell wall shapes and thickness indicate possibilities of the modification of physical properties of everlasting pea-wheat extrudates. The extrudates produced from everlasting pea-wheat blends (50:50) at higher barrel temperature (110/140/180/170/130 °C) were characterised by more numerous air cells of smaller diameters. Increasing moisture content of extruded blends results in extrudates with a higher porosity. No significant effect was shown in the chemical compositions on the level of metal contamination in the extrudates. The application of a counter-rotating twin-screw extrusion-cooker in the study permitted the production of compact, hard everlasting pea-wheat extrudates for use in vegetarian lunch dishes.

Texturisation behaviour of peanut–soy bean/wheat protein mixtures during high moisture extrusion cooking

“…So that the SME was increased significantly when blending PPP with WG ( P < 0.05). Particularly, it increased from 836.40 to 881.82 kJ kg −1 ( P < 0.05) when the ratio of WG increased from 20% to 60%, which might be due to the viscosity increased and screw wear brought by the WG (Zarzycki et al ., ). The increase in the viscosity also indicated that higher degree of aggregation might occur in the PPP‐WG mixtures, which could entrap more water due to the greater effective volume of the aggregates (Zhang et al ., ; Wang et al ., ).…”

Extrusion parameters and physical transformations of an extrudate for fish: Effect of the addition of hydrolyzed protein flour from by-products of Oncorhynchus mykiss

“…When making a comparison of the results of EI and density, it can be stated that achieving a very low density does not necessarily imply a maximum expansion, as observed in Figures 3A, 4A, where the highest level of increase was completed at the point hydrolyzed protein flour 30% and moisture content 16%. Density and EI were negatively correlated in any extrusion process, behavior related to the distribution of cells inside the extrudate, size, and thickness of the walls that they form makeup (Zarzycki et al, 2015).…”

Extrusion of a Curcuminoid‐Enriched Oat Fiber‐Corn‐Based Snack Product

“…The effect of extruder feed moisture content on the breaking force of extrudates has been widely studied (Liu, Hsieh, Heymann, & Huff, ; Seth, Badwaik, & Ganapathy, ; Zarzycki et al., ). At a higher feed moisture content, the viscosity of the dough and mechanical energy in the extruder decreased, stopping the bubble growth at temperatures below the glass transition temperature (Kristiawan, Chaunier, Della Valle, Ndiaye, & Vergnes, ).…”