Preparation and characterisation of films from xylose‐glycosylated peanut protein isolate powder

Abstract

Summary This work aimed at producing and characterising xylose‐glycosylated peanut protein isolate (PPI‐X) films by dissolving PPI‐X powder in water at ambient temperature and further plasticising with glycerol. The effect of powder dissolution temperature (20–100 °C) and glycerol concentration (15.0–45.0%, w/w) on mechanical properties and integrity of these films was quantified. The results showed that the powder dissolution temperature had no significant effect on the mechanical and water resistance properties of PPI‐X films within the temperature range tested. With increasing concentration of glycerol, the tensile strength and water resistance of PPI‐X films decreased and elongation increased. The films produced by dissolving the PPI‐X powder at 20 °C and plasticising with 25.0% glycerol had comparable mechanical properties and better water resistance compared to some other plant protein films plasticising with glycerol. The results suggested that PPI‐X films could potentially be used as biodegradable packaging materials.

Effect of xylose on the structural and physicochemical properties of peanut isolated protein based films

“…Numerous previous studies have indicated a signicant improvement of the functional properties of products coming from Maillard reaction between polysaccharides and proteins. 4,17 In order to determine the effect of glycosylation on structural properties of xylose-modied PPI powder, the degree of glycosylation (DG) with different xylose ratio was determined. As shown in Fig.…”

“…[6][7][8] In literature, several recent papers deal with the improvement of the mechanical and barrier properties of protein-based lms by glycosylation reactions. 4,9,10 Glycosylation with gum arabic 11 or glucomannan 9 increases the tensile strength, decreases the water vapor permeability of protein lms, but decreases the elongation ability. Generally, plasticizers having a smaller molecular weight show an easier incorporation into the protein matrix than plasticizers with a larger molecular weight.…”

“…12,13 They also exhibit a more efficient plasticizing effect and lead to a stronger and tighter protein networking with stronger intermolecular covalent bonds. Lin et al 4,7 reported that crosslinking with xylose increases the strength and elongation of peanut protein lms and also decreases quite remarkably their solubility in water. Therefore, xylose could be a good choice for the formation of protein-polysaccharides lms.…”

“…A previous study was focused on the optimization of pH, temperature and time of reaction to obtain the xylose glycosylated protein (PPI-X) solutions. 4 The effect of PPI-X dissolution temperature and glycerol concentration on mechanical properties and water solubility of glycosylated lms were also investigated.…”

“…4 Briey, peanut meal was dissolved in (1 : 10, w/v) deionized water, the pH of dispersions was adjusted to 9.0. Aer stirring with 150 rpm for 2 h at 25 C, the supernatant was obtained by centrifuging at 3500g for 10 min.…”