Barrier and mechanical properties of methylcellulose–whey protein films

Abstract

Water vapour permeability (WVP) and mechanical properties were assessed in edible films prepared from methylcellulose (MC) and MC-whey protein isolate (WPI) or MC-whey protein concentrate (WPC). Glycerol (Gly) was used as the plasticizer. Two MC-WP films were formulated. For Group I films, the mass ratio of WP : Gly was constant, whereas for Group II films the mass ratio of polymer (MC + WP) : Gly was constant. The WVP of MC-Gly film decreased with increasing MC concentration, while the tensile strength (TS) and percent elongation (E) increased. The WVP of Group I and Group II films decreased erratically and TS increased when the MC concentration was increased. Group I films had higher TS values than Group II films at the same MC : WP ratios. E of both groups increased with increasing MC concentration (p < 0.05), excluding the films with the highest MC : WP ratio tested (0.8) in Group I films. Group I films had lower E values than Group II films at the same MC : WP ratios. MC effectively governed WVP, TS and E of the WP films. Generally, MC-WP films of this work showed lower WVP than that of MC-and WP-based edible films in the literature. This can potentially make MC-WP films a suitable film material for moisture-sensitive food products.

Preparation and properties of pullulan–alginate–carboxymethylcellulose blend films

“…Because these biopolymers are hydrophilic, their mechanical and barrier properties tend to weaken when exposed to elevated relative humidity (Lim, Mine, & Tung, 1998Yang & Paulson, 2000a). As a result, many studies aim at reducing the moisture sensitivity and enhancing the physical properties for these films, including the incorporation of hydrophobic components such as lipids into the film (McHugh & Krochta, 1994a;Perez-Gago & Krochta, 1999;Shellhammer & Krochta, 1997;Yang & Paulson, 2000b), blending with other less hydrophilic polymers (Dong, Wang, & Du, 2006;Erdohan & Turhan, 2005;Teramoto, Saitoh, Kuroiwa, Shibata, & Yosomiya, 2001;Wang, Yang, & Wang, 2003), chemical modification (Shingel, 2004;Teramoto et al, 2001;Xiao, Weng, & Zhang, 2002), and judicious use of plasticizer in the film formulation (Chick & Ustunol, 1998;McHugh & Krochta, 1994b). In some applications, rapid solubilization of film in water is desirable for certain products, such as mouth refresher film and dissolvable sachet for containment of pre-measured quantity of food ingredients.…”

Improving Physical Properties of Methylcellulose-Whey Protein Based Edible Film

“…Simple linear polymer chains, as in MC, can be packed tightly resulting in low permeability, but molecules with bulky side chains, as in proteins, are loosely packed and have high permeability (Chen, 1995). Gly is added to edible films to reduce brittleness and to increase flexibility, toughness and tear resistance (Erdohan and Turhan, 2005). It is also known that as the Gly content increases, the WVP of films is expected to increase.…”

“…Methyl cellulose (MC) was purchased from SigmaAldrich (Cat No 274429, Poole, UK). MC-WP films were prepared according to Erdohan and Turhan (2005). In Group A, MC was used at different ratios (0.3-0.8 MC/WP), as Gly/TP ratio (0.5) was kept constant.…”

Mechanical, barrier, and interfacial properties of biodegradable composite films made of methylcellulose and poly(caprolactone)

“…Plant-derived cellulose is already being used extensively in the paper and textile industries. [6][7][8] Methylcellulose (MC), a biodegradable polymer, is a modified type of cellulose, which is the most abundant biopolymer in nature. It is well known and of interest to be used as environment-friendly products, especially as coating or mulching film, because of its large availability, low cost, and easy processability.…”