Enhancing Mechanical Properties of Corn Bran Arabinoxylan Films for Sustainable Food Packaging

Abstract

Arabinoxylan (AX)-based films can improve the mechanical characteristics of biodegradable materials when utilized for food packaging. However, the mechanical properties of AX films for food packaging applications require thorough investigation to establish their viability. In this study, AX was extracted from corn bran coproducts of dry-milling (DCB), wet-milling (WCB), and dried distiller’s grains with solubles (DDGS) using an acid–alkali method. Packaging materials were produced using these AX extracts, each combined with laccase and sorbitol, forming the basis for three different films. These films were then modified by immersing the surface in a lipase–acetate solution. We evaluated their mechanical characteristics, including thickness, tensile properties, tear resistance, and puncture resistance. The thickness and tensile properties of the modified AX films derived from DCB and DDGS showed significant improvements (p < 0.05) compared to the unmodified AX films. In contrast, the modified AX films from WCB showed no significant changes (p > 0.05) in thickness and tensile properties compared to the unmodified WCB AX films. A significant increase in tear resistance (p < 0.05) was observed in all modified AX films after immersion in the lipase–acetate mixture. While puncture resistance was enhanced in the modified AX films, the improvement was not statistically significant (p > 0.05) compared to the unmodified films. The presence of hydroxyl (OH) and carbonyl (CO) groups on the surfaces of AX films from DCB and DDGS, modified by the lipase–acetate solution, suggests excellent biodegradability properties. The modification process positively affected the AX films, rendering them more bendable, flexible, and resistant to deformation when stretched, compared to the unmodified AX films.

Improving Biodegradable Films from Corn Bran Arabinoxylan for Hydrophobic Material and Green Food Packaging

“…Research bears out these results of the AX film morphology and water solubility [ 28 ]. The modified DCB AX and WCB films had lower surface fissures, resulting in lower water solubility for both modified DCB AX and WCB films compared to their unmodified AX films (DCB AX and WCB film morphology pictures not shown) [ 34 ]. The water solubility of the modified DDGS films remained unchanged as opposed to the unmodified DDGS AX film counterparts ( Figure 2 B).…”

“…A timed water method measured the vapor movement rate (every 30 min for 4 h, then at 24 h and 48 h) through the AX films. Because the 48 h measurement is the most effective for confirming the evaluation of WVTR and WVP, the following results section focuses on the measurement of water vapor permeability at 48 h. The thickness of the films tested in this work ranged from 88.9 to 104.1 μm [ 34 ]. It is important to note that the thickness of the films will play a role in the WVTR, and thicker films may have slower WVTR.…”

“…The extraction of the AX from the DCB, WCB, and DDGS samples was the same as that described according to the study of Alahmed and Simsek [ 34 ] and was performed in triplicate. The AX extraction procedure is concisely explained here including three main steps: defatting, acid–alkali extraction, and ethanol precipitation.…”

“…The procedure for casting AX films is mentioned in detail according to the former study of Alahmed and Simsek [ 34 ]; however, a brief description is provided here as well. The AX film was generated by dissolving the polymer in deionized water with D-sorbitol [ 33 ], with minor modifications.…”

“…The surface modification did not cause any visual differences in the film appearance ( Figure 1 ). In order to increase hydrophobicity of the AX films, the surfaces of the DCB AX, WCB AX, and DDGS films were immersed into a lipase–vinyl acetate solution [ 11 , 34 ]. The modified AX films were suspended in the reagent mixture for 24 h at 40 °C in an incubator [ 11 ].…”