Packaging based on Ag-Low Density Polyethylene for shelf-life extension of pasteurized and traditional butters at refrigerated temperature

Abstract

This article focuses on increasing the shelf life of both pasteurized (Pa) and traditional (Tr) butters wrapped in Ag-Low Density Polyethylene (LDPE) film in concentration of 2.5%, 7.5%, 12.5%, and 17.5% at refrigerated temperature up to one month. Silver nanoparticles were synthesized (20.63 nm) through the chemical reduction followed by the melt mixing method to produce Ag-LDPE films. A mixed model-ANOVA Repeated Measurement presented that total bacteria, S. aureus and E. coli were eliminated from the Pasteurized butter samples wrapped with 17.5% Ag/LDPE films. In comparison, psychrophilic bacteria can be eradicated by 2.5-17.5% Ag/LDPE films after 30d. Peroxide value showed a slight fall from 0.50 and 0.28 meq/kg, respectively for Pa and Tr butters on the 1st day in the control group to 0.31 and 0.24 meq/kg, respectively in the butter wrapped with 17.5% Ag-LDPE film at the end of the storage with no significant difference (p > 0.05) with other treatments. Iodine value was decreased after 30d. It is concluded that the use of 17.5% Ag/LDPE as a coating of butter can safely preserve pasteurized butter at least a month.

Effect of thymol on physical properties, antimicrobial properties and fresh-keeping application of cherry tomato of starch/PBAT extrusion blowing films

“…Starch, PBAT and thymol were mixed to form the composite films. However, the hydrophilicity and hydrophobicity of the composite film are different, which result in obvious separation between components and voids in the matrix, which reduce the mechanical properties of the composite film (Wei et al, 2015;Pouyamanesh et al, 2022). Nordin et al (2020) explained that the incorporation of thymol as a lipid agent led to the heterogeneity of the film matrix, which might hinder the interaction between polymer chains.…”