Preparation and Application of Starch/Polyvinyl Alcohol/Citric Acid Ternary Blend Antimicrobial Functional Food Packaging Films

Abstract

Ternary blend films were prepared with different ratios of starch/polyvinyl alcohol (PVA)/citric acid. The films were characterized by field emission scanning electron microscopy (FE-SEM), thermogravimetric analysis, as well as Fourier transform infrared (FTIR) analysis. The influence of different ratios of starch/polyvinyl alcohol (PVA)/citric acid and different drying times on the performance properties, transparency, tensile strength (TS), water vapor permeability (WVP), water solubility (WS), color difference (∆E), and antimicrobial activity of the ternary blends films were investigated. The starch/polyvinyl alcohol/citric acid (S/P/C 1:1:0 , S/P/C 3:1:0.08 , and S/P/C 3:3:0.08 ) films were all highly transparent. The S/P/C 3:3:0.08 had a 54.31 times water-holding capacity of its own weight and its mechanical tensile strength was 46.45 MPa. In addition, its surface had good uniformity and compactness. The S/P/C 3:1:0.08 and S/P/C 3:3:0.08 showed strong antimicrobial activity to Listeria monocytogenes and Escherichia coli, which were the food-borne pathogenic bacteria used. The freshness test results of fresh figs showed that all of the blends prevented the formation of condensed water on the surface of the film, and the S/P/C 3:1:0.08 and S/P/C 3:3:0.08 prevented the deterioration of figs during storage. The films can be used as an active food packaging system due to their strong antibacterial effect.

Mechanical Physicial Properties of Chlorella-PVA based Bioplastic with Ultrasonic Homogenizer

“…Final residue after final heating of 600 o C of Chlorella-PVA based bioplastic film with ultrasonic pretreatment and Chlorella-PVA based bioplastic film without ultrasonic pre-treatment respectively are 5,03% and 1,32%. The heat application makes the Chlorella and PVA molecules through hydrogen bonding form more new structure thermal decomposition [7]. The same phenomenon was observed by Asada et al (2012) where the modification of bioplastic mixture improves the compactness of the crosslinkages within the material proven by the increase of residuals left after heating.…”

Recent Advances in Bioplastics: Application and Biodegradation

“…Similarly to the strategies used to improve the PLA characteristics, blending of starch has been widely investigated to improve its water resistance and mechanical strength. Starch was blended with polyvinyl alcohol; polycaprolactone; PLA; and non-biodegradable petrochemical polymers polybutylene succinate-co-adipate (PBSA), polybutylene adipate-co-terephthalate (PBAT), and polyethylene (PE) [230,[232][233][234][235][236]. The hydrophilicity of starch also represents a challenge when it comes to blending with hydrophobic polymers such as PLA.…”

Starch Based Bio-Plastics: The Future of Sustainable Packaging

“…Additionally, nanomaterials from titanium [50], magnesium, copper, silver [51] [52], platinum, gold and zinc have also received attention in antimicrobial food packaging due to their large surface-volume ratio [53]. Ternary blend films were prepared with different ratios of starch-polyvinyl alcohol with citric acid to obtain films with better antibacterial, mechanical, and thermal properties [54]. In other work two essential oils, Zataria multiflora Boiss (ZEO) or Mentha pulegium (MEO) at three levels (1%, 2% and 3% (v/v)), were incorporated into starch films using a solution casting method to improve the mechanical and water vapour permeability (WVP) properties and to impart antimicrobial activity.…”