Water barrier properties of carboxymethyl cellulose/halloysite nanotubes nanocomposite to be used in food packaging applications

In this research, novel carboxymethyl cellulose (CMC) based nanocomposite film containing 5%wt of halloysite nanotubes (HNT) was fabricated via solvent casting method as a potential biodegradable packaging material. The performances of the nanocomposite packaging material was investigated by assessing the moisture content, moisture uptake, water solubility, water vapor barrier properties and opacity. The incorporation of 5%wt HNT into the film remarkably reduced the moisture uptake by ∼ 28.01% at 97% RH and 31.08% at 40% RH. Water permeability value of CMC/HNT film showed as 7.08 ± 0.26 × 10−11 gm/m2Pas at freezing, 3.37 ± 0.33 × 10−11 gm/m2Pas at refrigeration and 1.14 ± 0.00 × 10−11 gm/m2Pas at ambient environmental conditions respectively. Subsequent to the thermal annealing process, the water vapor permeation ability was drastically declined in the HNT added nanocomposite films at all three different conditions (freezing, refrigeration and ambient) due to enhancing the crystalline structure. Furthermore, the addition of nanofillers into the polymer matrix significantly induced the UV blocking property of the film. These findings disclosed that prepared CMC/5%HNT nanocomposite films can be a potential food packaging material.Keywords: barrier properties, carboxy methyl cellulose, halloysite nanotubes

Effect of packaging materials on the quality of oyster mushrooms (Pleurotus saijo caju) during storage

The study aims to investigate the optimal packaging material to maximise the restriction of physiological and biochemical changes which reduce oyster mushroom (Pleurotus saijo caju) quality during the storage after harvesting. There are six packaging techniques tested, including PET box, PET box with kraft paper, PET box with kraft covered by GreenMAP bag, soft tray covered GreenMAP bag, soft tray with kraft paper in GreenMAP bag, and kraft paper. The result shows that the PET box with kraft paper in the GreenMAP bag is the most suitable for the storage of oyster mushrooms. After 10 days under 4oC, the lowest weight reduction can be seen with only 5.78%, soluble protein declines 65.49%, and decrease of vitamin C with 27.87 mg/100 g. In addition, the fruit body can maintain the colour, structure, and taste better than those packed with other materials

Sustainable Bioactive Packaging Based on Thermoplastic Starch and Microalgae

This study combines the use of corn starch and Tetradesmus obliquus microalgae for the production of antioxidant starch films as flexible packaging material. Starch was plasticized with glycerol and blended with 1 w% polyallylamine chosen as an agent to modify the film physical properties. The addition of polyallylamine improved film water stability and water vapor transmission rate as well as mechanical stiffness and tenacity. The dried Tetradesmus obliquus microalgae, which showed an EC50 value of 2.8 mg/mg DPPH (2.2-Diphenyl-1-picrylhydrazyl radical), was then used as antioxidant filler. The addition of microalgae provided the films with good antioxidant activity, which increased with microalgae content increasing. To our knowledge, this is the first study reporting the development of sustainable bioactive packaging films composed of almost 100% starch, and follows the European union’s goals on plastics strategy concerning the promotion of bio-based, compostable plastics and the setting up of approaches to prevent food waste with a simple plastic packaging.

Production and characterization of bacterial cellulose-alginate biocomposites as food packaging material

Biocomposite of bacterial cellulose-alginate has been developed for use as food packaging material. This study aims to understand the physical and mechanical properties of the biocomposite produced from static fermentation of Gluconacetobacter xylinus InaCC B404 in media supplemented with alginate. The strain was grown in a medium containing alginate at a concentration of 0.4, 0.8, and 1.2% w/v at 30oC for 7 days. The SEM images showed that bacterial cellulose produced in a medium supplemented with alginate had a denser structure of fibril network and a smaller pore size than the control one. The structure change was due to interactions through hydrogen bonds between bacterial cellulose and alginate proven by FTIR spectra, resulting in a decrease in crystallinity and crystallite size of bacterial cellulose. It led to the decrease in tensile and tear strength of the resulting biocomposite. Alginate also causes biocomposite to have higher water vapour permeability values.