Biobased mineral-oil barrier-coated food-packaging films

Effect of whey protein isolate/chitosan/microcrystalline cellulose/PET multilayer bottles on the shelf life of rosebud beverages

Multilayer bottles consisting of chitosan (CS), microcrystalline cellulose (MCC), whey protein isolate (WPI), and polyethylene terephthalate (PET) were tested as novel materials for packaging and extending shelf life of rosebud beverages. We studied the storage stability at 4 °C, 25 °C, 37 °C, and 55 °C by assessing the physical and biochemical parameters. The results show that multilayer PET bottles had better barrier performance and improved soluble solids content, pH, polyphenol content, color indices, and browning degree in rosebud beverages over the control at all studied temperatures. A shelf life model was established based on the Arrhenius equation, and the number of days when polyphenol contents dropped to <50% of the initial content was defined as the shelf life. Our results highlight the reliability of the prediction model, and we conclude that packaging rosebud beverages in multilayer PET bottles significantly extends the product shelf life, and this benefit was further extended at low temperatures.

Nanocellulose Bio-Based Composites for Food Packaging

The food industry is increasingly demanding advanced and eco-friendly sustainable packaging materials with improved physical, mechanical and barrier properties. The currently used materials are synthetic and non-degradable, therefore raising environmental concerns. Consequently, research efforts have been made in recent years towards the development of bio-based sustainable packaging materials. In this review, the potential of nanocelluloses as nanofillers or as coatings for the development of bio-based nanocomposites is discussed, namely: (i) the physico-chemical interaction of nanocellulose with the adjacent polymeric phase, (ii) the effect of nanocellulose modification/functionalization on the final properties of the composites, (iii) the production methods for such composites, and (iv) the effect of nanocellulose on the overall migration, toxicity, and the potential risk to human health. Lastly, the technology readiness level of nanocellulose and nanocellulose based composites for the market of food packaging is discussed.

Multilayers assembly of bio-polyelectrolytes onto surface modified polypropylene films: Characterization, chelating and antioxidant activity

In order to remove the trace transition metal ions which catalyze the oxidation in food, chitosan (CS) and sodium alginate (ALG) multilayers were assembled on the polypropylene (PP) surface grafted with polyacrylic acid (PAA) to obtain PP-g-PAA/(CS/ALG)_n films. The morphology of the active films was observed, and the thickness of each single assembled layer was about 7 nm. The chelation ability of the films improved with increasing number of (CS/ALG)_n multilayers, and Cu²⁺ chelating quantity of PP-g-PAA/(CS/ALG)_15.5 films was about 3.4 umol/cm² for 72 h at pH about 5, improved by about 9.92 % as compared with PP-g-PAA films. In addition, the PP-g-PAA/(CS/ALG)_n films had chelation activity for both Cu²⁺ and Fe²⁺, suggesting the potentiality in antioxidant food package application.

Cellulose nanofibrils and silver nanowires active coatings for the development of antibacterial packaging surfaces

An active ink composed of cellulose nanofibrils and silver nanowires was deposited on flexible and transparent polymer films using the bar coating process, achieving controlled thicknesses ranging from 200 nm up to 2 μm. For 350 nm thick coating on polyethylene terephthalate films, high transparency (75.6% transmittance) and strong reduction of bacterial growth equal to 89.3% and 100% was noted respectively against Gram-negative Escherichia Coli and Gram-positive Staphylococcus Aureus bacteria using AATCC contact active standard test. Retained antibacterial activity was found with films produced by reverse gravure roll-to-roll process, showing the promising capability of this antibacterial solution to be deployed industrially. Finally, the same ink was also deposited on polylactic acid substrate to investigate barrier properties: for 350 nm thick coating, a reduction of 49% of oxygen transmission rate (dry conditions) and 47% reduction of water vapor transmission rate was noted, proving the enhanced barrier properties of the coatings.

A rapid screening method for evaluating the total migratable hydrocarbons in paper products by headspace gas chromatography

Herein, we report a rapid screening method for evaluating the hydrocarbon contamination in paper samples by headspace gas chromatography (HS-GC). This method was based on conducting the near-complete migratable release of hydrocarbons from a paper matrix to the headspace in 35 min at 98 °C. By programming the GC column temperature, other co-existing volatile organic compounds in the sample can be effectively separated from the migratable hydrocarbons. To simplify the method calibration, the concept of total migratable hydrocarbons was introduced and n-pentadecane was used as the standard hydrocarbon compound in the calibration. The results indicate that the present method offers good precision (the relative standard deviation < 9.8%) and accuracy (recovery between 94.3 and 101%). The present method can be a valuable tool for the quality assessment of total migratable hydrocarbons of paper products, aiming at providing a good guidance for safely using the recycled paper-based materials in various applications.

Herein, we report a rapid screening method for evaluating the hydrocarbon contamination in paper samples by headspace gas chromatography (HS-GC).