Application of ethylene scavenging nanocomposite film prepared by loading potassium permanganate-impregnated halloysite nanotubes into low-density polyethylene as active packaging material for fresh produce

PBAT/PLA food packaging film containing sodium dehydroacetate-loaded diatomite as an antibacterial agent: Fabrication, water-gas regulation and long-acting antimicrobial mechanism

Biodegradable food packaging films with good antimicrobial properties are highly sought after for prolonging the shelf-life of fruits and vegetables whilst minimizing waste streams originating from the food sector. In this work, a series of PBAT/PLA food packaging films containing sodium dehydroacetate-loaded diatomite (SD/D) as an antimicrobial agent were fabricated. Structural analyses showed that the sodium dehydroacetate was incorporated into the pores of the diatomite. A uniform dispersion of SD/D in the composite films effectively enhanced water and gas permeability, whilst also giving the films good mechanical properties. The slow release of SD endowed the composite films with long-acting antibacterial ability (>90 % bacteriostasis rate for E. coli and >85 % bacteriostasis rate for S. aureus). The composite films were able to effectively maintain the quality of banana fruits during storage at room temperature, encouraging their use in food applications where non-biodegradable petrochemical-derived packaging films have traditionally been used.

Postharvest handling of ethylene with oxidative and absorptive means

Fruit ripening is an unfolding of a series of genetically-programmed modifications and tend to be highly orchestrated irrevocable phenomenon mediated by ethylene. Phytohormone ethylene also leads to over-ripening, senescence, loss of texture, microbial attack, reduced post-harvest life and other associated problems during storage and transportation of fruits. Its harmful impacts on fresh fruits, vegetables, and ornamentals result in substantial product losses even up to 80%. Curbing of this inevitable menace is therefore need of the hour. Accrual of ethylene in packaging system should fundamentally be ducked to extend the shelf-life and uphold an adequate superiority of perishables in visual and organoleptic terms. The current review discusses about properties, factors affecting and impact of ethylene, intimidation of its impact at gene vis-à-vis activity level using gene-modification/inhibition techniques, chemical/physical in conjunction with other suitable approaches. It also entails the most commercially cultivated approaches worldwide viz. KMnO4-based oxidation together with adsorption-based scrubbing of ethylene in thorough details. Future ethylene removal strategies should focus on systematic evaluation of KMnO4-based scavenging, exploring the mechanism of adsorption, adsorbent(s) behavior in the presence of other gases and their partial pressures, volatiles, temperature, relative humidity, development of hydrophobic adsorbents to turn-up under high RH, regeneration of adsorbent by desorption, improvement in photocatalytic oxidation etc. and further improvements thereof.

Graphical abstract

Supplementary Information

The online version contains supplementary material available at 10.1007/s13197-023-05777-1.

Photocatalytic chitosan-based bactericidal films incorporated with WO3/AgBr/Ag and activated carbon for ethylene removal and application to banana preservation

Ethylene (C2H4) and pathogenic microorganisms are the two major causes of the deterioration of postharvest fruits and vegetables (F&V). Hence, the development of active packaging with C2H4 scavenging and bactericidal activities is urgently desirable. Herein, a novel photocatalytic active film (CS-PC-AC) is developed for banana preservation by incorporating WO3/AgBr/Ag photocatalyst (PC) and activated carbon (AC) into chitosan (CS). The fabricated PC is a ternary Z-scheme heterojunction and its high photocatalytic activity is achieved by the bridge of Ag between WO3 and AgBr through rapid transfer and separation of photogenerated electrons and holes. AC plays an indispensable role in the photocatalytic reaction through molecule adsorption and transport. PC and AC are hydrogen bonded with chitosan and their incorporation has slight effect on film's thermal stability but decreases the film's mechanical and barrier properties to some extent. CS-PC-AC exhibits strong bactericidal activity (killing ~100 % of Escherichia coli and Staphylococcus aureus within 3 h) and good C2H4 scavenging activity (C2H4 scavenging rate of 49 ± 2 %) under visible light irradiation, which can extend the banana shelf-life by at least 50 % at 25 °C. These results indicate the good perspective of CS-PC-AC in the delay of the deterioration of postharvest F&V.

Potassium Permanganate-Impregnated Amorphous Silica-Alumina Derived from Sugar Cane Bagasse Ash as an Ethylene Scavenger for Extending Shelf Life of Mango Fruits

Ethylene, a plant hormone, is a gas that plays a crucial role in fruit ripening and senescence. In this work, a novel ethylene scavenger was prepared from amorphous silica-alumina derived from sugar cane bagasse ash (SC-ASA) and used to prolong the shelf life of mango fruits during storage. KMnO4 at 2, 4, or 6 wt %/w was loaded on SC-ASA using an impregnation method. The results showed that 4% w/w KMnO4 loaded on SC-ASA (4KM/SC-ASA) was superior for ethylene removal at an initial ethylene concentration of 400 μL L-1 for 120 min under ambient conditions (25-27 °C and 70-75% relative humidity), resulting in 100% ethylene removal. The kinetic study of ethylene removal showed that the adsorption data were best fitted with a pseudo-first-order kinetic model. The effects of 4KM/SC-ASA as sachets on the quality changes of the mango fruits were investigated, with the results showing that mango fruits packed in cardboard boxes with 4KM/SC-ASA had significantly delayed ripening, low levels of ethylene production, respiration, and weight loss, high fruit firmness, low total soluble solids, and high acidity compared to those of the control treatment. These findings should contribute to developing an ethylene scavenger to extend the shelf life of fruits, reduce the waste of the sugar and ethanol industries, and make it a valuable material.

Recent Progress of Biodegradable Polymer Package Materials: Nanotechnology Improving Both Oxygen and Water Vapor Barrier Performance

Biodegradable polymers have become a topic of great scientific and industrial interest due to their environmentally friendly nature. For the benefit of the market economy and environment, biodegradable materials should play a more critical role in packaging materials, which currently account for more than 50% of plastic products. However, various challenges remain for biodegradable polymers for practical packaging applications. Particularly pertaining to the poor oxygen/moisture barrier issues, which greatly limit the application of current biodegradable polymers in food packaging. In this review, various strategies for barrier property improvement are summarized, such as chain architecture and crystallinity tailoring, melt blending, multi-layer co-extrusion, surface coating, and nanotechnology. These strategies have also been considered effective ways for overcoming the poor oxygen or water vapor barrier properties of representative biodegradable polymers in mainstream research.

The Emergence and Impact of Ethylene Scavengers Techniques in Delaying the Ripening of Fruits and Vegetables

As the top grocery list priorities, the primary challenge when purchasing fruits and vegetables from supermarkets is obtaining fresh, minimally processed perishable goods. This source of diet is critical for obtaining vitamins, minerals, antioxidants, and fibres. However, the short shelf life caused by moisture content in rapid deterioration and decay caused by microbial growth, results in unappealing appearances. Fruits and vegetables undergo ripening and eventually the ageing process, in which the tissues of the plants degrade. Even after harvesting, numerous biological processes occur, generating a significant variation of ethylene production along with respiration rates between fruits and vegetables. Thus, the utilization of ethylene scavengers in food packaging or films has been revealed to be beneficial. The synergistic effects of these biomaterials have been demonstrated to reduce microorganisms and prolong the shelf life of greens due to antimicrobial activity, oxygen scavenging capacity, enzyme immobilization, texture enhancers, and nutraceuticals. The current review fills this void by discussing the most recent advances in research on ethylene scavengers and removal mechanisms of ethylene, including oxidation in fruit and vegetable packaging. The application and advantages of ethylene scavengers in packaging are then discussed with the addition of how the efficiency related to ethylene scavengers can be increased through atmospheric packaging tools. In this context, the article discusses characteristics, types of applications, and efficacy of ethylene control strategies for perishable commodities with the inclusion of future implications.