Natural extracts and plant essential oils (EOs) have long been recognized as valid alternatives to synthetic food additives owing to their proved wide-spectrum antimicrobial capacity. The main aim of this study was to characterize the physical, mechanical, water barrier, microstructural and antimicrobial properties of chitosan-gelatin blend films enriched with cinnamon, citronella, pink clove, nutmeg and thyme EOs. The film microstructure determined by scanning electron microscopy, showed that all active films had heterogeneous surface: in particular, films including cinnamon, nutmeg and thyme EOs showed remarkable pores on the surface. The possible interaction of chitosan-gelatin blend film with incorporated EOs was investigated using Fourier-transform infrared (FT-IR) spectroscopy. Presence of new bands and changes in the FT-IR spectra confirmed intermolecular interactions between the chitosan-gelatin matrix and the EOs. The antimicrobial activity of films was determined using the disk diffusion assay. Active films inhibited the growth of four major food bacterial pathogens including Campylobacter jejuni, Escherichia coli, Listeria monocytogenes and Salmonella typhimurium and, among the tested EOs, thyme was the most effective (p<0.05).

Cold storage coupled with gaseous ozone represents a potential strategy to reduce or inhibit the presence of pathogenic and spoilage bacteria in a food storage cold chamber. This study aims to evaluate the impact of gaseous ozone treatment (0.05 ppm at exposure times of 30 and 60 min) on the bacterial contamination of internal surface and air in a cold chamber (3°C) intended for food storage. The bacterial load of internal surfaces was reduced by 0.99 ± 0.24 and 1.35 ± 0.27 log after 30 and 60 min ozone treatment, respectively. Airborne bacterial load was reduced by 0.93 ± 0.24 log after 30 min ozone treatment and became non‐detectable after 60 min. Gaseous ozone treatments (0.05 ppm at exposure times of 1, 2, 6, 24, 30, and 48 hr) of the cold chamber were investigated to evaluate the effectiveness of this technology against Escherichia coli, Listeria monocytogenes, Salmonella enterica Typhimurium, Campylobacter jejuni, and Pseudomonas fluorescens cultured in broth cultures. Ozone treatment was effective against C. jejuni since the population at the highest concentration of inoculum (3.34 log CFU/plate) was reduced by 2.23 log after 1 hr and it was completely undetectable after 2 hr. S. enterica and E. coli showed the highest resistance to short ozone treatment since 6 hr treatment did not show antibacterial activity whereas after 24 hr treatment around 2 log reduction was observed for both pathogens. Short ozone treatment did not affect L. monocytogenes viability. P. fluorescens showed high sensitivity to short treatments, with 0.75–1.32 log reductions after 1 hr and further 0.22–0.53 log reductions after 6 hr.

Recently, academic research and industries have gained awareness about the economic, environmental, and social impacts of conventional plastic packaging and its disposal. This consciousness has oriented efforts towards more sustainable materials such as biopolymers, paving the way for the “green era” of food packaging. This review provides a schematic overview about polymers and blends of them, which are emerging as promising alternatives to conventional plastics. Focus was dedicated to biopolymers from renewable sources and their applications to produce sustainable, active packaging with antimicrobial and antioxidant properties. In particular, the incorporation of plant extracts, food-waste derivatives, and nano-sized materials to produce bio-based active packaging with enhanced technical performances was investigated. According to recent studies, bio-based active packaging enriched with natural-based compounds has the potential to replace petroleum-derived materials. Based on molecular composition, the natural compounds can diversely interact with the native structure of the packaging materials, modulating their barriers, optical and mechanical performances, and conferring them antioxidant and antimicrobial properties. Overall, the recent academic findings could lead to a breakthrough in the field of food packaging, opening the gates to a new generation of packaging solutions which will be sustainable, customised, and green.

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An agronomic strategy to mitigate climate change impact can be the build-up of soil organic carbon. Among agronomic management approaches, the administration of organic fertilizers like livestock manure represents an effective strategy to increase soil organic carbon. However, livestock manure usually contains a high amount of water, reducing its sustainable delocalization and impacting on greenhouse gas emissions and nutrient leaching. Furthermore, the possible presence of weed seeds and harmful microorganisms could reduce the agronomic value of the manure. To overcome these issues, the combined effects of dewatering, composting and pelleting were investigated on livestock manure to produce sustainable organic fertilizers. Our results showed that composting and pelleting can represent a feasible and sustainable solution to reduce the potential risks related to the presence of weed seeds and harmful bacteria, concentrating nutrients and allowing a sustainable valorization and delocalization of the livestock manure. In addition, the processed manures were assessed as fertilizers in the growing medium (GM), displaying an increase in water retention and nutrient availability and a decrease of GM temperature and weed seed emergences. However, further study is needed to validate, both in open field and greenhouse productions, the effects of the proposed fertilizers in real cropping systems.