Chitosan, produced through deacetylation of chitin from crustacean byproducts and, increasingly, fungal biomass and insects, is attracting food-sector interest because it combines antimicrobial activity, antioxidant capacity, biodegradability, and film-forming behavior in a single polymer. This review discusses how source, molecular weight (MW), degree of deacetylation, solubility, and charge density shape its performance in food systems. The paper then follows the main technological routes now tested or used: edible films and coatings, hydrogels, cryogels, nanoparticles, microcapsules, and hybrid matrices. These formats can protect fresh produce, meat, poultry, fish, seafood, and dairy foods, while also supporting beverage clarification, emulsion control, release of natural antimicrobials or antioxidants, and freshness monitoring in active or intelligent packaging. The evidence indicates strong promise, especially where microbial growth, lipid oxidation, moisture transfer, and short shelf life remain limiting factors. Yet, wider industrial use is still slowed by water sensitivity, sensory effects, raw-material variation, cost, process scale-up, and regulatory alignment. Future work should move beyond laboratory efficacy and address reproducible production, food-specific validation, and consumer acceptance.

Introduction: The COVID‐19 pandemic underscored the need to understand the zoonotic transmission of pathogens. SARS‐CoV‐2 has been reported to be transmitted from humans to pets, including cats and dogs, particularly after close contact with infected individuals. Studies have shown that cats are more susceptible to natural infection and can transmit the virus to other cats and humans. The zoonotic transmission route represents a risk for animal health workers. Despite global reports, data from Romania remain sparse. This study aimed to evaluate the presence of SARS‐CoV‐2 specific antibodies in household dogs and cats in Romania during the COVID‐19 pandemic. Methods: The study was conducted at a veterinary clinic in Iasi City, Romania, from March 2020 to December 2022. Blood samples were collected from 84 cats and 82 dogs that had been in contact with COVID‐19‐positive owners. Plasma samples were tested for anti‐SARS‐CoV‐2 antibodies using an ELISA test, followed by confirmation with a seroneutralisation (SN) assay. The SN assay used the SARS‐CoV‐2 MAD6 strain and Omicron strain to determine neutralising antibody titers. Results: ELISA testing showed a seroprevalence of 9.5% in cats and 11% in dogs. Further SN assay testing confirmed SARS‐CoV‐2 specific antibodies in 9.4% of cats and 2.4% of dogs. One cat maintained antibodies for over a year, though with reduced titers. Most cats' antibodies did not cross‐react with the Omicron strain, indicating limited cross‐reactivity. The study highlighted higher seroprevalence and antibody titers in cats compared to dogs, likely due to more efficient viral replication in cats. Conclusions: This study provides the first serological evidence of SARS‐CoV‐2 exposure in household pets during the pandemic in Romania, with findings suggesting cats are more susceptible to infection from their owners than dogs. The cats that were living in households in one area of the city were prone to be infected with SARS‐CoV‐2 from their owners and high levels of seroconversion were detected. These results align with global reports, demonstrating that cats are particularly susceptible to SARS‐CoV‐2 when living with infected owners.

Food additives are defining components of ultra-processed foods, yet microbiome-related effects remain largely outside routine safety assessment. This review evaluates evidence for six additive classes across four pathways—microbial community changes, altered microbial metabolites, mucus-epithelial barrier disruption, and immune modulation—and examines how these findings could inform microbiome-inclusive risk assessment. Mechanistic, translational, and epidemiological evidence was organized using a five-tier hierarchy: in vitro, ex vivo, animal, observational, and controlled human studies. Chronic-disease associations were graded across six domains by two raters using explicit criteria, with sensitivity analysis. Evidence was then translated into a tiered, decision-gated assessment protocol, illustrated with carboxymethylcellulose and back-tested against carrageenan, acesulfame K, and titanium dioxide, which return three different protocol outcomes. Non-nutritive sweeteners and emulsifiers have the strongest direct human and ex vivo evidence, including microbiome-dependent interindividual responses, although null and discordant trials remain. Gastrointestinal and metabolic outcomes received the highest support, cardiovascular associations were intermediate, and autoimmune, neurological, and psychiatric links remained preliminary. Metabolic and cardiovascular epidemiology relied largely on NutriNet-Santé, with modest hazard ratios (generally 1.03–1.15 per exposure increment) and indirect exposure estimation. Recent additive-mixture analyses from the same cohort were also considered. Food additives can act as context-dependent, microbiome-active exposures. Current evidence supports considering microbiome composition, barrier-integrity, and immune endpoints in additive safety evaluation, while causal links with most chronic-disease outcomes remain unproven.