RESUMO
Carvacrol is well documented for its antibacterial and antioxidant effects. However, its high volatility has directed researchers toward nanoencapsulation technology according to bioeconomy and sustainability trends. This study examined and compared free carvacrol (FC), carvacrol microemulsion (MC), carvacrol microemulsion busted with chitosan (MMC), and carvacrol nanoemulsions (NC) as active coatings on extending minced pork meat shelf life at 4 ± 1 °C for 9 days, focusing on microbiological, physiochemical, and sensory characteristics. The research involved pre-characterizing droplet sizes, evaluating antioxidants, and determining antibacterial efficacy. The results demonstrated that NC with a 21 nm droplet size exhibited the highest antioxidant and antibacterial activity. All coatings succeeded in extending the preservation of fresh minced pork meat in comparison to the free carvacrol sample (FC). The NC coating showed the highest extension of minced pork meat preservation and maintained meat freshness for 9 days, with a lower TBARs of 0.736 mg MDA/Kg, and effectively reduced mesophilic, lactic acid, and psychotrophic bacterial counts more significantly by 1.2, 2, and 1.3 log, respectively, as compared to FC. Sensory assessments confirmed the acceptability of NC and MCC coatings. Overall, the carvacrol-based nanoemulsion can be considered a novel antioxidant and antimicrobial active coating due to its demonstrated higher efficacy in all the examined tests performed.
RESUMO
A new era is rising in food packaging and preservation, with a consequent focus on transition to "greener" and environmentally friendly techniques. The environmental problems that are emerging nowadays impose use of natural materials for food packaging applications, replacement of chemical preservatives with natural organic extractions, such as essential oils, and targeting of new achievements, such as further extension of food shelf-life. According to this new philosophy, most of the used materials for food packaging should be recyclable, natural or bio-based, and/or edible. The aim of this work was to investigate use and efficiency of a novel food packaging developed based on commercial LDPE polymer incorporated with natural material halloysite impregnated with natural extract of thyme oil. Moreover, a direct correlation between the stiff TBARS method and the easiest heme iron measurements method was scanned to test food lesions easier and faster. The result of this study was development of the LDPE/10TO@HNT film, which contains the optimum amount of a hybrid nanostructure and is capable to be used as an efficient active food packaging film. Furthermore, a linear correlation seems to connect the TBARS and heme iron measurements.
RESUMO
Starch (S) films containing gellan gum (90:10) and polyester (P) blend films (PLA:PHBV, 75:25) with and without ferulic, p-coumaric or protocatechuic acid at 2% (w/w) were obtained by melt-blending and compression moulding for the purposes of obtaining SP bilayers by thermo-compressing both monolayers together. These were characterised as to their mechanical and barrier properties and as to their performance as packaging materials for pork meat slices. The incorporation of phenolic acids promoted the water vapour and oxygen barrier capacity of bilayers while reducing their stiffness and resistance to break, mainly in the case of protocatechuic acid. Phenolic acids significantly improved the antioxidant capacity of the bilayer films, reducing the lipid oxidation of packaged meat during storage. Phenolic acid loaded bilayers also reduced the microbial counts of meat, mainly for lactic acid bacteria. These effects positively affected the development of the sample pH and colour parameters throughout storage. Active starch-polyester bilayer films exhibited great potential as a means of extending the shelf-life and improving the quality preservation of pork meat.