enhancing shelf-life and quality of ready-to-eat pomegranate arils with nanocomposite film: a pla/zno nanoparticle/zataria multiflora essential oil innovation

The dried pomegranate (punica granatum l.) arils have several health benefits and are in demand worldwide. beside this they are highly perishable due to their high water content and susceptibility to microbial growth, resulting in shortened shelf-life and compromised quality attributes. therefore, in the current study, the wrapping effects of poly l-lactide (pla) activated with zinc oxide nanoparticles (zno nps, 1.5% w/w) and zataria multiflora boiss. essential oil (zeo, 1 and 1.5% w/w) were studied on pomegranate arils' storage-life extension in cold storage. the arils were periodically analyzed for physiochemical properties (weight loss, ph, total soluble solids, color measurement, antioxidant activity, and sensory attributes) and microbial properties (total aerobic bacteria and total fungi counts). results showed that zeo caused a decrease in ph during storage, while zno caused an increase. the active films were more effective than the control film in maintaining tts and preventing weight loss of the arils. the pla/zno/1.5% zeo sample had the highest phenolic content (∼520 mg 100 ml^-1 in juice) and antioxidant activity (∼90%) on day 15. however, zeo had a greater effect on the color properties of the arils compared to zno, with 0.5% and 1.5% zeo-pla showing the highest a* (55.14) and b* (31.30) values with fresh arils, respectively. the microbial test results showed that zeo was more effective in controlling bacterial growth than zno. based on atomic absorption spectrophotometer measurement, minimal amounts (∼29 mg kg-1 sample) of zn2+ ions were observed to be released into the arils. overall, the active pla could be used as a safe and effective way to prolong the storage life of arils in refrigerated conditions.