Fabrication and application of buckwheat starch-based sustained-release composite films infused with curry leaf essential oil/β-cyclodextrin micro-capsules for preservation of green grapes.

The current research focused on developing a novel antimicrobial film composed of β-cyclodextrin (β-CD)-curry leaf essential oil (CLEO) micro-capsules in buckwheat starch (BS) and chitosan (CH) matrix for preservation and shelf-life extension of green grapes. The β-CD@CLEO micro-capsules were prepared by the co-precipitation technique and subsequently characterized. The encapsulation efficiency of β-CD@CLEO was 82.20%, and the outcomes of FTIR, TGA, and SEM revealed the successful micro-encapsulation of CLEO in micro-capsules. Various amounts of β-CD@CLEO (1%, 2%, 4%, and 8% w/w) were then added to the buckwheat starch-chitosan (BS/CH) composite films using the solution casting method. The films' physico-chemical, functional, mechanical, thermal, biodegradability, cytotoxicity, and micro-structural properties were thoroughly evaluated. Results showed that the addition of 4% w/w micro-capsules improved the hydrophobicity and functional properties of the composite (BS/CH) films. Furthermore, these films exhibited excellent mechanical and UV-barrier properties. The release behavior of the CLEO from the film was studied, and mathematical modeling showed that release behavior followed the Korsmeyer-Peppas model. All films showed excellent biodegradation and were non-toxic in nature. Green grapes were then packed with the film samples alongside polyethylene film for comparison. From several phyiso-chemical parameters and visual appearance, it was found that F5 film (BS/CH/β-CD@CLEO-4%) was able to prolong the shelf life of grapes to 25 days at refrigeration temperature (4 ± 1 °C). Overall, the fabricated BS/CH/β-CD@CLEO-4% multi-functional film offers a novel alternative to synthetic packaging used in preserving perishable items, thereby contributing to sustainable development. This development aligns with global efforts to promote eco-friendly materials and supports the transition towards a circular economy in the packaging industry. [Display omitted] • - • β-CD@CLEO micro-capsules were formed using a co-precipitation technique. • BS/CH composite films were infused with varying amounts (1%, 2%, 4% and 8% w/w) β-CD@CLEO micro-capsules. • Film with 4.0% (w/w) of micro-capsules showed maximum hydrophobic nature, UV- barrier and functional properties. • Films showed remarkable biodegradability and were non-toxic in nature. • Multifunctional films effectively enhanced the shelf life of grapes at 4 ± 1 °C. [ABSTRACT FROM AUTHOR]