Sustained release of gaseous chlorine dioxide from alpha-cyclodextrin: An innovative method for strawberry preservation

The traditional method of generating chlorine dioxide (ClO 2 ) involves reacting sodium chlorite with acid on-site, posing high safety risks of concentrated ClO 2 . This study encapsulates ClO 2 molecules directly in α-cyclodextrin (α-CD) to form inclusion complexes (ClO 2 @α-CD). This approach enables stable storage and safe handling of gaseous ClO 2 , while its sustained-release property also provides long-term microbial inhibition. Fumigation with 0.25 g of ClO 2 @α-CD completely inhibited Aspergillus niger growth on potato dextrose agar (PDA). A 0.5 g dose reduced the 6-day decay incidence of A. niger -inoculated strawberries from 91.67 % (control) to 5.00 % and the severity from 58.75 % (control) to 1.25 %. In commercial storage simulations, 5 g of ClO 2 @α-CD reduced the natural incidence from 53.33 % (control) to 26.67 %, while preserving the weight, color, firmness, and total soluble solids (TSS)/titratable acidity (TA) ratio of strawberries. These findings suggest that ClO 2 @α-CD is a viable approach for controlling postharvest diseases and prolonging fruit shelf-life.