Nanoencapsulation with Eudragit® and chia mucilage increases the stability and antifungal efficacy of carvacrol against Aspergillus spp.

Carvacrol is a consolidated natural antimicrobial. However, its use in food is a challenge due to characteristic odour and high volatility. Nanoencapsulation has emerged to overcome these drawbacks. Aspergillus spp. represent a concern in grapes for causing rot and producing mycotoxins. This study aimed to evaluate the effect of carvacrol (unencapsulated and loaded into Eudragit^® and chia nanocapsules) on the growth of Aspergillus species. Spore germination and mycelial growth of Aspergillus spp. were evaluated using the agar dilution culture method. The stability of nanocapsules during storage was monitored monthly by evaluating the particle size distribution, polydispersity index, and zeta potential. Antifungal and antitoxigenic effectiveness of nanocapsules were assessed by counting fungal colony-forming units and determining mycotoxin levels in grapes. A dose-dependent effect of carvacrol (unencapsulated and encapsulated forms) on spore germination and mycelial growth was observed. During 180 days of storage, carvacrol into Eudragit^® nanocapsules preserved their nanometric dimensions, whereas chia nanocapsules maintained this characteristic for 30 days. The antifungal effectiveness of both encapsulated forms persisted for 210 days. No mycotoxin was found, even when fungal growth was not completely suppressed. Nanoencapsulated carvacrol proved to be a new promising antifungal product to ensure quality and safety in the grape production chain.