Bacterial Nanocellulose-Based Active Packaging for Vapor-Phase Delivery of Cinnamaldehyde to Control Fungal Spoilage in Bread
Érika Leão Ajala Caetano, Joana Garrossino Magalhães, Nicolli Carriel de Souza, Jair Vaz Nogueira Junior, Angela Faustino Jozala, Denise GrottoActive packaging systems have emerged as a promising strategy to control microbial spoilage without direct incorporation of preservatives into food matrices. In this context, this study evaluated bacterial nanocellulose (BNC) as a nanostructured carrier for vapor-phase delivery of natural antifungal compounds in bread preservation. Cinnamaldehyde (CIN), cinnamon extract and clove extract were screened against Aspergillus niger, Penicillium chrysogenum, and Rhizopus microsporus using minimum inhibitory concentration (MIC) and inverted halo assays. CIN demonstrated complete fungal inhibition at 0.19% (v/v), corresponding to approximately 2.0 mg/mL, outperforming plant extracts, which exhibited limited and concentration-dependent activity. When incorporated into BNC at a 1:1 ratio (50% reduced loading), CIN maintained inhibition halos comparable to the free compound, indicating effective release and preserved bioavailability. The performance of the system was further evaluated in a bread model using a non-contact active packaging approach. Fungal growth in control samples was detected by day 6 (>105 CFU/g), while incorporation of plant extracts into BNC delayed spoilage to day 9 (≈50% shelf-life extension). In contrast, breads treated with CIN, either free or BNC-incorporated, showed no detectable fungal growth throughout 21 days of storage, corresponding to a shelf-life extension of at least 15 days. These results demonstrate that antifungal efficacy in vapor-phase systems depends primarily on the intrinsic potency of the active compound, while BNC acts as an effective carrier matrix that promotes sustained retention and functional availability of CIN. The use of BNC-based active packaging for cinnamaldehyde delivery represents a promising clean-label strategy to control fungal spoilage and extend the shelf life of bread without direct incorporation into the food matrix.