Effect of gelatin and salicylic acid incorporated in chitosan coatings on strawberry preservation

Strawberries are highly prone to rapid post-harvest deterioration due to their high nutritional content and lack of protective peel, demanding the development of alternative preservation methods. This study evaluates chitosan (CH) edible coatings enhanced with gelatin (GE) and salicylic acid (SA) for extending shelf life while maintaining fruit quality. Through atomic force microscopy, it was demonstrated that GE and SA showed increased surface roughness, besides improved the ultraviolet barrier properties and reduced water vapor permeability. Over 14 days of storage (3.0 ± 1.0 °C), all coatings minimized weight loss, firmness reduction, and color changes while delaying total soluble solids and pH increases. The effectiveness of the CH (0.8 %) with GE (0.2 %) and SA (2 mM) coating was mainly determined by the reduction of the development of natural disease development (84.30 ± 3.62 %), whereas the physicochemical properties tend to be similar in the assessed formulations. Principal Component Analysis (PCA) was used to investigate the effects of the treatments on strawberry shelf life and to determine the correlations between the responses studied. Considering the variability of the dimensions of the responses, correlation coefficients were used to form the matrix and extract the eigenvalue. PCA showed that the properties of the strawberries change continuously regardless of the treatments and indicated that four principal components accounted for 82.7 % of data variability. This study demonstrates that coatings, combined with cold storage, offer an effective solution for extending the shelf life of strawberries while preserving their quality throughout storage.