Synergistic Coatings Based on Chitosan and Eugenia caryophyllata Essential Oil to Improve Postharvest Quality of Capsicum chinense

The topito pepper (Capsicum chinense) is a tropical fruit of economic and gastronomic importance in the Caribbean region, valued for its nutritional content. However, this fruit is susceptible to postharvest fungal diseases, including those caused by the phytopathogenic fungus Penicillium expansum, which can degrade fruit quality and pose a health risk due to the potential presence of mycotoxins such as patulin. In this context, we evaluated the protective effects of coatings with chitosan (CS), clove essential oil (CEO), and their combination (CS+CEO) on sweet peppers stored at 12 °C for 12 days after harvest. The results indicate that the film-forming solution exhibited an acidic pH (5.33–5.44), a density of ~1.0 g/cm3, and viscosities ranging from 2.75 to 32.9 cP. Furthermore, the results indicate that coatings with CS and CS+CEO significantly reduced weight loss, preserved firmness (19.12–30.40 N), and delayed ripening. At the same time, the coatings exhibited inhibitory effects on P. expansum and aerobic mesophiles. The CS+CEO combination demonstrated the greatest inhibitory effect, indicating that it is a sustainable and effective strategy for the postharvest preservation of sweet peppers, thereby enhancing their value, preservation, and food security in the Caribbean region.