Extension of Quality and Shelf Life of Tomatoes Using Chitosan Coating Incorporated with Cinnamon Oil
Karthikeyan Venkatachalam, Somwang Lekjing, Paramee Noonim, Narin Charoenphun
Abstract
This study examined the effects of 2% chitosan (CS) coatings incorporated with varying concentrations of cinnamon oil (CO) (0%, 0.5%, 1.0%, and 1.5%) on the extension of the quality and shelf-life of tomatoes stored under ambient conditions. Control samples were untreated and coated with distilled water. All samples were stored for 14 days at 25 ± 1 °C, with quality assessments conducted every two days. The application of CS-CO treatments was notably effective in controlling weight loss (3.91–5.26%) and firmness loss (10.81–16.51 N), sustaining the color index score (11.98–16.78), and stabilizing the total soluble solids (4.64–4.71 brix), titratable acidity (0.374–0.383%), total phenolic content (75.89–81.54 mg/100 g), ascorbic acid concentration (21.64–33.69 mg/100 g), total antioxidant capacity (85.89–91.54%) and pigment levels, particularly chlorophyll (52.80–63.18 mg/100 g), compared to control samples (p < 0.05). Higher CO concentrations (1.0% and 1.5%) in the CS coating maintained a significant level of phytochemicals in the samples compared to the control group, while CS-CO at 0.5% performed similarly in preserving the other physicochemical qualities. Both CS and CS-CO treatments extended the shelf life of the tomatoes up to 14 days (<6.78 log10 CFU/mL), whereas control samples were only viable for storage for 6 days due to higher microbial growth (>7.8 log10 CFU/mL) (p < 0.05). Overall, CS-CO-treated tomatoes demonstrated superior quality preservation and shelf-life enhancement, with a notable improvement in overall qualities as compared to the CS and control samples.