Preservation effect of chitosan and salicylic acid-based composite coatings on the postharvest quality of Lemons (Citrus limon L. Burm)

Lemon fruits undergo various quality changes during postharvest storage that reduce fruit quality. This study aimed to examine the effects of chitosan (CHI) and salicylic acid (SA) based composite coatings on various postharvest quality attributes of lemons stored at 6–8 °C and 90–95% relative humidity. The prepared coatings were characterized using the Fourier transform infrared spectroscopy and rheology. Results indicated that chitosan coatings enriched with salicylic acid effectively maintained the physiochemical and antioxidant properties compared to uncoated fruits. Among all treatments, the combination of CHI 2.0% and SA 2.0 mM maintained the highest ascorbic acid (458 mg L⁻¹), titratable acidity (5.23%), phenols (peel: 26.11 mg g⁻¹; pulp: 17.72 mg g⁻¹), flavonoids (peel: 2.49 mg g⁻¹; pulp: 2.29 mg g⁻¹), DPPH (peel: 42.66%; pulp: 34.91%) and OH radical scavenging activity (peel: 17.84%; pulp: 13.61%) by the end of storage. Additionally, fruits treated with CHI 2.0% + SA 2.0 mM exhibited reduced mass loss (5.28%). Overall, the study concludes that the CHI 2.0% + SA 2.0 mM combination showed promising results and can be used as an effective method for preserving the postharvest quality of lemon fruit.