Effects of blending of neem seed oil, carvacrol, and eugenol in carnauba wax-based nanocoating on shelf-life extension of common mandarin

Nanocoating represent an effective postharvest technology for maintaining nutritional quality and extending shelf life of fruits and vegetables. This study investigated the effects of blending of neem seed oil, carvacrol, and eugenol in carnauba wax-based nanocoating extending postharvest quality and shelf-life of common mandarin. The nanocoating formulations (NCFs), having four different compositions, i.e., NCF1 (pristine carnauba wax), NCF2, NCF3, and NCF4, each containing 1 % (v/v) neem seed oil, carvacrol, and eugenol, respectively. The prepared NCFs exhibited uniform particle distribution with hydrodynamic diameters ranging from 235 to 490 nm. During storage, fruits treated with the NCFs, particularly the NCF3, exhibited significantly lower weight loss (11.71 %) compared to that in the control samples (21.72 %). The NCFs effectively maintained the key quality parameters, including total soluble solids, titratable acidity, ascorbic acid content, and antioxidant capacity, while reducing respiration and decay incidence in the coated fruits. Additionally, the NCF3 treated fruits retained greater firmness (8.04 N) than the control (1.97 N), and suppressed microbial growth i.e., 2.69 log₁₀ cfu/g in the coated fruits compared to 8.47 log₁₀ cfu/g in the control. These findings demonstrate that the developed NCFs, particularly NCF3 could be effective in extending shelf life of mandarin fruit.