Research on the effect of the ratio of beeswax, palm wax, and carboxymethyl cellulose (MW-CMC) on the physicochemical properties of film-forming preparation and the ability to preserve purple passion fruits

Abstract

The post-harvest passion fruit is a climacteric fruit prone to water loss, which leads to changes in its state, results in wrinkled skin, decreased sensory quality, and rapid spoilage within 5 to 7 days under environmental conditions. This research aims to investigate the effect of the ratios of the main components in the coating formulation (MW - CMC) from three materials: beeswax (1, 1.5, 2, 2.5, and 3%), carnauba wax (0.3, 0.6, 0.9, 1.2, 1.5%), and nano carboxymethyl (0.4, 0.6, 0.8, 1.0, and 1.2%) on the physicochemical properties of the film coating composition and ability to preserve purple passion fruit grown in Son La province, at a temperature of 5±1°C and relative humidity (RH) 90±2% for 48 days. The experimental results determined the appropriate component ratios of beeswax within 1.5 to 2.5%, carnauba wax from 0.6 to 1.2%, and carboxymethyl from 0.4 to 0.8%. The physicochemical properties of the film coating MW-CMC were stable with a pH from 7.8 to 8.2, viscosity from 10.31-61.59 cp, minimum zeta potential |ζ|>54.1 mV, particle size about 9.2 to 11.8 µm, and particle density of 2.9 to 3.2 million particles/ml. The experimental preservation on purple passion fruit results showed that respiration intensity peaked from 14.12-23.08 ml CO₂/kg.h on the 15th to 18th day with a corresponding ethylene production rate from 191.25-205.67 µl C₂H₄/kg.h; weight loss ratio from 1.92-3.42%; the sensory quality was maintained until the 48th day, achieving a score of 17.42 points.