LAUSR

Abstract Edible coatings of gum Arabic (GA) (6.0 and 8.0 %) with Shirazi thyme (Zataria multiflora) (0.3 and 0.5 %) were assessed as potential postharvest treatments to protect the quality of fresh in-hull pistachio when stored at 85 ± 5 % RH and 2 ± 1 °C for up to 36 days. The results showed that 6 % GA combined with thyme at the concentrations of 0.3 and 0.5 % decreased color change and PPO activity of fresh pistachio in comparison with untreated control fruits. Treated fruit (6 % GA alone with the addition of 0.3 % thyme) also had higher PAL activity and total phenolics. Higher free fatty acid and peroxide value were also found in fruits coated with GA (8 %) containing thyme (0.5 %). Both 0.3 % thyme and 6 % GA solutions were found to be the most effective on saturated and unsaturated fatty acids of kernel.