Postharvest quality of 'Galaxy' apple fruit in response to Kaolin-based particle film application

Abstract

Kaolin-based film as Surround WP® was applied to 'Galaxy' apple trees to evaluate its effects on postharvest fruit quality. Following harvest, the Surround WP® on the fruit skin was either wiped off, or left unwiped, then, the fruits from these treatments along with fruits from non-Surround WP®-treated trees as the control were stored at 6°C for 100 days. Surround WP® film application reduced weight loss ratios during the period of storage while unaffecting firmness loss, sunburn index, starch conversion, and pH values. After 70 days of cold storage, fruits treated with Surround WP® film showed less diminution in soluble solids and titratable acidity. A taste panel identified minor quality differences between fruits coated with and without the film. Fruits coated with the film had the highest appearance rating, but also exhibited the lowest smoothness rating due to film residue. This study indicates that Surround WP® may be safely used for 'Galaxy' apples before harvest for retaining postharvest quality during cold storage.