Abstract
Pomegranates (Punica granatum L.) are highly perishable due to weight loss and particularly chilling injury (CI) such as skin browning (husk scald) and pitting when stored at temperature below 5 degrees C. The effects of pre-storage dipping in salicylic acid (SA) at 1.5, 2.5 or 3.5 mM and oxalic acid (OA) at 3.0, 5.0 or 7.0 mM for 10 min at 22 degrees C on quality and the incidence of CI during cold storage at 2 degrees C and 5 degrees C of 'Taify' pomegranates were investigated. Both SA and OA treatments at the all used rates significantly decreased the incidence of CI compared to the control. As the concentration of both SA and OA increased the CI decreased. In this respect, 7.0 mM OA was the most effective treatment. Storage temperature had no effect on CI. Weight loss increased during storage and was higher at 5 degrees C than at 2 degrees C. Membrane stability index (MSI %) was higher at 2.5 and 3.5 mM SA and 7.0 mM OA treatments than the control. However, the MSI % was not affected either by storage temperature or storage period but was greatly lower than the initial values. Firmness was not affected either by SA and OA or storage period but was higher at 2 degrees C than at 5 degrees C. Total soluble solids (TSS) concentration and pH were not affected either by SA and OA or storage temperature and period. Acidity concentration fluctuated during storage and was not affected by SA and OA but was higher at 5 degrees C than at 2 degrees C. Vitamin C concentration was not affected by SA and OA compared to the control, except for 3.0 mM OA treatment that was lower than the control. Vitamin concentration C fluctuated during storage and was higher at 5 degrees C than at 2 degrees C. There were significant interaction effects on vitamin C concentration between treatments and both of storage temperature and storage period. Total phenol concentration decreased during storage and was higher at 1.5 mM SA than other treatments. Soluble tannin concentration was not affected either by SA and OA or storage temperature but increased during storage. It was concluded that both SA and OA treatments could be suggested as practical tools for improving the storability of 'Taify' pomegranates under cold storage conditions.