Mild Vacuum Packaging for Long Storage of cut Danae racemosa (L.) Moench Foliage

Cut foliage is used as fillers to improve the appearance of bouquets or floral decorations. The growing season in Italy is comprised from September to May. Therefore, there is a period of product unavailability. The commercial cooperatives and floral industries are very interested to extend as much as possible the period of storage. The aim of this work was to evaluate the use of mild vacuum as potential storage system for cut Danae racemosa foliage. The cut foliages were stored at 4°C in distilled water as control and in plastic bags with reduced atmosphere using vacuum packing machines (vacuum ranged from 0.1 to 0.5 MPa). After 30, 45 and 60 days of storage, the cut foliages were transferred to 20°C in controlled environment for vase life evaluation. Immediately after storage, the chlorophyll a fluorescence and sugar (reducing sugars and sucrose) contents were measured. The vase life of cut foliage evaluated immediately after harvest was 35 days. After 30 days of storage the vase life was 30 days in the control and 28 days in mild vacuum stored foliage. After 45 days the vase life declined and was in average 21 days in both storage treatments. After 60 days of storage, the vase life in control was 15 days and in mild vacuum treatment was 10 days. The results of chlorophyll a fluorescence showed that the cut foliage were more stressed in mild vacuum than in control and that probably explains the reduction of vase life. The reducing sugars were not affected by the storage treatments, while sucrose content was higher in mild vacuum stored foliage especially when stored for 45 and 60 days.