Project Detail
Project Number
P 02-04
Project Leader
W. R. Witbooi
Institution
ExperiCo Agri-Research Solutions
Team Members
-
Student(s)
-
Date Started
March, 2004
Date Completed
September, 2008
Effect of methyl bromide fumigation as a phytosanitary treatment on the post-harvest quality of pears
Executive Summary
- The effect of methyl bromide fumigation applied at 64 g/m3 for 2 h at a pulp temperature of 7 to 10°C after packing (before simulated shipping), or 4 weeks after packing (simulating arrival overseas) on Forelle and Packham’s Triumph pears, was evaluated in 2004 and 2005, after a total storage period of 7 weeks at -0.5°C + 7 days at 10°C. The results showed that fumigation of pears after packing poses a higher risk for methyl bromide damage than if pears are fumigated upon simulated arrival overseas. Other quality disorders were not influenced by methyl bromide fumigation, although decay levels were slightly higher in methyl bromide treated fruit.
- During the 2006 season, Forelle pears were stored for 8 and 12 weeks under regular atmosphere conditions in bins at -0.5°C, packed in bags, and then fumigated with methyl bromide at different time intervals after packing (10 to 30 days after packing). Pear quality was evaluated after a total storage period of 7 weeks at -0.5°C + 7 days at 20°C. Although no methyl bromide damage occurred in any of the treatments, flesh firmness was generally lower in methyl bromide treated pears.
- In 2006, a semi-commercial Forelle pear trial was packed, exported, and fumigated with methyl bromide in the USA. Pears were evaluated after storage for 10 weeks at -0.5°C + 3 days at 20°C. Lower internal browning levels and slightly higher decay occurred on Forelle pears fumigated with methyl bromide. Other pear disorders were not influenced by the
- During the 2007 season, five populations of Forelle pears were fumigated with methyl bromide 4 weeks after packing, and then stored for an additional 3 weeks at -0.5°C + 7 days at 20°C. It was indicated that methyl bromide did not adversely afffect storage quality.
- In 2008, the use of SmartFreshSM on Forelle pears fumigated with methyl bromide enabled better maintenance of flesh firmness than when pears were not treated with SmartFreshSM.
- It was shown that it is better to fumigate Forelle and Packham’s Triumph pears with methyl bromide 4 weeks after arrival overseas than after packing (before shipment). The storage period after fumigation is critical to minimise storage disorders. SmartFreshSM treatment of Forelle pears fumigated with methyl bromide had a positive effect on maintaining storage quality.
For Final Report, please contact:
anita@hortgro.co.za