Pest control for green coffee bean importations is usually accomplished by fumigating the beans with methyl bromide (MB) in order to eliminate coffee leaf rust and the coffee berry borer, also know as Broca. But this chemical method of safely importing the beans poses a problem when it comes to organic coffee.
Methyl Bromide Is a Dangerous Chemical
Although MB completely disappears from the final roasted product, it is a very dangerous chemical, and its use is strictly regulated to reduce risks of human contact. Therefore, this gas is far from being allowed in the chain of organic certifications, and no organic coffee can ever be fumigated using MB, or it will lose its certification and added perceived value.
But there is more to the problem, especially for the state of Hawaii. Since Hawaii is the only coffee producing place in the world where Broca and leaf rust don’t occur, the state is very keen on protecting its crops, and all green coffee imported to the islands must be fumigated with MB. Since the Montreal Protocol designated MB as a toxic gas for the environment, a reduction of its use is encouraged, and Hawaii’s coffee importation is at stake. The coffee roasting and blending industry over there provides around 500 jobs and is worth over $116 million annually. If importations have to decrease due to the Montreal Protocol banning MB fumigation, a whole industry might perish, and its workers may lose their income.
Studying Ozone Fumigation
The United States Department of Agriculture(USDA)’s Agriculture Research Service (ARS), along with the University of Hawaii, have been prompted by the Hawaii coffee industry to develop an environment-friendly treatment that would efficiently kill coffee pests an that could even be certified organic. The research is oriented toward Ozone (O3) vacuum fumigation combined to 3 to 6 weeks quarantine.
Preliminary tests have been made on different stages of the Broca’s development, from egg to adulthood, and these tests have shown very efficient in killing the insects. Cupping tests have also been realized to make sure the ozone process didn’t impact the taste of coffee. The results indicated no significant difference in taste between the ozone-treated and the control samples. Further testing took place in order to balance the ozone concentration, vacuum level and exposure time of the process.
Similar mortality tests have been initiated on the coffee leaf rust, and this project, started in January 2007 and taking place in Tahiti, French Polynesia, will end July 31, 2008. If the results are as good as they were for the elimination of Broca, then ozone fumigation will be recommended by the ARS as an alternative to MB fumigation of raw coffee.