Did you know?
~ That Bean North uses Arabica coffee beans which have between 80-100 mg of caffeine per 5 oz. cup and
~ Robustas (your typical grocery store brand. Nabob, Folgers etc.) have up to 150-175 mg per 5 oz. cup!
~ The darker the coffee, the less caffeine. For example, a dark or French roast coffee has less caffeine than a medium roast coffee.
~ Espresso coffee has between 60-80 mg of caffeine per serving.
~ Coffee must have 97% of its caffeine removed to qualify as a decaffeinated coffee.
~ If 97% of the caffeine is removed from a Robusta bean (your Nabob, Folgers, Maxwell House, etc.) it will still a have more caffeine that the decaffeinated Arabica beans offered at Bean North.
~ Coffee beans have the caffeine removed before they are roasted, with the least effect on the flavour of the beans.
Swiss Water Process
To decaffeinate coffee beans by the Swiss Water method, a batch of green (unroasted) beans is soaked in hot water, releasing caffeine. This process is done until all the caffeine and coffee solids are released into the water. These beans are then discarded.
Next, the water passes through a carbon filter which traps the caffeine molecules but allows the water and the coffee solids to pass through. The caffeine-free water which comes through, known as “flavour-charged” water, is then put in a similar filtration device, and new coffee beans are added. However, since the flavor-charged water cannot remove any of the coffee solids from the new beans, only the caffeine is released. The process repeats, filtering out all the caffeine until the beans are 99.9% caffeine free. These beans are removed and dried, and thus retain most if not all of their flavour and smell.
Although the process originated in Switzerland in the 1930s, today the world’s only Swiss Water decaffeination facility is based near Vancouver, Canada.
This process is technically known as supercritical fluid extraction. With the CO2 process, pre-steamed beans are soaked in a liquid bath of carbon dioxide at 73 to 300 atmospheres, this removes the caffeine . After a thorough soaking, the C02 is removed and the pressure is reduced allowing the CO2 to evaporate, or the pressurized CO2 is run through charcoal filters to remove the caffeine. The coffee beans are then allowed to dry naturally.
CO2 works better than water because it is kept in supercritical state near the transition from liquid to gas so that they have the high diffusion of gas and the high density of a liquid. This process has the advantage that it avoids the use of potentially toxic solvents.
Why we use the processes we do
The World Health Organization found methylene chloride, the main solvent used in non-natural decaffination processes, to be a toxic chemical with effects such as reversible central nervous system depression and carboxyhaemaglobin formation. Additional effects reported were liver and renal dysfunctions, hematological effects, and neurophysiological and neurobehavioral disturbances. (The WHO Environmental Health Criteria Series, volume 164.)
The dangers of Methylene chloride in roasted coffee are debated as it evaporates at 104 degrees F (40 degrees C), and so would not survive the roasting process. Though residual methylene chloride does not appear to be present in roasted decaffeinated coffee, the chemical itself is dangerous to health so our organic certification does not allow it.