"Roasting good coffee is not that hard.
Roasting really good coffee is!"
Mark Hudon, co-owner, Hood River Coffee Co.
Roasting is serious business at Hood River
Coffee Co., because it determines the finished flavor of
the beans. And the roasting process is more complex than
one might think, combining math and science into a very
specialized art.
Hood
River Coffee Co. starts with only the highest quality green
Arabica beans from various parts of the world-the finest,
most flavorful beans in the coffee- industry. Mass market
coffee producers generally use less desirable, less expensive
Robusta beans, sacrificing flavor. The roasting process,
however, can change the characteristics of even the finest
beans for better or worse.
Many elements influence coffee roasting, and the techniques
used to control or adapt to the variations in these factors
can be more important than even the quality of the coffee
beans used.
At Hood River Coffee Company, Mark Hudon has created his
own automated roasting style based on the theories and formulas
of Carl Staub, chemical engineer and coffee guru of Reno,
Nevada. Staub's technique are based on knowledge that variations
in atmosphere affect how efficient roasting is. Differentials
in weather, air pressure, air density and moisture affect
coffee roaster efficiency, just like they affect the efficiency
of an automobile or airplane engine. For example, higher
altitude or humidity will require more roasting time to
create the same coffee beans as a lower altitude, low humidity
environment.
Staub discovered a chemical in all coffee beans that he
could track, and analyzed how the chemical is affected by
modifications in atmospheric conditions.
Simplified, what this means is that applying certain mathematical
formulas to roasting temperature and time, based on atmospheric
conditions on any given day will give you consistently roasted,
flavored coffee beans.
Mark has set the menu of implementing these formulas at
Hood River Coffee Co., to get the cup he and partner Peggy
have deemed the perfect brew for each variety of bean. Samples
of roasts are periodically ground and boiling water is added
for a testing process called "cupping," when the
aroma and flavor are evaluated for the slightest variations.
At Hood River Coffee Co., Mark has developed charts of recipes
and utilizes computerized roaster settings to control the
time and temperature of each individual roast, giving each
coffee what he considers a consistently optimum roast.
"We find the optimum roasting size for how efficient
our roaster is today. We look at altitude (which is a perceived
altitude that changes with air pressure/density), and temperature
to derive a "density altitude." This tells us
where the roaster is "at"-how it's operating in
the current climate.
Then Mark determines the density of each batch of beans-how
much moisture is in the beans. By weighing a volume, Mark
determines the BTT (best transition temperature) and the
MET (Maximum Environment Temperature), and programs them
into the roasting equipment.
The formula gives Mark the "drop temperature"-the
temperature the beans should be when dropped out of the
roaster and cooled.
The system records the bean temperature, while another instrument
checks environmental temperatures. To bring out different
flavors in beans, each type is roasted slightly differently.
The beans go through two "crack" stages during
the roasting. Initially, as the water within the beans begins
to boil, they expand a little, as moisture is released.
During the second crack, the sugars and oils in the beans
boil, eliminating some flavors and adding some flavors.
At these crack points, the beans give off little popping
noises, like popcorn.
The precise moment to end each roast depends on the type
of bean. The desired color and the amount of oil showing
are indicators. Because hot beans will continue to cook
a little after they are dropped out of the roaster, Mark
anticipates this in the timing.
For shipping, beans are vacuum-packed into valve bags. Oxygen,
which deteriorates coffee, is flushed from the bags and
replaced with nitrogen, an inert element which preserves
flavor and aroma. The valve releases gases the coffee beans
give off in the first 7-10 days after roasting.