Coffee: It’s in the Roast
Legends of Coffee
• How was coffee and its effects discovered?
– Goat herder legend
– Arabian sheik legend
World Map of Coffee
Major Components of
Green Coffee Beans
• Sucrose
– A sweet crystalline sugar C12H22O11 that
occurs naturally in most plants and is
obtained commercially especially from
sugarcane or sugar beets.
3 Major Components of
Green Coffee Beans
Chemical
Components
Sucrose
Cellulose
Trigonelline
Temperature
in Celsius
Effect Produced by the Respective
Temperature
170 ° - 200 ° C 1st Pop = Light carmelization, more
sugars remain
188 ° C
Most commonly accepted temperature
for 1st Pop
Major Components of
Green Coffee Beans
• Cellulose
– A polysaccharide (C6H10O5)x
of glucose units that
constitutes the chief part of
the cell walls of plants,
occurs naturally in such
fibrous products as cotton
and kapok, and is the raw
material of many
manufactured goods (as
paper, rayon, and
cellophane).
3 Major Components of
Green Coffee Beans
Chemical
Components
Temperature
in Celsius
Effect Produced by the Respective
Temperature
Sucrose
170 ° - 200 ° C 1st Pop = Light carmelization, more
sugars remain
188 ° C
Most commonly accepted temperature
for 1st Pop
Cellulose
230 ° - 280°
≤271 ° C
Trigonelline
2nd Pop = Cell wall fractured
Limits damage to cell walls and enhances
cup complexity
Major Components of
Green Coffee Beans
Trigonelline
– A colorless crystalline of
an organic base (alkaloid),
C7H7NO² obtained from
the seeds of fenugreek,
from certain other plants,
sea urchins, etc. It is the
N-methyl betaine of
nicotinic acid.
3 Major Components of
Green Coffee Beans
Chemical
Components
Temperature
in Celsius
Effect Produced by the Respective
Temperature
Sucrose
170 ° - 200 ° C 1st Pop = Light carmelization, more
sugars remain
188 ° C
Most commonly accepted temperature
for 1st Pop
Cellulose
230 ° - 280°
≤271 ° C
2nd Pop = Cell wall fractured
Limits damage to cell walls and enhances
cup complexity
Trigonelline
≥230° C
85% “bitter” element removed
A BALANCING ACT
Lower Temp / One Pop = More Sweet + More Bitterness
Higher Temp / Two Pops = Less Sweet + Less Bitterness
Other Chemical Elements Effect Results:
Many Different Oils &
Multiple Acids
Suggested Roasting Times for
Popcorn Popping Machines
• Light Roast
– Approximately 4 minutes
• Medium Roast
– Approximately 4.5 – 5.5 minutes
• Dark Roast
– Approximately 6 minutes
Activity Directions
• Have fun…
• Do not light yourselves on fire!
• As a group, determine the amount of time you will roast
the beans (light, medium, or dark roast)
• Place large bowl in front of popcorn popper’s air chute
• Designate oven mitt member and measure beans out in
butter lid
• Plug in air popper and let it warm up for 30 seconds
• Start timer and quickly pour beans into the air popper
• Immediately stir the beans with wooden spoon
Activity Directions cont.
• Place lid on popper and continue roasting to designated
time
– You can remove the lid occasionally to view the beans
• When you have reached the desired roasting time,
unplug the machine
• Using the oven gloves, quickly pour the beans into the
colander
– DO NOT FOR ANY REASON TOUCH THE BEANS
• Take the colander over to the garbage bin and sift the
beans to remove any remaining chaff
• After 10 minutes your beans should be cool enough to
touch and taste
Suggested Roasting Times for
Popcorn Popping Machines
• Light Roast
– Approximately 4 minutes
• Medium Roast
– Approximately 4.5 – 5.5 minutes
• Dark Roast
– Approximately 6 minutes