Experiment 1: Grind Size
For each treatment (coarse, medium fine):
1. Weigh 35g of coffee for each treatment (coarse, medium, fine) and add it to each French press.
2. On the stove, heat 5 cups of water to 85°C.
3. Quickly pour 1 ½ cups water into each French press. Be careful! The glass will be HOT.
4. Stir each mixture twice with a spoon and brew for 4 minutes, using a timer.
5. After 4 minutes, slowly press the plunger and pour coffee into cups.
6. Evaluate all treatments at the same time, when they are cool enough to taste. Each student should take 3 Styrofoam cups and rinse them after each experiment.
7. Pour any remaining coffee down the sink, and scrape the grounds out into the trash with a spoon.
Experiment 2: Temperature
For each treatment (70°C, 85°C and 100°C):
1. Weigh 35g of medium grind coffee for each treatment and add it to each French press.
2. On the stove, heat 3 batches of 2 cups of water to 70°C, 85°C and 100°C.
3. Quickly pour 1 ½ cups water into each French press. Be careful! The glass will be HOT.
4. Stir each mixture twice with a spoon and brew for 4 minutes, using a timer.
5. After 4 minutes, slowly press the plunger and pour coffee into cups.
6. Evaluate all treatments at the same time, when they are cool enough to taste. Each student should take 3 Styrofoam cups and rinse them after each experiment.
7. Pour any remaining coffee down the sink, and scrape the grounds out into the trash with a spoon.
Experiment 3: Contact Time
For each treatment (2 minutes, 5 minutes, 8 minutes):
1. Weigh 35g of coffee of medium grind coffee for each treatment and add it to each French press.
2. On the stove, heat 5 cups of water to 85°C.
3. Quickly pour 1 ½ cups water into each French press. Be careful! The glass will be HOT.
4. Stir twice with spoon and brew for each treatment time, using a timer.
5. After each treatment time, slowly press the plunger and pour coffee into cups.
6. Evaluate all treatments at the same time, when they are cool enough to taste. Each student should take 3 Styrofoam cups and rinse them after each experiment.
7. Pour any remaining coffee down the sink, and scrape the grounds out into the trash with a spoon.
1. In this lab we explored a number of ways to alter coffee extraction efficiency. If you brewed a weak cup of coffee, describe how you would increase the flavor strength of the next batch using insight you gained from the three experiments in todayâs lab. Explain why each method would increase your coffee flavor strength. (6 pts)
2. What flavor profile can you expect from coffee that was brewed using an excessively long contact time between the coffee and water? Why? (4 pts)
3. What flavor profile can you expect from coffee that was brewed using beans that were ground too coarsely? Why? (4 pts)
4. We used a burr grinder to grind the beans for todayâs lab. Describe how a burr grinder works (what are the parts, how does this control particle size?), and how it is different from a common propeller grinder? Aside from the particle size, what other detrimental effect can a propeller grinder have on the ground coffee? What affect do these factors have on extraction during brewing? (6pts)