Roasting coffee has been a fun and rewarding hobby of mine for the past 13 years. I still remember my first REAL cup of coffee – not the stuff you sip out of your mom or dad’s cup that is filled with sugar and fake creamer – but the first cup I ordered on my own, at a truck stop, just across the Michigan boarder, thick, black coffee. It was horrible! But, I was an adult and it was time to start an adult habit of drinking coffee.
But, Coffee doesn’t have to be horrible, and it all starts with the quality of the beans and where they were grown. I’ll talk about the beans on another post but for today let’s look at the steps to roasting coffee.
Now, roasting coffee and how the beans are roasted have a lot to do with how the coffee will taste after it is brewed or pressed. Again, when I roast coffee I always start with good quality beans; I get my beans from Theta Ridge Coffee located in South Bend, IN. Kevin has been a great guy to work with as it relates to his knowledge of beans and origin. For today’s post I will give you the Five Steps I use to Roast Exceptional Coffee
Step 1 – Measure the Beans
I sell my bags of coffee in 12 oz bags and I can roast enough coffee at one time to fill two bags. However, there is some roasting math that I need to account for – moisture loss. To get to 12 oz of roasted coffee I have to roast 14-15 oz of raw coffee depending on the darkness for the roast. Green coffee beans are dense with moisture and the roasting process “Cooks” the moisture out while caramelizing the natural sugars in the bean. I typically roast 1lb 15oz of coffee to produce 2-12oz bags.
Step 2 – Fill the Roasting Drum/Pre-heat the Roaster
I like to pre-heat the roaster to about 450-500 degrees. That temp will go down at the beginning of the roasting process and then climb back up.
Step 3 – Roast the Beans
This is where science is happening; Heating the beans to 465 degrees at just the right amount of time (too fast and the beans will be bitter, too slow and the roasting process will stall or the beans will turn to a carbon mess). The roasting temp at this point is reaching temps in the 500’s yet the beans are still around 350 – 425 degrees.
Step 4 – Cooling
Once the beans reach the ideal roast it’s time to remove them from the roaster and cool them as soon as possible. I want to STOP the roasting process fast. I use a large metal bowl with holes drilled in it, the bowl is in a 5 gl bucket that is connected to a shop-vac. The shop-vac then pulls cool air over the beans and extracts the chaff off of the beans – this process takes about 1 min (to get the beans down to about 100 degrees).
Step 5 – Packaging
The final step in the process is to weigh the beans and package them in a “breathable” bag. After the roasting process the beans will give off CO2 gas. Typically you should wait about 24 hours to enjoy the beans after the roasting process. Here’s what Bob Barraza from Home-Barista has to say about the CO2 “out gassing”:
So where did the CO2 come from? The coffee roasting process involves the oxidation or controlled burning of the coffee bean. In case you have forgotten, the oxidation of organic compounds results in almost entirely CO2 and water as the byproducts. Since CO2 is a gas at ambient conditions, the gas trapped in the beans will ‘boil off’ and slowly leave the roasted beans. Fresh roasted beans are loaded with CO2 , and they generally require about a day of ‘out gassing’ before they make excellent espresso.
And that’s how easy it is to roast coffee. I hope this post was interesting and helpful for you. For me, it’s time for another cup of coffee.