Home roasting coffee for a more delicious caffeine habit

Guest post by Rachel B.
Photo by Silke Gerstenkorn. Used under Creative Commons license.

Coffee. I can’t be functional without it. I hate to say that, but I have an addiction. My husband Tom and I took on a challenge: we aren’t buying food at grocery stores or restaurants for a year. That also meant no more chain coffee shops. I had to find an alternative.

On honeymoon in the UK, one of the things that struck me was just how good the coffee was at the bed & breakfasts we stayed at. It wasn’t bitter like the coffee in the US. It was smooth and nutty with hints of caramel. I was suddenly extremely disappointed in my coffee options at home, so I started researching how I could get that flavor on my own. I haven’t reached the exact flavor, but I come pretty close: I buy beans green at specialty stores — allowed in our rules — and roast my own coffee.

Coffee roasters aren’t cheap and reviews suggest they’re often short lived. Then I learned it’s possible to roast coffee in an air popcorn popper. We have an old popper that’s seen better days; it’s probably 20 years old and the bright yellow plastic has now turned brown from heavy use roasting beans.

Roasting coffee only takes a few supplies:

Roasting the beans:

  1. Add one cup of green beans to your popper. The beans should just reach the top of the rotating “drum” inside.
  2. Turn on popper. Never ever leave the popper unattended. It gets very hot and can catch fire very easily.
  3. Listen for the beans to begin making sound. This is called the “first crack.”
  4. You will notice that the popping sound slows and stops for a little bit; “second crack” is when the beans pop again. You will notice that this popping has a slightly different sound than the first crack. This is when you need to really pay attention.
  5. At this point it’s called a “city roast.” I prefer to roast 30 seconds into the second crack. You can roast it all the way to an Espresso roast, but it will change the flavor. Lighter roasts are less bitter.
  6. It takes us about eight minutes to roast the coffee from start to finish, but it will probably vary depending on your popper. As you keep roasting, the beans become shiny — the pops you’ve been hearing are caused be fissures releasing oil from the bean.
  7. Unplug the popper. With the pot holders, carefully but quickly pour the beans into the colander. Be careful! The beans are around 450 degrees F.
  8. Put the colander on the fan and swirl your beans. You want to cool them off as quickly as possible to prevent continued roasting.
  9. The beans should have expanded by about 50%. Put them in an unsealed jar and let them sit overnight to rest and release built up gases.
  10. Brew away!

When you roast, remember these suggestions:

  • Only grind your beans right before you use them. You spent all this time roasting them and you don’t want to waste it by grinding them ahead of time.
  • When buying an air popper to roast beans, make sure you buy one which rotates when heating. You want the beans constantly moving.
  • New poppers seem to burn out after six months of regular use, so I buy them at thrift stores. They are a dime a dozen. You can also use a stovetop popper.
  • You can buy beans online or from some homebrew shops. I recommend getting a sampler pack for your first time. There are a mindboggling variety of beans out there — so start simple. There’s nothing worse than buying a five pound bag of beans, only to learn you hate that breed.
  • Roast coffee outside. Roasting can be incredibly smoky and poppers often blow the bean chaff all over the place.
  • If it’s too cold outside or you don’t have a good roasting spot, at least roast under a stovetop hood — and use your colander to catch the chaff.

And that’s all it takes to become a home roaster.

Comments on Home roasting coffee for a more delicious caffeine habit

  1. I do this! I’ve had some issues with bitterness, but I think that’s because I’ve roasted too long. I’m definitely a “novice” roaster. A very dear friend of mine has been roasting for years, and her coffee is fantastic, so she got me a new popcorn popper and some green beans as a wedding gift!

    I’d also like to note (for those of us who have to pop on the patio, dude to sensitive fire alarms) temp and humidity level can affect roast time.

  2. Bitterness can also result in how you extract your coffee. If you are using an espresso machine it can depend on how long you pull your shot. If you are using a drip coffee machine or bodum make sure you are grinding on the more coarse side for bodum and fine side for espresso machines. It also depends on the humidity. If you really into doing home coffee I suggest a burr grinder.
    There are lots and lots of factors into the taste of coffee other than the roast itself. Just my two cents of being a former barista.

  3. I would never have thought of home roasting, but now I will give it a try! We’re always on the hunt for a better coffee, and the idea of doing any food task in a less manufactured way makes me even more excited.

  4. Woot, awesome post Rachel! We had an iRoast2 until I broke the roasting chamber during our move last year. We’re looking to buy another this summer as replacing the chamber is almost as much as buying a new one.

    Personally, I like to wait a day until we grind(burr grinders really do make a difference)/drink the batch we’ve just roasted as the flavors seem to set in a bit more, but that’s just our personal taste.

    Here are two of our favorite online supply sites:

    Anyone living in Atlanta can get green beans at Dekalb Farmers Market. They don’t have a huge variety but it’s enough to sample the different types of beans and how they roast.

  5. I used to work at a coffee shop for a retired marine who roasted his own beans. Even *I* like that coffe (oh he did some Kona coffee that was absolutely heavenly). It makes such an unbelieveable difference.

  6. I am so inspired by your plan to eschew grocery store and restaurant purchases for an entire year!

    Coffee roasting is so going on my list of summer projects! Now if I could step away from the internet long enough to get some actual work done.

  7. Very cool idea!! Definitely going to pick up a cheap popcorn popper somewhere and start roasting. This has made my coffee addiction so much more exciting.

  8. The fiance and I are completely addicted to coffee. We were both baristas for about two years, but more because we fracking love coffee than we needed the job. It has never even occurred to me that we could roast our own though!! This opens up a whole new world of possibilities. I can’t wait to try it.

  9. i have been roasting my own coffee beans at home for several years now…only i use a dedicated cast iron skillet and wooden spoon over our gas range. the process is basically the same, only you’re the one doing the stirring instead of the popcorn machine (they must be stirred CONSTANTLY). i only roast my beans during warmer months, due to the amount of smoke it produces (part of my roasting process involves taking the whole thing outside), and then stockpile them in the freezer for the winter months and grind the beans at the time of use.

    the main differences between using a cast iron skillet instead of the popcorn popper are:
    1. controlling the heat. it takes a batch or two to figure out the right amount of flame so that you get a nice roast without burning.
    2. at the point of the second crack, which is when the beans really begin to smoke, i take the entire skillet and beans off the heat, run outside, set the skillet on the sidewalk and continue stirring them as the pan cools. i find this gives me a great roast without filling the house with smoke (the cast iron pan cools slowly, so they’re still roasting even after i have removed them from the flame).

    for me, i really love the extra involvement of roasting them in the cast iron skillet…even though it is a bit more consuming, so that i have more control over the roasting process as a whole.

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