How Should a Roaster Treat Decaffeinated Coffee?

There used to be a time when it was easy to roast decaffeinated coffee. Because the quality of coffee being decaffeinated was so poor, it did not matter how you roasted it but dark was preferred. After that, grinding it and putting it in a can hid it’s physical defects. To find a specialty coffee that was decaffeinated was very rare. In the last decade, more high-end coffee is being sent to decaffeination plants thereby producing higher quality specialty, decaffeinated coffee.
I am still not convinced there is a compelling reason to drink decaffeinated coffee. If your Dr. says you should switch to decaf, I suggest you switch doctors!  If you are still going to switch, then the least that us roasters can do is to provide you with the best decaf possible. This will require learning the best ways to treat decaf coffee in the roaster.
The considerations for roasting decaffeinated coffee are different from their conventional counterparts. As a roasting professional, you go through the same processes whether working with decaffeinated coffee or conventional coffee. While the fundamental processes are the same, the nuances and the results can be very different. For this article I have drawn from my own experiences as well as called on some of the industry’s professionals to describe some of the considerations for working with decaffeinated coffee.
Choosing the coffee
In the past, and still prevalent today, the lower grade coffees are sent to be decaffeinated. However, some great coffees are being sent to plants as well. Some roasters are even sending their own choices of coffees to be decaffeinated. With as little as a single container, a roaster can choose a coffee that holds up to the strain of the decaffeination process and continues to yield a flavorful cup. They can then send that to be processed as a decaf coffee. It tends to be the ‘high end’ or ‘acidic’ flavor notes such as orange, lemon and raspberry that get hurt the most and the softer flavors such as caramel and butter that do well. By selecting a coffee that starts high in body with medium to low acidity you will find that the flavor profile remains very stable.
I did one blind tasting of conventional vs. Swiss Water Process decaffeinated coffee from the same lot where I actually (by a ¼ point) preferred the decaf version of one the coffees. The coffee was a nice one to begin with, and I was genuinely impressed with the results.
If you are not sending your own coffee out, then you should ask for samples from the company doing the decaffeination so you can score it yourself before ordering. A mistake that is often made by novice green buyers is comparing the decaf coffee to the conventional coffee in your inventory. Remember, just because you have a Guatemala Huehuetenango on the shelf does not mean that the decaf version of the same growing area will have the same characteristics any more than two estates in the same area produce the same flavors. Rate the coffee on its own merits. If it presents well in the cup then it should be purchased. If it does not, then don’t! But don’t pass on it if it tastes different than your conventional version.
Roasting the Coffee
Decaf coffee acts differently than conventional coffee in the roaster. It should, therefore, be treated differently when developing profiles. Don’t assume that every decaffeination process has the same impact on the bean. The results are very different and need to be considered before roasting.
Jeff Chean of The Supreme Bean points out, “You can’t just monitor the bean temperature. It is going to crack at a different temp than the conventional coffee.” He also points out, “The second crack is softer so you really have to pay attention to the sound as well as the color.” Jeremy Raths of The Roastery gives those roasting decaf the following advice, “You need to sneak up on it with a smooth, low heat rise. Give it a long stretch between first and second crack.”
Both of the roasters above point out that a lower drop temp on decaf prevents tipping and allows you to develop the coffee more ‘gently’. The point being that careful attention placed on the profile can result in successful, flavorful cups. If you just roast it like your conventional coffee you will end up with scorched, bland decaf.
Single Origin or Blending?
I was always a supporter of blending decaf. This came from dealing with boring cup profiles that were better as a sum of the parts. It also protected me against lot changes, which can happen more often in decaf. Then one day I was presented with what the salesman called, “A single varietal, estate, specialty, decaf coffee.” Yeah right! And I have this high-speed rail project in Los Angeles that makes sense! But dang it! It WAS a good cup! I scored it an 83.5. I then had to rethink my ‘old ways’ and consider that good coffee in can equal good coffee out when it comes to decaf. I was then an advocate of single varietals in decaf.
A roaster should still blend for consistency on wholesale accounts, but don’t be afraid to stand up a single varietal decaf on its own.
The bottom line to this article is this: treat decaf as you would conventional coffee when it comes to selecting, cupping and blending. Treat it differently in the roaster and you can get an outstanding cup instead of, “Well, if the doctor said you HAD to drink decaf, then you can drink this.”