Consistency In Home Coffee


That’s a bird seed scoop–$3 at PetSmart that serves as my ground coffee receptacle every morning. I had been looking for a funnel or just some cleaner way of transferring coffee from a container to the glass beaker. You slide that guillotine-like hatch with your thumb and the grounds–mostly without fines–slide right out with a few taps into the center of the beaker bottom. A few shakes evens it out and now the unit can be placed on a scale. I weigh the beans and water. I use a 1:15.5 ratio, so 37 grams of beans get 574 grams of water. This comes to two diner-size cups of coffee. The Grindmaster 495 is in the basement. This 1996-vintage behemoth makes a racket, and frankly I enjoy the walk upstairs taking in the aromas of the freshly-ground beans while the water is just about to boil. It’s part of the experience. I outlined the advantages I have with home roasting versus the specialty coffee roaster/retailer in a previous post but neglected to go in-depth on consistency as it relates to brewing and roasting. On brewing, I trust I’ve shown that I can exactly replicate the formula on a daily basis. Your local pourover purveyor cannot. But, I’ll give her that. Let’s assume that she is getting her formula right, every time. Ponder that the next time she’s swirling water around with the gooseneck kettle. This leads us to the consistency of roasting. There they have me beat. With an expensive drum or some type of hybrid air/drum system they can tinker endlessly and go through kilos of coffee, cupping it to find the ideal roast for a particular varietal, changing drying times or air flow introductions to create a “profile” for that coffee. Want it more juicy? Shorten the drying stage. Want the brightness more mid-palate than upfront? Hit it with air sooner. These are crude simplifications but are the sorts of things roasters do. They can dial in a roast and program it. That I can’t do. I alluded previously to the fact that in some ways this is another advantage I enjoy: I get to try coffees myself at different roast levels, featuring various characteristics, without burning through all my coffee in the process. But the real secret is that I have no “profiles” for my coffees, or, I just have one. I roast the same way every time! I should admit that I am loathe to change things that are working, and I probably should experiment more, but after doing this a while and learning that drum profiling just does not translate to hot air popper roasting I found my coffee consistently better when I followed some guidelines. My poppers are not modded. I am not a handyman nor am I good with circuits and electricity. Forget it. It took me months to get up the gumption to simply try roasting this way. What helps are the soup can chimney and a digital thermoprobe affixed to the chimney with high-temperature tape. The probe end angles in from the bottom of the chimney into the roast chamber. The readings help me understand where I am in the roast, along with the use of other senses such as sight, (color of the beans), smell, (changes from grassy to sweet to ashen, if you go that far), and sound, (the onset of the first pops, etc.) In order to guarantee that there’s a chance I will like the end product I make sure to do these things: Chris Schooley of Sweet Maria’s has found that if drying stages are extended especially on high altitude cultivars sweetness can be intensified. This means I do pauses. I turn off the popper for 20 seconds at 40 seconds in and at 1:40 in. When I resume I am watching to hit 400 degrees F while monitoring a timer and the beans. Carl Staub of the SCAA has the science on something called the Best Reaction Ratio. In brief: “The best cup characteristics are produced when the ratio of the degradation of trigonelline to the derivation of nicotinic acid remains linear…Monitoring the bean temperature offers a good method of approximating the reaction distribution during this phase of the roasting. The ideal environmental temperature, ET, for best reaction ratio, BRR, is from -400-424 degrees F…” (SCAA Roast Color Classification System developed by Agtron-SCAA 1995). I don’t have the bean temperature but I do have the ET readings. So I endeavor to hang around a little bit between 405-430 degrees. Through trial and error I have learned how to stay in that zone without unnecessarily delaying the onset of a vigorous first crack. It’s a blunderbuss method, but I use a table fan. If the temperature is rising too fast I can direct blowing air in there, which stabilizes or temporarily drops the temperature slightly. I make sure that I don’t leave that zone too fast or prematurely. You want a vigorous start of first crack. You don’t want to sputter in-or-out of the first crack. Simultaneously, you don’t want to rush through the crack. Here the fan can be used again, sparingly. I determine a hot, on-the-fly end of the first crack. From previous roasts I’ve pre-set how long I will go after the crack is finished. (Always do a roast log). The fan is used at the end for a 20-second burst. ET in air roasters is supposed to be flat at finish, with bean temperature slightly ramping up to meet it near the end of the roast. I have done this with low-grown Brazils to high-grown Guats and Ethiopias. Of course there are surprises. Every roast is different. I had some trouble with two Rwandas–they were both Bourbon; I got them at different times. The Rwanda Kanzu Bourbon had to be stopped no more than 25 seconds post-first crack to salvage a sweet City +. If I stopped there on Rwanda Tumba Cocatu I’d have a City roast and so many quakers I’d barely get a day out of it. I almost gave up on Cocatu, until I went one minute past first crack. Reps, baby. I had it this morning–juicy, complex, then creamy. Love my Cocatu! It’s like tasting the difference between color- and black-and-white television. Your intrepid reporter gave them another shot, just before setting this down. Man, it was good, a light-roasted Kenya. I gotta give it up to them. But it was monochromatic compared to the technicolor hues I experienced earlier today. The rugged car commercials always say “Professional driver–closed course–do not attempt”. This is one area where I went and tried it myself, and the results are better than adequate. I guess I’m lucky to be roasting for only one. That doesn’t sound right! Oh, well. I hope to meet the girl with the demitasse tattoo. I don’t like tattoos…


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