This week, our special guest was Rob Hoos, owner of Hoos Coffee Consulting, director of coffee for Nossa Familia Coffee, and author of Modulating the Flavor Profile of Coffee. For this round of RoastID, we decided to shift our attention to the intricacies of the coffee roasting process, by focusing in on the various roasting stages, the importance of time-temperature and roasting conditions, and a selection of lesser discussed roasting variables such as airflow and drum speed. Some of the topics we touched on were final cup quality, sweetness, final nature of the carbohydrates, acids, proteins, and volatile aromatic compounds present in the roasted bean.
RoastID - See the Curve, Match the Curve is 3-week online challenge of roast curves and cup quality knowledge! Sort of like matching a cupped coffee to the correct roast curve, except, you never cup the coffee. Competitors enter an online quiz portal where we present some roast curves, and then try to match them to the correct cupping forms. This competition is more than a competition, but an educational opportunity to learn from roasting experts about how roasting techniques and decisions (and the changes in the roast curve) influence the taste of the coffee. Make sure to participate in the final round, on May 27th at 12 am PDT.
We understand that you may not have time to follow the entire session so we've added some handy quick links to key topics here. You can watch the video on our site, or click the links to be taken to that particular topic (this will take you to YouTube).
00:02:45 Round 1 recap
00:05:14 Round 2 topics
00:07:54 Defining roasting stages: drying, maillard/ yellowing, development, turning point
00:13:07 This first curve resulted with a wobbly RoR and long maillard reaction phase. Check out Rob Hoos evaluation for this roast.
00:20:07 Differences in curves and ROR readings amongst machines and probes
00:32:57 This second curve resulted in a short development time ratio, Learn more To learn why and how to roast to avoid an under roasted curve, check out Rob Hoos analysis and proposed techniques.
00:35:11 The third curve resulted in a long development time ratio and a short maillard period. Check out Rob Hoos evaluation of the curve.
00:40:14 The fourth curve had a slightly higher start temperature and also a shorter time overall. Learn more about how Rob Hoos evaluated this lowe max rate of rise with a higher turn curve.
00:44:04 This curve had a lower starting temperature and a lower turning point. Check out the full analysis by Rob Hoos.