Cool Those Beans
May 30, 2005
Over on INeedCoffee, James Cameron writes about the need to rapidly cool coffee beans as soon as they’re done roasting.
The number one problem in producing great coffee roasted at home is the failure to cool the roast quickly after roasting. Coffee is √¢‚Ç¨¬ùroasted√¢‚Ç¨¬ù rather than √¢‚Ç¨≈ìbaked√¢‚Ç¨¬ù and for good reason. When roasted properly at high heat quickly allowing convection between the heat source and beans as well as from bean to bean you will avoid √¢‚Ç¨≈ìbaking√¢‚Ç¨¬ù your beans. The baking of coffee beans renders them flat and void of the brightness and zip they should have. Baking occurs when the beans are roasted too slowly or allowed to remain in a slowly decelerating heated situation. When this happens the coffee is losing the zip it has at peak of roast.
The manufactured home roasters that I have seen or heard of all have the same problem; they lack a good cooling system. It is virtually impossible to cool your roast quickly enough in the same chamber that they were, moments ago, roasting in. We in the industry uses sample roasters which are all outfitted with a separate cooling pan built to cool the roast as quickly as possible. We watch the roast checking it with a small scoop we insert into the roasting chamber about every 15 seconds when the roast is nearing the profile we desire. When the roast hits the desired profile we immediately dump it into a cool and operating cooling pan and generally stir it to speed the cooling along further.
James goes on to give some great simple ideas for constructing your own efficient home roast cooler.
My iRoast immediately shifts into a cooling mode as soon as it’s done roasting, turning the fan up on high and pumping room temperature air into the roasting chamber for about four minutes, but James is probably right — the residual heat in the chamber has a lot of thermal inertia, and a lot of that chill is being sunk into cooling the chamber instead of the beans.
I may have to give one or two of these cooling ideas a try. The only downside is that it’s going to take some careful handling with oven mitts to open the iRoast chamber before it’s done cooling — that puppy gets HOT.