Shane – there is, of course, a 1″ gap at the bottom edge of the big BBQ lid in the back, so it can open. I’ve thought about trying to block that off to keep more heat inside. Do you think that would keep too much smoke inside, negatively affecting the profile of the bean?
As to whether or not it affects the profile of the bean, I do believe that it can lead to a slightly smoky odor to the beans, only detectable if left in the open air for days at a time, never having sealed up the beans after the roast. I note a slight ashy/smoky odor to the beans. However, I do not think that this is detectable to anyone but the upper echelon of coffee cuppers worldwide and certainly not detectable to Joe coffee drinker/average person. I personally cannot detect it in the aroma or cup if the beans have been covered, I do believe this smoky odor under those conditions is produced by not venting the grill enough; however, I do feel that the net gain (60% reduction in roasting costs) is worth it all things considered. Hope that helps! I recommend it for businesses. If you are not at all concerned with the cost of the roast and only pursuing perfection, then you may wish to forego the blocking.
I’ve incidentally heard lately an increasing desire for food fired, mesquite smoked coffee, as well as other types of open fire roasted coffee. Not sure if this is an indication that smoky coffee maybe sometimes even desirable.
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