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When I saw this "Coffee Roasting Defects Pictorial" in home-barista and saw the hunter's delight, I kept it. Although you have to drink the coffee, you can find out a lot of problems by looking at it, and there is no conflict in logic.
Derived from the discussion of "Home Roasting Competition" (the object is washed beans)
Quaker: uncooked beans
Quaker
Charring: surface overheated scorch
Charring
Tipping: another kind of surface overheating or drum speed is too slow.
Tipping
Center line charring: excessive firepower caused by scorching and dehydration on the centerline before the explosion
Center line charring
Crater: crater (crater), caused by excessive firepower between the first explosion and the second explosion
Crater
Under roasting: not enough baking, just into a burst, beans flat and semicircular noodles into 90 degrees, used to test OK cup, not suitable for daily drinking
Under roasting
More dinkable roast: the explosion is completed, the centerline is slightly bulged on both sides, and the bean body is well expanded.
More dinkable roast
Bean expansion after 1st crack: after the explosion, the bean expanded and cracked, the centerline was not charred, and the silver skin in the seam could be clearly seen.
Bean expansion after 1st crack
Note: the center line will turn black before the second explosion, which can be used as a basis for judging the end of the first explosion and before the second explosion.
