  Above 180° C, the beans begin to darken and the coffee's aroma grows stronger. The beans expand further and begin to pop. The surface of the beans begins to shine. As the beans continue to expand, their surface becomes smooth and their colour uniform. |
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| At 180-200° C the beans expand to three times their original circumference. |
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| At 210° C the cracking sounds can be heard again. The coffee beans' colour and aroma are changing every few seconds. |
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| At this point, the coffee roaster stops the roasting process at the temperature of his or her choice, and the roasted beans are taken to a cooling tank. |
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| At 278° C the coffee beans cease to give off smoke or water vapour. The surface of the beans becomes dull and black. The beans will not expand any further. |
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| At 300° C the surface of the beans turns black and sooty. The beans crumble at the slightest pressure. The aroma totally disappears. At this stage the beans have been completely over-roasted and carbonised. |
