In this phase the beans go through a metamorphosis: they change colour, decrease in weight, increase in volume, lose moisture and, above all, acquire aroma.
- At 100°C they turn a golden colour and the roasting fragrance starts to be released
- Over 150–180°C they become larger, shiny and brown
- At 200–230°C the roasting reaches its optimum level and the coffee gains its distinctive scent.