How Water Temperature Affects Extraction

Coffee brewing is essentially an extraction process. Hot water passes through the coffee grounds and dissolves the flavour compounds that eventually end up in your cup.

Water temperature plays an important role because different compounds dissolve at different rates. Lower temperatures (between 79°C to 85°C) tend to highlight brighter, fruitier, more acidic flavours, while higher temperatures (between 90°C to 93°C) extract more chocolatey flavours, sweetness and body, while temperatures exceeding 96°C produce bitterness.

This is why most coffee is brewed within a relatively narrow range of around 90°C–96°C. Within this window, enough energy is available to extract the desirable flavours without pulling excessive bitterness from the coffee.

If the water is too hot, extraction becomes more aggressive and can produce harsh, bitter flavours. If the water is too cool, extraction may be incomplete, leaving the coffee tasting sour, thin or underdeveloped.

While grind size, brew ratio and time all affect extraction, water temperature remains one of the most important tools for influencing the balance of flavours in the final cup.

Cold brew is the notable exception. Rather than relying on heat, cold brew uses a much longer contact time—often 12 to 24 hours—to achieve extraction. This slower process generally produces a smoother, less acidic cup with lower perceived bitterness.