How instant coffee is made

Grind the roasted beans

Coffee that has been roasted in a rotating drum is cooled and ground to the size of coarse sand, so water can reach the whole bean.

0.5 to 1.1 millimetres

Brew it by the tonne

Industrial percolators push hot water through banks of ground coffee. Water runs at high temperature and under pressure, which frees larger carbohydrates from the bean that help the powder dry later. The spent grounds weigh about twice as much as the soluble coffee made, and can be burned for heat.

up to 175 °C

Boil off the water

The thin extract is concentrated in evaporators until it is a thick, dark syrup. Aroma compounds are captured along the way so they can go back in later.

Freeze it and mill it

For freeze-dried instant, the extract is frozen quickly so only small ice crystals form. The frozen slab is milled into granules and sifted for an even size.

Vacuum away the ice

In a vacuum chamber the ice sublimates, turning directly to vapor without melting. The dry granules are left behind and expand to many times their frozen volume.

granules swell tenfold

Spray into hot air

In the cheaper spray-dry route, the concentrate is atomized into a tower of hot air through a nozzle or a wheel spinning at about 20,000 rpm. Each droplet dries in seconds and falls as a fine, dust-sized particle.

5 to 30 seconds

Fuse into granules

Spray-dried dust is too fine to use, so steam sticks the particles together into larger granules. Aroma recovered earlier is added back before jars are filled.