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Instant coffee was launched onto the market in the 1950's. A cup of instant coffee can
be prepared quickly and easily, without brewing, since this has already been done in the
factory.
To produce instant coffee, millions of cups of coffee a day are produced. These huge
amounts of fresh coffee are then concentrated by allowing a considerable amount of the
water to evaporate. The coffee produced is then made into instant coffee using one of the
two techniques: freeze-drying or spray-drying.
Freeze-drying
During freeze-drying the coffee concentrate is deep-frozen to a temperature of
around -40 degrees Celsius, causing the water particles in the concentrated coffee to form
ice crystals. Using a method known as sublimation the ice is extracted from the frozen
granules. The result is freeze-dried granular coffee with a noticeable, yet limited loss
of flavour.
Spray-drying
During spray-drying the concentrated coffee is sprayed into the top of a high
tower together with hot air. Due to the heat the water evaporates as it falls, so that all
that remains is dried powdered coffee. Spray-drying is simpler than freeze-drying. Because
high temperatures are needed for this process, many of the natural properties of the
coffee are lost.
source: Douwe Egberts |
