Posted in Kafevend Blog
Instant coffee isn't a recent invention. As far back as 1890, a New Zealander by the name of David Strang acquired a patent for "Strang's Patent Soluble Dry Coffee-powder". Another man from Belgium by the name of George Washington (no relation) invented another process a couple of decades later after moving to America. He founded a company in 1910 to begin mass producing his new product in New York. It met with success, particularly during WW1 when instant coffee was seen as a useful way to provide coffee rations to American soldiers.
One of the big players in instant coffee came along yet another twenty years down the line. After being approached by the Brazilian Coffee Institute, Nestlé began looking for ways to make a soluble coffee product to help deal with the surplus of coffee in the country. By 1938, their new instant coffee, known as Nescafe, began to be sold in Switzerland and later in London. As during WW1, the American military again bought up large stocks of instant coffee for their soldiers during WW2. It's commonly believed that the American soldiers in Britain preparing for D-Day helped to introduce instant coffee to the country.
It was also a war time invention that saw the next leap forward for instant coffee. Freeze drying was invented as a way of preserving blood serum as it travelled from America to Europe during WW2. As with many inventions with their origins in war, during the subsequent peace it was turned to more civilian applications. Freeze dried instant coffee is now one of the most common methods of production, alongside spray drying.
Both of these processes start out by using a coffee concentrate. Finely ground coffee is dissolved in hot water, essentially making lots of strong coffee. In spray drying, the concentrate is sprayed into a large cylindrical tower. As the tiny particles fall, they dry and are collected in a chamber at the bottom. Before being packed, the particles are made larger through either steam fusing or belt agglomeration (a big blob made of little blobs) to produce the granules we use.
Freeze drying is a more expensive method, but results in a higher quality coffee. Agglomerated wet coffee granules are rapidly frozen and then placed in a drying chamber. A vacuum is then created inside the chamber which lowers the temperature required for water to boil. This means that sublimation can occur, where the water can turn from a solid into a gas without passing through the liquid stage in between. Heat is applied, typically either through radiation or conduction to extract the ice from the coffee. Then a condenser inside the chamber collects the water vapour. Amazingly, this process can remove up to 99% of the water content in the coffee. Finally, the coffee is removed and packaged.
Although here in the West we might think of ourselves as moving on to enjoy more elaborate coffees, last year in the UK 77% of the coffee that we bought was still instant. Even if we were to give it up tomorrow however, instant coffee makers would still be able to sleep easy as countries like China, Russia and India are becoming big consumers of the stuff. So decriers beware, instant coffee is going nowhere fast!