Chances are if you are reading this coffee site you really don't care about instant coffee. To me, it feels like an abomination of the real stuff; almost a swear word. However, there are people who drink instant coffee and in my experience it's mostly the English. Sure, it's a quick way to make a single cup of coffee, but now there are the coffee pod machines, which will give you a great single cup of coffee in less time than it takes to boil the kettle. That said, if you are reading this section you want to know what instant coffee really is…
Instant coffee is a dehydrated coffee. It is either made into granules, liquid form or powder through many different manufacturing processes. Re-hydration occurs when the instant coffee mixes with boiling water.
Instant coffee was invented in the early 1900s by a Japanese scientist living in Chicago, Sartori Kato. It began to be marketed commercially in the 1930s by Nescafe. Its simplicity, cost and long shelf life made it a popular product in WWII.
Then there are 2 drying methods for the extracted concentrate. Freeze drying and spray drying.
Freeze drying is the removal of water by sublimation. The coffee is frozen, is put on a metal drying rack and a vacuum is created in the chamber of the drying rack. The coffee is then warmed using radiation or conduction. Condensation occurs and the frozen granules expand and the water vapor is removed. Finally, the granules are packaged.
Spray Drying is a cheaper method for instant coffee producers. However, the coffee particles may be too small for the general consumer. Nozzle atomizers spray water and high speed rotating wheels are used to process the beans.
A benefit to using instant coffee is that you can regulate the strength of the coffee.