Soluble "Instant" Coffee


"Soluble coffee is ready in an instant, transportable, and has a long shelf life. No longer just a convenience item sitting on the kitchen shelf, it is now an ingredient in instant coffee beverages such as iced cappuccino and the flavored cappuccinos so popular in convenience stores. Many consumers use it by choice as a quick caffeine fix in the morning...
Doctor Sartori Kato, a Japanese chemist, made a soluble coffee in 1899 in Chicago to simplify the problem of making good coffee. It was not intended to compete with regular coffee on a quality or price basis. Kato's soluble coffee was first sold to the public at the Pan-American Exposition in 1901, and the first quantity order was received from Captain Baldwin and used on the Ziegler Arctic Expedition.
George Washington, born in Belgium of English parents, invented a soluble coffee in 1905. He got the idea as he was dining outside. His coffee was served in a silver pot, and as he was waiting for his wife to join him, he noticed that a brown powder had formed below the spout of the coffee pot. He tasted it, noticed the coffee flavor, and it gave him the idea of perfecting the process that would allow him to ship this brown powder all over the world, enabling people to make coffee in an instant.
Although the instant coffee did not have the same aroma, taste and body of brewed coffee, it had a marginal coffee taste, it was hot, and it provided caffeine. In 1910, Washington, by now an American citizen living in New York, came out with his G. Washington's Refined Coffee. In the summer of 1918, Washington's sales gained a tremendous boost with World War I, when the U.S. Army requisitioned his entire output. By October 1918 the army was calling for 37,000 pounds of instant coffee a day. Meanwhile, other coffee roasters created their own instant coffee. When the war ended in November 1918, the huge demand for instant coffee was abruptly eliminated and many producers of soluble coffee were driven out of the business, but veterans who had become accustomed to the taste created a market for soluble coffee.
While World War I produced a generation of veterans accustomed to the taste of soluble coffee, World War II broadened the acceptance of this convenient coffee. The United States Army Quartermaster Corps, in the period from 1942 to 1945, bought more than 257,000,000 pounds of coffee concentrates. Soluble's light weight and compactness proved ideal for rations. Millions of Americans in the armed forces became acquainted with the soluble during the war years.
The development of soluble coffee was and is attributed to the convenience. Although the taste and aroma is no comparison with high quality brewed coffee, it does not have to be roasted and ground, then extracted, and doesn't easily stale. It does have a brown color, contains caffeine, and is convenient.

The Process

To make soluble coffee, green coffee is roasted and ground. It is then put into percolators, not unlike ones used in restaurants. The liquid coffee then goes into the evaporator to be concentrated into a thick liquor. At this stage, the extract is a heavily concentrated syrup and is ready to be converted into powder. This is accomplished through heat applied in a vacuum drier. This type of drying is also called spray drying because the coffee extract is sprayed onto the drying drum where applied heat and vacuum reduce the extract to a powder.
Until the mid-sixties, spray-drying was the most commonly used method of drying coffee extracts, but in 1965 the first freeze-dried coffees appeared on the market and were distinguished by their higher quality.
To process this, the coffee concentrate is placed into a chamber which has a high pressure vacuum and the moisture is frozen off. The result is sold as a powder, which looks like a coarsely ground coffee and is considered to be more coffee- like in taste. It is a very expensive process and the stray-dried manufacturers, in an attempt to retrain their market, responded in 1967 with a process of agglomerating instant coffee powder into a granular product, which looked more like real coffee grounds.
The use of high temperatures in the extraction process of soluble coffees puts certain demands on the green coffees beans not present when extracting traditional coffee brews. The Canephora species (Robusta and Canilon) has the advantage of providing a higher content of solubles and caffeine. They are therefore preferred for the production of powder coffee."

-pp. 49-50, Soluble Coffee: Over a Century of Convenience by Shea Sturdivant Terracin in Tea and Coffee Trade Journal, Volume 173; Number 4 (April 20, 2001)

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