How is Freeze Dried Coffee Made
Coffee is one of the most popular drinks worldwide, according to the British Coffee Association around two billion cups are consumed every day. Instant coffee accounts for more than 34 percent of all the retail brewed coffee consumed around the world.
Here is a little bit of history: David Strang of Invercargill, New Zealand invented and patented instant or soluble coffee in 1890. For its manufacturing it used something called "Dry Hot-Air" process. The first successful method of creating a stable soluble coffee powder was invented by Japanese American chemist Satori Kato of Chicago in 1901. Around 1930, Nestlé and the Brazilian Coffee Institute jointly developed an instant coffee, which then became popular during the Second World War. From then on, its popularity only grew. In the 1960s, freeze-drying was introduced to improve the quality and flavor of instant coffee.
Colombia started producing freeze-dried coffee in 1974 that the National Coffee Federation implemented this process in Chinchina a small town strategically located in the middle of Colombian Coffee Triangle to give added value to the Colombian Coffee and open other markets around the world.
Freeze dried coffee has higher quality and better taste due to the flavor preserving process, while instant coffee powder can taste more burnt. The freeze-dried coffee combines the best of 2 worlds, great coffee aroma and flavor and easy and fast preparation and a long shelf life, up to 30 months preserving all the great qualities of a fresh coffee.
But how is freeze dried coffee made? Roasted and Ground coffee is submitted to the processes of extraction, concentration, freezing and vacuum to obtain a freeze-dried coffee.
In the extraction process, the roasted and ground coffee goes into extraction columns and then hot water goes through the columns to extract the soluble solids of coffee, or coffee beverage. This coffee beverage must be concentrated at least up to 40% to facilitate the following processes.
The concentration process is done by freezing the coffee beverage up to the freezing point of the water that is zero Celsius, so only water becomes ice, and it is separated from the coffee extract by density; at this point the coffee extract it is now concentrated, and thanks to the low temperatures that it is submitted to, it preserves all the natural aromas and flavors of a fresh roasted and ground coffee.
The concentrated extract is now ready for the freezing process, it is done on freezing bands at -50 Celsius to obtain a specific thickness that will help speed the freezing and the final grinding of the coffee in the freezing room.
The grinded frozen coffee extract is placed in trays that go into a vacuum tunnel where the rest of the water that is in solid state (ice) is extracted as steam, leaving just the freeze-dried coffee ready to pack.
It is important to notice that the freeze-dried coffee is highly hygroscopic, that is, it absorbs humidity from the environment fast, so it must be storage adequately and it cannot be left open as it deteriorates.
Why do consumer in Australia, UK, China, Russia and other countries do prefer the instant soluble coffee? as they say, freeze dried coffee preserve most to the aroma and flavor of a roasted and ground coffee and it is easy and fast to prepare and enjoy.
By Raul Valencia
