The coffee beans are roasted to taste and then finely ground into an almost powder-like form. Then, they’re stripped of their water content through brewing, leaving behind an extract.
The dehydration process leads into a scientific drying process, to put it mildly, usually conducted by freezing or spraying with liquid coffee concentrate in a very hot environment or by the more sophisticated methods include agglomeration and aromatization which result in a final product which is readily soluble and has an odor and flavor more nearly that of freshly ground coffee.
The technical procedures of freeze-drying for instant coffee include: baking coffee bean, extraction, concentration of extracted liquid, freezing concentrated solution, sublimation drying, desorption drying, smash, and package. This results in crystallized coffee grounds.
Soluble coffee, which is now universally accepted as a ready means of making a most acceptable beverage. One cup of instant coffee, containing one teaspoon of powder, may contain 30–90 mg of caffeine, while one cup of regular (filter) coffee contains 70–140 mg.
Due to the dehydration process, instant coffee simply doesn’t retain the same amount of caffeine as ground coffee does.
What is instant coffee?
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