Instant coffee can be made using different drying processes, with spray drying and freeze drying being two of the most widely used. Both methods remove water from brewed coffee extract to create soluble coffee, but they do this in different ways.
What is spray-dried coffee?
With spray drying, concentrated coffee extract is sprayed into hot air. The moisture evaporates quickly, leaving behind dried coffee particles.
The process is efficient and widely used in instant coffee production. Depending on the product and any further processing, spray-dried coffee can have a fine powder or granulated appearance.
What is freeze-dried coffee?
Freeze drying takes a different approach. The concentrated coffee extract is frozen and then placed under reduced pressure. The ice is removed through sublimation, changing directly from a solid to a vapour and leaving behind dried coffee granules.
Freeze-dried coffee typically has a larger, more irregular appearance. The lower-temperature drying process can also help retain more of the coffee’s aroma and flavour characteristics.
What are the key differences?
The main difference is how the water is removed from the coffee extract. Spray drying uses hot air and is a highly efficient process, while freeze drying uses freezing and reduced pressure.
This can affect the appearance and characteristics of the finished coffee. Freeze-dried coffee is often recognised by its larger granules, while spray-dried coffee is generally finer, although spray-dried coffee can also be further processed into granules.
Neither method is automatically the right choice for every product. The best option depends on factors such as the desired coffee profile, application, product specification and commercial requirements.
Understanding the differences between the two processes can help when selecting the right instant coffee for a particular product.