3- Surface area and excitement :
For water and coffee to react, there must be contact between them. This contact varies depending on the surface area. The finer the coffee grind, the greater the surface area, resulting in a higher surface area-to-volume ratio. Conversely, smaller particles allow for a higher percentage of dissolved substances to be extracted.
Therefore, the grinding process is crucial in coffee production. It's also essential that all coffee grounds are of a uniform size for even extraction. If they aren't, larger particles will extract fewer dissolved substances than smaller ones, resulting in uneven extraction. This will produce a mixture of highly dissolved and poorly dissolved substances in the same cup of coffee, leading to an unsatisfactory result and taste.
