The differences here don't stop at the roasting stage. Any changes you make during the preparation process influence the milligrams of caffeine that end up in your cup of coffee. Grind size, how you prepare the coffee grounds, and your method of brewing matter for the final tally. We've touched on this at great length in other sections, but think about the various ways you can prepare coffee. These different types of coffee matter. Brewed coffee, drip coffee, pour over coffee, cold brew coffee, French press, using a plunger with your AeroPress - it all makes its mark on the final prouct.