title_body: Instant coffee has less caffeine than percolated and filter drip?
upvoted_answer: With instant coffee, you are not "practically eating the beans;" you are drinking reconstituted dried coffee.
  
  To create instant coffee granules, the manufacturer first brews the coffee using conventional methods and then either freeze-dries or spray-dries the coffee to create a soluble powder form. Dried coffee.
  
  The amount of caffeine in the instant coffee will depend largely the original brewing process. Since commercial instant coffee is created in very large volumes, they are likely extracting coffee faster than our meticulous home-brewed methods. So while caffeine is water soluble, it takes more time for the caffeine to be extracted and absorbed in the water than other compounds. And "more time" is not something that the mass-produced instant process allows. Less extraction time = less caffeine.