title_body: Aeropress: at what stage does most of extraction happen?
upvoted_answer: Generally, the &quot;extraction&quot; happens when the coffee is in contact with the water. So from the initial point of contact in this case the bloom phase pour till all the water (with dissolved solids) is removed from contact with the grounds.
  Technically speaking, The initial small quantity pour and stirring in your recipe is the bloom phase and the second pour, stir and press would be the main extraction phase. In the case of your recipe, most of your extraction would happen during the second wait phase &quot;Wait time (usually 1 minute)&quot;, followed by the second stir phase.
  The first bloom phase is usually to let the coffee expunge as much CO2 as possible that's trapped from the roasting process. The CO2, when dissolved can make the coffee more acidic/bitter, hence the blooming phase in your recipe to mitigate that. There is also some extraction during this phase but is rather dwarfed in comparison to the main extraction phase.