title_body: Waiting a few minutes or adding a little cold water immediately, do they make different tastes for instant coffee?
upvoted_answer: It is my understanding that the bitterness comes from coffee grinds in hot water for longer period of time or in really hot water above like 160f. The longer they are in hot water the more bitter it becomes.
  
  So I would assume that leaving them in the hot water til it cools would have a more bitter taste, however I'm not clear on instant coffee, or how long it needs to steep. In fact it may be designed to work the way you use it.