title_body: Can flavoured coffees alter the shelf life of the coffee?
upvoted_answer: You are quite right - the flavouring does indeed change the shelf life in a certain way. It is necessary to look at this from two perspectives.
  
  Shelf Life by Safe Consumption:
  
  The flavouring compounds used to flavour coffees last longer without degrading. This means that they ARE NOT the limiting factor when it comes to the shelf life of a coffee. Therefore, shelf life is not changed by flavouring the coffee as these compounds degrade (or go bad) after the coffee itself.
  
  Shelf Life by Taste:
  
  Because the coffee has been treated with flavouring compounds, it will hide certain aspects of degradation of the coffee due to aging, decaffeination, and oxidation. 
  
  
    In addition, these flavors help extend the shelf life of coffee by
    disguising changes in flavor due to decaffeination, oxidation, or
    aging processes.
    
    Source: How Products are Made
  
  
  Therefore, shelf life by taste is changed, as the flavouring compounds mask the degradation and therefore the bad tastes of the aging coffee.