I was called out by a customer of ours last week complaining that our coffee was tasting bitter and strong compared to what we usually supply. Of course all sorts of alarm bells ring. Are we roasting too dark, have we ground the coffee incorrectly?
In some ways I say thankfully it was none of the above! It turned out that the volume of coffee sales was relatively low and a kilo of pre-ground cafetiere coffee was hanging around for a couple of weeks prior to being used. The moment I opened the container I could tell that bad things were afoot.
For those of you who haven't had the pleasure of tasting or smelling stale coffee I can only describe it as the sensation of a coffee having died. Simply the reaction with the air has eliminated all the aromatics; as a result the taste is flat monotone and unpleasant.
The solution in this instance is for us to supply the coffee in smaller packs and smaller quantities. I had brought along a freshly ground pack of coffee of the same blend to compare and contrast. One coffee was alive, the other dead - beware the air!