thedarkness wrote:I believe my coffee was partly to blame, I suppose it just wasn't that fresh any more, even though just a week out of the bag.

The only time parameter in terms of coffee age is the roast date. If the coffee bag is not marked with the "Roasted On" date then the educated assumption should be that it is stale when the bag is opened.

Coffee is a drink of layers which is why many people swirl the cup before drinking. I have a cup with demi spoons in it on my cup warmer. I just grab a spoon, give it a quick 3 or so stirs to mix the layers up for a more balanced up.

Randy G. wrote:The only time parameter in terms of coffee age is the roast date. If the coffee bag is not marked with the "Roasted On" date then the educated assumption should be that it is stale when the bag is opened.

I've never bought a bag more than 2 weeks away from roasting. Unfortunately I haven't been able to find fresher, but how do you guys feel about the fact that its in a sealed bag immediately after roasting? Obviously it will eventually go stale, but the bag must be able to hold up for a few weeks prior to opening?

A while back there was a chemistry department party at my University. I brought two lever espresso machines and spent the whole time making espresso. Anyway one of our graduate students was evaluating the procedure, and said, "You really are just doing a column chromatography when you make espresso."

He was absolutely correct. When hot water passes through the coffee plug materials that are removed from the coffee go into solution and then often re absorb onto deeper layers of the plug. They continually dissolve and reabsorb until they get through the plug. The materials that stay dissolved most of the time come out the bottom first. The materials that bind most strongly to the coffee grounds are eluted much later. This results in a serious flavour gradient. Many of the bitter components of coffee elute quite late, so the top of a cup of espresso tends to be more bitter than the bottom. The least polar molecules tend to elute early.

The goal of espresso making, really is to get rid of some of the nasty tasting stuff that elutes very slowly.