Oily vs Dry Coffee Beans

[elion_84]

I buy my coffee beans either from a local roaster or from a gourmet shop that sells private branded pre-packaged beans. The beans from the local coffee roaster shop are very oily. Once I'm done with the 1/2 lb batch, the container where I store them is slick and oily on the inside. When grinding these beans, my grinder has oil streaks, and the ground coffee tends to stick to the sides a bit. I find that I need to use much coarser grind with this coffee or my machine (Capress EspressoPRO Model #112) can't push water through.

On the other hand, the coffee from the gourmet shop is not nearly as oily compared to the other beans. I can use fine grind (1.5/2 setting on my grinder) and get somewhat better crema.

How oily should the coffee bean be? Does this vary with bean variety or freshness of the roast? Does it make a difference?

Edited April 1, 2004 by elion_84 (log)

[MGLloyd]

The degree of exterior oiliness on a coffee bean has to do with two things: the degree of roast (most important) and how long ago it was roasted.

In brief, the darker the coffee is roasted, the more oil is on the exterior. After a coffee is roasted very dark, oil will continue to migrate to the surface over a period of time. So if you have very oily coffee, it was probably roasted to a dark roast a few days ago.

[phaelon56]

Back when I just bought two pound bags of arabica French Roast at the local wholesale club and froze it, pulling out a bit at a time as needed. I thought that coffee had to have a bit of oil on the surface in order to have a good rich flavor. Not the case. Careful bean selection and roasting can indeed produce phenomenal results from beans that have no evidence of surface ooil. I've also on occasion picked up a half pound or so from a roaster when visiting friends and found it to be flat tasting despite an abundance of oil. MGLloyd makes a good point - it was probably roasted very dark and also sat for more than a few days.

I'm now finding that beans rpasted t the point where they hahve just a hint of oil on the surface here and there are usualy to my liking - lots of oil and it either has a slight burnt taste from overroasting or is just plain flat and stale.