I'm a bit late to the party on this, but I thought I'd throw my $0.02 in the mix. This topic got me thinking on Sunday evening about preground coffee; After talking it over with Doug Zell yesterday, we both were in firm agreement.

disclaimer: I'm talking entirely about drip and filter coffee here. We're all in agreement that for espresso you should have a well-maintained burr grinder designed for espresso.

You all got me curious, and after some investigation through google analytics, accounting reports and personal anecdotes from customer service guys and production, we estimated that preground coffee only accounts for 20 - 25% of our web sales, which is pleasantly surprising to me. I was thinking it was more around 30%. To me, this says that coffee consumers are becoming more aware of the benefits of having their own grinder.

That being said, both Zell and I agreed that having preground from a calibrated, maintained, commercial burr grinder is far superior to a whirly blade/mortar & pestle/bottom of a pan on the counter any day of the week. I'd rather get a brew from grounds that are evenly and consistently sized, rather than the boulders and fines produced by a blade or extremely low end burr grinder. Blade grinders will 100% of the time produce a brew that is both under and overextracted at the same time.

Even coffee ground a week out on a commercial grinder like the ones we have here at the roasting works will produce an acceptable to better-than-acceptable cup if it has been stored properly in an airtight container away from light and heat. I've been more than surprised a few times at the level of quality I can get from a chemex (or even FP) when going to my in-laws for extended visits. Most of the time I'll grind and bring the ground coffee with me for the trip. Once, I brought my Kitchen-Aid with me....I don't think i'll do that again. Even at 4-5 days out, I could produce a cup that was enjoyable with nuance and subtlety.

I still endorse anyone getting into coffee having a dedicated burr grinder in their home. It doesn't have to be that expensive. The Capresso Infinity ($100-ish) is a good grinder for the money if you're on a budget.

sweaner wrote:When I go on a Boy Scout camp out, I do bring pre-ground coffee. ....

Take a look at REI or similar backpacking stores as there are small hand grinders available. With the smell of fresh-ground first thing in the AM, you should be able to get all your PK duties easily covered.. Also, the Aeropress would be my choice over a press. I talked to Allen (the inventor) about it- I told him that it would be cool to have a portable model... the plunger could have a cap to enable the storage of beans in its void, and that the base of the outer section should be detachable for easier carrying in a pack.

HB wrote:Along these same lines, Abe/Jim's report in Experiments with Preground Coffee for Espresso and a Brew Pot provides some interesting food for thought (e.g., "The brewed coffee experiment has been repeated by others, and I hear they all came to the same result: pre-ground was better. The espresso on the other hand is very intriguing, and I think it is coffee dependent.").

Seems the experiment in the link may contradict some assertions in this thread (for brewed). Perhaps it is a matter of the extent of "staling" or what one means by "preground", but it certainly does not seem clear cut.

With respect to espresso, I have tried the ten minute pre-grind on really fresh coffee with pretty positive results. I generally just try to space out the coffees, but this has me thinking a bit about the real benefits of resting.

That ground coffee becomes unacceptable for espresso in minutes and for brewing in hours was a mantra on alt.coffee (usually followed by "get a grinder, newbie"). It is clearly false.

First off, it makes no sense. If some espresso is best aged for a week whole bean, and some brewed coffees aged for a few days, it's not going to stale in seconds once ground. Clearly, there has to be a tradeoff of aging coffee whole bean and aging it ground. For instance, if an espresso blend is best a week after roasting, can you do as well waiting two hours with it ground on the day of roast? I can;t see why it wouldn't work. Second, not just Abe and I, but lots of people have observed improvements in some coffees both for espresso and for brewing after letting it sit ground for some time.

But I don't think this is the whole story. Start with a caricature: a fermented, rioey natural Brazil from a hundred years ago. Good practice was to let the greens sit a year or two, then roast it about an hour, then let it sit ground for a day or two. Each aging step made it better. But the improvement was from reprehensible to drinkable. As I say, this is a caricature; but my question is this: Suppose aging is about removing the flaws in a coffee faster than good flavors. Then it may make sense to let most coffees age a bit; but it doesn't make sense to do this for the very best coffees.

Suffice it to say, I'm not letting any Esmeralda sit around ground.