A few months ago I visited Alana's Cafe in Redwood City, which advertises its "gourmet coffee." They get their own blend of Mountanos Brothers, and they prepare a drip brew that tastes like a fragrant, fresh, medium roasted Guatemalan. They sell this coffee in bags but I learned they only get it pre-ground, so I didn't buy any to take home. I wondered, though, why it tasted so good. What about Babbie's Rule of Fifteens, which says that coffee brewed 15 minutes after grinding is stale? I wondered if this is the case when a pound or more of coffee is sealed in a bag where there's no place for the aromatic flavors to escape? Then I came across this discussion today in a current thread about Blue Bottle Coffee:
Intrepid510 wrote:Has anyone ever had a good experience at one of their Farmer Market locations? Obviously I haven't and I really should know better. Went to their stall at the Marin Farmer's on Sunday, just awful, would've gone back to ask for a refund had I not had my children with me. Preground coffee coming out of their bags without a grinder in sight, tasted stale to me like it was ground early in the AM.
With their apparent commitment to quality at their stalls that I have experienced it looks like they are going to give Starbucks a run for their money with their current influx of cash...
Nick's post was followed by a reference to an old thread where Abe Carimali, Jim Schulman and others took a lead from Scott Rao and found in some cases that pre-ground coffee, especially if it's fresh, can taste better. What follows is a comparison of pre-ground fresh coffee, pre-ground coffee that's already been rested in whole bean form, and espresso versus a brew pot. Some posters suggested that aging of whole beans is comparable but slower than pre-grinding fresher beans. Several reported that espresso extraction was more sensitive to pre-grinding than immersion brew. Here's that thread:
Experiments with Preground Coffee for Espresso and a Brew Pot
All of this leads me to think more flexibly about aging and pre-grinding. Perhaps I can buy a bag of fresh-roasted, pre-ground Mountanos Brothers coffee at Alana's and it will still be fine for drip, especially if I quickly freeze it airtight. Maybe I can get an earlier taste of home-roasted beans if I grind and let them rest awhile to round out and integrate the flavors up to 12 hours. Perhaps I can even pull some espresso of fresh home roast, especially if I grind coarser and updose. In any case this has me reconsidering the Rule of Fifteens, that green coffee is stale after 15 months, roasted coffee is generally stale after 15 days, ground coffee is stale after 15 minutes, and espresso is stale after 15 seconds. I haven't always found the last three to be true and don't have enough experience storing greens to have a take on that. Some lighter, acidic roasts especially need a lot of rest. I think I'll relax a bit and taste what works for the particular coffee and brew method I'm using.
What do others think about this?