Denver

[Emily Kryska]

Hey you guys,
I'm wondering about the Denver effect. We've talked about it at work (thank you Shomer) but our crema just doesn't stay, except with a bit of weird work. Any suggestions, and what do you think..? Also, our coffee world is growing y'all! How can we make it awesome for all of us? I know there are suggestions out there. Ok. Thank you so much! Emily

[Vajra Rich]

Degassing and nitrogen flushing(Aging with limited oxidation) is our only hope.

[Emily Kryska]

Oh Vajra! Our only hope? Would you explain why exactly, as in how it effects the coffee and such- the science of it...

[Vajra Rich]

Roasted coffee contains CO2 and that is part of what makes up the matrix we call crema. At this altitude there is a great deal less atmospheric pressure than there is at sea level and therefore the CO2 in the creama wants to giddyup and get out(Big Bubbles!) All the conventional wisdom about espresso extraction in the USA was formed at much lower altitudes where espresso works well 48 hours after roasting and maybe under great storage conditions still pours well up to 10 days after roasting.Some say two weeks.
We get big bubbles for a long time. In order for us to have crema that lasts we need to age the coffee in order to allow some of the CO2 to escape. The only problem is that the longer the coffee oils are exposed to oxygen the more we risk rancidity. Oxidation causes oil to become rancid. Dark roasted espresso is a good example. Many peaple are used to this taste and dont feel like they are getting their moneys worth if they dont get some portion of rancidity in their cup.
We am currently doing some testing on aged espresso that has been flushed with nitrogen in order to stop the oxidation process. Hopefully what we will have is stable tight bubble crema and espresso that is sweet!!

[Nolan]

Vaj, what do you think about us for instance? Lighter roasted espresso with almost no oil on the surface (light oil at 12 days). Are the oils inside the bean still oxidizing? I think our espresso tastes great 10-15 days out of the roaster (no valve packing), but Im at a loss as what to do for the USBC. We are doing three different roast days for the comp but it seems like a hassle! I guess thats what I have to do if Im going to be serving the best coffee I can. Oh the effects of less oxygen and less atmospheric pressure!

[Vajra Rich]

Lighter espresso as you just described does not oxidize as quickly and in my not so humble opinion is a great deal more yummy! However some oxidation is inevitable. As far as I know the only way to eliminate oxidation no matter what degree of roast is to cool off a roast in an oxygen free chamber and immediately bag it up. Illy has some super high tech packaging and I believe they claim to be able to keep coffee fresh indefinitely. These claims are apparently a load of old bullocks! I believe up here your espresso tastes good at two weeks assuming it is stored properly as I have had the same experience with ours. However because of oxidation, I would say it would taste better much sooner if we didn’t have the altitude issue.
I would take with you some that is 12 days old so that it can be opened a day before the competition. I would also take some that is between 48 hours and six days old so that you can taste both and decide then which one to use. I’d be willing to put money in the later because the crema will be awesome and almost make you cry when you see the difference. Not only will the crema be more durable but the aromatic will be more abundant, which will also make you cry. I recently roasted up some espresso here and took it with me to Mexico to a café at about 10 feet above sea level. I was pulling shots on a GB5 and they were beautiful at about four days after being open for one day.
Break your F’n legs out there man! Do you want to borrow those two portafilters I mentioned with the right spouts?