Espresso at high altitude

[heyduke]

I just moved to Mexico and am living at 7600'. I have been buying fresh roasted coffee from a local roaster and I know it is fresh. I can't seem to get a good shot from my Anita. I have tried different grinds but so far no help. Does altitude make a difference and should I make adjustments.

[shadowfax]

I have lived in Los Alamos, NM during the summers for the last 3 years. It's at 7200 feet, as I recall. At any rate, water boiled around 197F, at atmospheric pressure. It took some getting used to. The first 2 years I had a La Valentina, and then the 3rd year I had gotten rid of Valentina and bought a La Pavoni Professional. That was actually easier, I think, altitude-wise. Honestly, I don't think that you will see a serious difference in the quality of your espresso. I got plenty of beautiful shots from both of my machines out there.

Now, of course water will boil at atmospheric pressure at a low temperature (around 195F for you, I think). But remember that espresso is under very high pressure in the puck. So you shouldn't have any issues with flash boiling on the puck.

The issue I had with an HX machine is that flushing is significantly more confusing. You may have to stop the flush before the water dance ends up that high! I would suggest flushing by volume rather than the water dance, and try to develop something consistent around that, OR get Eric's thermometer adaptor.

You might consider looking for coffees that favor lower brewing temperatures, but honestly, I don't think you should need to. You just need to play around with your routine a little, I think--vary the flush, and maybe the dose. You might also drop the boiler pressure down a little bit.

[erics]

See the second thread down in the related topics section. Bottom line is that if you bump your pstat up 0.15 to 0.20 bar, you will be at about the same temperature you were at in Columbia, MO. (7500 ft vs 700 ft.) and your brewing ritual can remain the same. OR, you could adjust your flush and timing because of the inherently lower boiler temp at your new altitude.

[shadowfax]

Bottom line is that if you bump your pstat up 0.15 to 0.20 bar, you will be at about the same temperature you were at in Columbia, MO. (7500 ft vs 700 ft.) and your brewing ritual can remain the same.

Ah, my bad, I got that part backwards

--but as near as I can tell, And as I recall, I am right that you can't follow the exact same routine, even with the boiler pressure upped, assuming that you are flushing by sight/sound of the water dance, because it will continue until the water is below brew temperature. So, I would think that either recovery will have to be longer, or, as I mentioned, you would have to use some other metric for flushing.

[HB]

I can't offer personal experience, but there's several threads in the FAQs and Favorites Digest from those living nearer to the sun:

• How does high altitude affect brewing?
• The Denver Effect?
• Water boils at 195F
• High Altitude Brewing

From what I recall of previous discussions, you'll see longer flash boiling during the HX cooling flush than someone at sea level and need to adjust accordingly. The brewing process itself is unaffected since it occurs under 9 bars of pressure, which needless to say eliminates the effect of altitude / ambient air pressure on the boiling point of water.

[heyduke]

After reading everything and putting a little thought into it I am getting shots that taste burnt and very weak crema. I am going out today and see if I can find green coffee beans and roast my own and see what happens. Thanks for all the info.

[HB]

A burnt taste is usually attributable to either too high a brew temperature or overextraction. An espresso with a bitter, sharp edge can also be blamed on an inconsistent grind or worn burrs. You've already got enough variables to figure out without adding homeroasting into the equation. I recommend finding a cafe or roaster you trust and whose product you can sample for comparison with your espressos at home. Once you've mastered your espresso equipment and barista technique, then branch out into homeroasting.

[heyduke]

I have been home roasting for years but haven't found a source for greens here yet. All of my equipment worked fine 2 weeks ago before I moved here so either its the coffee or the altitude. I suspect it may be the coffee since I have had good espresso here in San Cristobal de las Casas before.

[barry]

The Denver Effect?

Myth.

I pulled some gorgeous shots at Keystone (10,000ft) during a Roasters' Guild Retreat. All we did was turn the brew temp down a few degrees on the LM.

Naked portafilter shots look REALLY cool at 10,000ft. They don't quite behave the same as at lower altitudes... at end of cycle, the cone-of-crema would drop intact into the cup. Very strange.