Effect of sunlight and summer heat on coffee

[Fullsack]

My coffee had been tasting terrible after only a few days, in both of my machines and I couldn't figure out why. Then I noticed with the change of the season, the sunlight had been coming in the kitchen window at a different angle and shining on the coffee jars on the counter. Then I remembered, about a pound of coffee that I split between home and work. I'd left the work coffee in my trunk for only half an hour on a hot day and it was awful. The other half of the batch at home tasted good. Moral: roasted coffee always needs to be kept in a cool place.

[HB]

I've wondered about shipping UPS Ground during the summer, especially if the shipment gets delayed over a weekend. I assume UPS warehouses are not climate controlled. For what it's worth, I haven't noticed a degradation in coffees in summer independent of how it's shipped.

Peter and I were discussing this awhile back; he mentioned that their tests showed no difference between coffees shipped next day air and then stored versus coffees that made the trip by truck. They even tried a few variants, e.g., intentionally storing coffee in the back of a hot truck. Tim (Counter Culture Coffee's head roaster) elaborated a bit in his note:

We did some pretty extensive work on this. Although I agree that coffee needs to be stored in a cool place, I do not think that 30 minutes in a hot truck would make a drastic difference. We left ours in a hot truck for a week and still our triangulation proved to have greater personal difference between coffees that the coffees themselves. (A side note though is that was only 1 test, to give a 100% answer I would want to repeat it many times. )

However the direct sunlight on the coffee jars I do think will kill it pretty quick.

[Psyd]

Moral: roasted coffee always needs to be kept in a cool place.

There are some that suggest that coffee should never be refrigerated, but since my house gets over ninety-five on occasion (with the Astoria adding her two cents to the kitchen environment) throughout the summer, the 45 degrees of the 'fridger seems to be the best place for beans to be, given the choice.