Light vs Dark Roast Coffee - A case for longer shelf life

Coffee is science, math and equations, but ironically it’s often myth that dominates the cultural caffeinated conversations. One of the most pervasive myths I hear, and one I’ve attributed to be true for a long time myself, is that coffee is just as good as stale after 4 weeks off roast.

Fake news alert - that’s not always true.

Especially in the case of lightly roasted coffee, we may be throwing out coffees or turning them into cold brew at 4 weeks because we think they’re getting stale, when in fact they’re just starting to get great.

I spoke with roaster in residence at Canada’s Lüna Coffee, Nate Welland about this recently and he had some valuable insight. Alongside Canadian coffee legend Laura Perry, the two pride themselves on roasting coffees “light and bright”.

“Laura and I both have lots of experience tasting our coffee (and many other light roast coffees ie. Tim Wendelboe, Coffee Collective, La Cabra, etc.) 4 weeks plus off roast” Nate told me. “We have found that they’re all quite enjoyable for at least up to 8-10 weeks and likely for longer still. For our coffees we’ve found they’re enjoyable after a few days to a week off roast, but do significantly improve in flavour clarity after 3 weeks of resting.” 

Nate and Laura both believe that there’s an incredible amount of raw potential in the ingredient that coffee presents, and that their duty as roasters is not to impart their signature on it, but to let the coffee sing on its own. Not only does roasting more lightly allow for a cup with more clarity and nuance, but it also helps to lengthen the life span of the roasted beans.

“This is true mainly in lightly roasted coffee because there is less CO2 created in the process compared to dark roasting” Nate explains. “The CO2 that is produced takes much longer to dissipate allowing it to age more slowly. The initial resting time just allows some of the CO2 to dissipate and helps water penetrate the coffee and not get blocked by the degassing.”

The world renowned roasters at La Cabra in Denmark recently spoke to this as well in a blog post titled “We Should Be Resting Our Coffee”. Not only is La Cabra known for their exceptional quality, but as Nate noted earlier, their light roasting preference. They encourage drinkers of their coffees to allow for a generous resting period, suggesting that their espresso  peaks “after 30 days” and the ideal drinking time for filter is also after a month.

“The idea of using freshly roasted coffee is more or less dead to us” sounds sacrilege, but when it’s from the mouth of some of the leaders in specialty coffee you should only respond with yes and amen.

I’ve always thought there was a strong case for opting to roast coffees lighter than darker, and this just proves to bolster my suggestion. More clarity, longer life, and less waste? Sounds like a no brainer to me.

Not only that, but it’ll allow you to keep more of a variety on your bar at home. No longer is each bag on a 30 day mortal countdown, so you can shake a little bit of that anxiety off and enjoy your coffees a little longer. In some cases, it could be months longer.

“Our typical window for best results is some between 3-8 weeks. Recently I found an old bag of Juiceberry (Gatomboya, Kenya) with a roast date of Jan 1, 2019 and still thought it was tasting pretty good - maybe a little age showing but not significantly.”

Has this been your personal experience with lightly roasted coffees? I assume it’ll take a little bit of time to unlearn the narrative we’ve been told about coffees going stale, and to learn to approach coffees more than a month old with an open mind. Much like the roasting process itself, slowly but surely we’ll get there.

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