Why You Should Skip In-Flight Coffee Every Time

Air travel is a stressful affair for almost everyone, so nobody will begrudge you for wanting something that will ease your nerves and help you settle into your flight. So it's a good thing that airlines provide you with a hot coffee (or soothing tea) to help you get comfortable once you've reached cruising altitude, right? Well, not to ruin your in-flight comfort, but you should probably skip that mile-high cup of joe if you're concerned about the quality of your beverage — both in terms of purity and taste.

It's no secret that airlines don't have the best reputation for serving a top-quality food and beverage experience. They also don't tend to brew what would be considered high-grade coffee for their in-flight service. As it turns out, the quality of the coffee is less about the beans than the quality of the water, and our physiological response to consuming it at high altitudes

The water the flight staff uses for coffee comes from a tank that gets filled upon landing. And while the water that's put into that tank is probably fine, the tank itself isn't cleaned with any regularity. This can cause the water to become sub-optimal if bacteria are allowed to proliferate in the tank. Tests done on certain American airlines have brought back less-than-ideal results, with one 2019 study released by Diet Detective and Hunter College NYC Food Policy Center describing onboard water as potentially unsafe. 

Granted, there doesn't seem to have been any sweeping cases of sickness among air passengers, but it's alarming nonetheless. Besides the larger water storage tank not being cleaned, the coffee pots aren't given a good scrub either. One flight attendant took to TikTok to describe how their plane's coffee makers are never cleaned, while the pots themselves are emptied between flights. 

This is an admission shared by another airline worker who, when asked by Chowhound, said that their coffee pots never leave the aircraft and therefore are only cleaned with hot water. Meanwhile, the larger jugs used to hold coffee during the day are cleaned once per day, after multiple flights. So if you're craving that caffeine fix, maybe grab a coffee before take-off or after landing.

Even if the water doesn't get you sick, it's well known that the various dissolved solids in tap water, don't much help the quality of your coffee when it comes to taste. Filtered water is the simple swap to improve the taste of instant coffee, but as we've said, it's a step airlines simply aren't taking. 

Even if you were to take water quality out of the equation, you'd still end up with inferior coffee on an airplane. Why? Because, simply put, coffee loses its taste at high altitude. Or rather, everything "loses taste" at high altitude, since your tastebuds become less sensitive in the drier, pressurized cabin air. This change doesn't just affect coffee though — it's the same reason why ordering top-tier wine on a plane is a fool's errand, and it's also the reason why airplane food is hardly ever (if at all) satisfactory.

If you still crave a coffee onboard a flight, that's your own choice, but remember that it might be better for your health and your enjoyment to just wait until you're on solid ground again.