There are many variables that can influence the perception of wine. The most likely answer to why a wine might taste different when you’re enjoying it outside is the temperature change, especially if it’s also affecting the temperature of the wine. When a wine gets too cold, the flavors can seem muted. Too warm, and the perception of the alcohol might be amplified, making the wine seem disjointed or off balance. Warmth can also amplify flaws in a wine.

Other potential “influencers” when it comes to how we perceive a glass of wine include humidity and atmospheric pressure, light, sound, the aroma of the air, glassware and, of course, bottle variation. A single fruit fly can also ruin the taste of wine for some of us. Atmospheric pressure is known to affect our sinus cavities and the way things taste and smell, which is why wine can seem harsh in the pressurized atmosphere of an airplane.

It’s difficult to pinpoint all the differences, because there’s no easy way to measure the way a wine is perceived.