Open Bottle Storage: On a Shelf
Bottles left out in indirect sunlight.

Open Bottle Storage: Whisky Left on a Shelf

Most people keep their whisky on a shelf or home bar that is least partially exposed to sunlight. The same goes for many restaurant and regular bars. We wanted to see what happens to an open bottle of whisky left in that type of environment. There was a chance that pretty much nothing happened and there is no need to do anything special to preserve an open bottle of whisky. To mimicked that environment for our test we took a 750 ml bottle filled with 150 ml of whisky, and then left it on a shelf in indirect sunlight behind a double-paned glass window and two sheets of paper folded in half (see left). The room where these bottles were kept was cool most of the time, but there were a few scattered hot days when temperatures rose to 80° F in the room.


Left: The bottle of scotch after a year in indirect sunlight. Right: The control bottle of scotch.
Left: The bottle of bourbon after a year in indirect sunlight. Right: The control bottle of bourbon.

A Year Later

There are a few things to keep in mind as you go over these results. The most important is that these bottle were only opened twice. Once to create the initial fill level. The other was the final pour to give the tasters a year later. The goal of this particular part of the study is to isolate and measure the amount of change in taste that would occur over the course of one year in indirect sunlight. Another way to look at this specimen would be opening a bottle of whisky and finishing 4/5 of it. Then putting the cap back on and keeping it on a shelf. Finally, a year later drinking the last 1/5 (150 ml). This is not how most people would drink a bottle of whisky. The other thing to keep in mind is that these results are based on the shelf we kept it on. This is not going to be exactly same results of what your home or your local bar might create. Changes could be smaller or greater depending on geography, weather, etc. But this should give you a rough idea of what is likely happening at your home or your local bar.

When we speak about the differences in taste or score, it is the difference between a specimen and the control, and another specimen and the control. Not the direct difference between the two specimens.

There was also a big change in taste, but not as much as we thought it. First let us compare bottles left on a shelf in indirect sunlight to identical bottles kept in a cool dark place. Whisky kept on a shelf scored 5.38 (noticeable difference but passable), but whisky kept in a cool dark place scored a mere 1.96 (barely noticeable difference only if looking hard for one). Tasters described whisky kept on the shelf as being "flat."

Let us compare bottles left on a shelf in indirect sunlight to identical bottles kept in a cool dark place. Whisky kept on a shelf scored 5.38 (noticeable difference but passable), but whisky kept in a cool dark place scored a mere 1.96 (barely noticeable difference only if looking hard for one). Tasters described whisky kept on the shelf as being "flat." Clearly we need to get those bottles out of from the shelf and tucked away in a basement. Keeping whisky in a cool dark place is probably the single most import factor when storing an open bottle of whisky. We plan to test the effects of heat and light separately in further studies.

Clearly we need to get those bottles out of from the shelf and tucked away in a cool dark place. Keeping whisky in a cool dark place is probably the single most import factor when storing an open bottle of whisky. We plan to test the effects of heat and light separately in further studies.