Tasting and collecting

Storing an open bottle of whiskey

2 minute read · The Blending School

Whiskey does not spoil, but an open bottle does change. Three variables control how fast, and all three are easy to manage once you know them.

How long does it last

A full, sealed bottle: essentially forever. An open bottle that is mostly full: years with little change. An open bottle with a couple of ounces in the bottom: months before it softens noticeably. The variable is air, and specifically the ratio of air to whiskey in the bottle.

Air: the one that matters

Every time you open a bottle, fresh oxygen comes in and volatile aromatics go out. The more headspace, the more oxygen sits against the whiskey between pours. This is oxidation, and it usually softens and flattens a whiskey over months. The practical rules: keep bottles sealed tightly, do not leave them open on the counter, and when a bottle drops below about a third, either finish it in a reasonable time or decant it into a smaller bottle to shrink the air gap. Sample bottles in the 100 to 200 ml range exist for exactly this.

Light and heat

Sunlight degrades whiskey and fades its color; a cabinet beats a sunny shelf every time. Heat speeds every unwanted reaction and, with a marginal seal, pumps air in and out as the liquid expands and contracts. Steady room temperature in the dark is the whole recipe. More detail here.

Upright, always

Unlike wine, whiskey should never rest on its cork. High-proof spirit in constant contact with cork degrades it, and a degraded cork crumbles into the bottle or lets air through. Store upright; the cork stays healthy for decades that way.

The infinity bottle answer

Those last two ounces that will otherwise slowly oxidize into something dull are exactly what an infinity bottle is for. Pouring the end of a bottle into the house blend solves the storage problem by removing it: the whiskey lives on inside a bottle that keeps getting topped up, with a small headspace and a purpose.