How long can a bottle of champagne last unopened without losing its signature fizz?

In a recent study published in ACS Omega, researchers measured the dissolved carbon dioxide concentrations in 13 different champagne vintages supplied by Champagne Castelnau. Showing prolonged ageing on lees ranging from 25 to 47 years, the vintages were stored in both standard 750mL bottles and 1.5L magnums, all sealed with the same model of crown cap.

As expected, it was found that the amount of carbon dioxide inside the bottles decreased the longer the bottles aged. For example, the oldest vintage (1974), held in 750mL bottles, lost nearly 80% of its initial carbonation during 47 years of lees ageing. The researchers also discovered that magnums could preserve bubbles better during prolonged ageing than the same vintages elaborated in standard bottles.

Based on this data, the researchers created a formula to calculate champagne’s shelf-life, predicting that a standard 750mL bottle, having experienced prolonged ageing on lees, would last 40 years before it would go flat when poured into a glass. In contrast, a 1.5L magnum would last 82 years. The 3L Jeroboam was predicted to keep its bubbles for 132 years, after which bubble formation would become impossible after disgorging and service.

So, there you have it! Size truly matters when it comes to maintaining champagne’s trademark sparkle, and this latest study has great implications for both cellar masters and consumers alike. For the cellar master, choosing larger format bottles ensures that the bubbles are preserved for prestigious cuvées that require extended ageing. As for consumers, opting for bigger bottles means more time to savour the celebration and enjoy the bubbly!

Discover larger format bottles of champagne here

Selection of magnums