Cork and the glass bottle

Before reliable bottles and closures, wine was stored in barrel and drunk young. It oxidised steadily and there was no practical way to mature it.

English coal-fired glass furnaces from the early seventeenth century produced darker, stronger and cheaper bottles than the wood-fired French equivalents.

Cork, from Iberian oak bark, provided an effective airtight seal. The combination allowed wine to be kept for years in a controlled way for the first time.

The consequences were large: bottle ageing became possible, vintage variation became commercially meaningful, and wines built for long maturation — Vintage Port, classed-growth Bordeaux — became viable products.