Expert view: guide to decanting

How many of us have a wine decanter stowed away somewhere at home? Or, having ordered a bottle of aged Bordeaux, watched the sommelier carefully decant it and wondered what exactly is going on.

Olivier Marie, head sommelier at Coq D'Argent for the past 15 years explains that there are two very good reasons for decanting wine:

1. Removal of sediment caused by polymerisation (a complicated process that occurs when phenolic compounds like tannins form a chain)
2. Aerating it to enhance the flavours and aromas

Not all wine requires or benefits from decanting, Olivier explains. Cabernet Sauvignon and Shiraz are two varieties, which age well and are often good candidates. Some rich white Burgundy wines gain from aeration, but your £5 Chilean Cabernet Sauvignon will have gone through "heavy handling" so won't need decanting. By this, Olivier means wines that have undergone filtration are less likely to benefit.

View the gallery below to watch Olivier explain each stage of decanting: