New research to discover how some of the world’s greatest wines develop sweetness without the presence of sugar has pinpointed specific types of oak ageing as key, writes Jane Anson in her weekly column.

Jean-Baptiste Lécaillon of Louis Roederer has been working with upcoming Bordeaux oenologist Axel Marchal on a groundbreaking new project on oak ageing that has flowed out of that simple question of sweetness without sugar.