All of the particulate ma􀀰er that sinks to the bo􀀰om of the
fermentation tank or vessel, including the dead yeast cells. Light and crisp whites
are racked off from the lees early in the process, but many reds and some whites
will be left to age on the lees to impart an array of interesting flavours and
fragrances; notably white Burgundy which has been emulated in chardonnays
around the world. This is known in France and the wine-making world as 'sur lie'
ageing.