Malmsey is a noble white wine grape variety responsible for the sweetest of all madeira. Madeira is arguably the world's finest fortified wine style, yet it is unarguably the world's longest lived. Indeed, Madeira can keep for a century or more, following long ageing without temperature control, in large casks.
The term Malmsey is the Anglicized corruption of Malvasia, a name as diverse in its usage as it is responsible for the infinitesimal number of white skinned grape varieties and their progenies, many unrelated genetically, that share the name throughout southern Europe. One also hears the term Malvoisie.
The name Malvasia hails from Monemvasia, a port which was important in Ancient Greece. The name was used from ancient times and throughout the Middle Ages for a litany of sweet wine styles. These were prized for their robustness and longevity and in cooler months, for their warming qualities.
Today, after being threatened by phylloxera during the 1870's when much of Madeira's vineyards were uprooted and turned over to sugar cane, Malmsey, especially the subvarieties Malvasia Candida and Malvasia Babosa, have been repatriated to the craggy mountainous vineyards of the island.
Malmsey is generally grown on the lower southern slopes of Madeira around Câmara de Lobos, and is harvested later than its noble brethren, Sercial, Verdelho and Bual. It is then fermented on skins for balancing texture, grip and aromatic lift, before fortification arrests the ferment to leave somewhere in the vicinity of 3.5 and 6.5° Baumé of residual sugar. Malmsey's fulcrum however, is the saline acidity that allows for freshness and drinkability.