Frontenac, relatively recent dark-skinned hybrid grown for port-style wines, in the Upper Plains and American Midwest. It high acidity generally requires some residual sugar. The mutation Frontenac Gris has produced some white wine but the more recent mutation Frontenac Blanc may well prove more popular.
ยฉ Jancis Robinson and Oxford University Press 1994, 1999, 2006, 2015
