Just written up a visit to Anthonij Rupert, a South African producer with one of the most remarkable wineries you’ll ever see.
For their top reds, they use a system of barrel fermentation called Vinification Integrale. Normally, barrel fermenting reds isn’t possible because of the skins, pips and other solid bits. Some winemakers take one end off the barrel and stick it on the other end, and ferment grapes this way. But Vinification Integrale is a more sophisticated system.
One of the heads of the barrel is replaced by perspex, and a metal device is inserted into it. This contains a valve which releases carbon dioxide during the fermentation, as well as a means for stirring up the grape mass.
The barrels are filled with berries, crushed or whole, and then sealed. They are placed on an Oxoline system – a robust racking system with wheels – that allows them to be rotated a number of times a day. This makes barrel fermentation of red wines feasible.
It is not totally clear what the benefit of barrel fermenting red wines in this way is. A better integration of oak and wine?