Today, most winemakers use stainless-steel tanks and temperature-controlled wineries to cold-soak the grapes used for their wines. In previous years, the cold weather made the inside of the wineries and tanks cold—resulting in a longer fermentation process.
Winemakers use cold-soaking to extract flavors and scents, as well as extract pigments from grapes. This technique minimizes harsh tannins while deepening the color of the grapes. However, producers are in the process of experimenting with dry ice to cold-soak their grapes.
Source: Vine Pair, November 2019