Ask Wine Wizard

Would you recommend using dry ice to control the temperature of must?


John Ivica Duich • Chicago, Illinois asks,

In preparation for this season’s crush I have been thinking about several different ways of protecting my wine from oxidation. After primary fermentation and MLF the CO2 levels in my primary vats will quickly drop. I was thinking about investing in a small tank of Argon to keep the primary gassed during maceration. I have also heard of people dropping in small pieces of dry ice in the must then covering the tanks after punching the must down. Would you recommend using dry ice on the must?

Dry ice can be a tremendous help for small-lot winemakers in the grape or must stage. Dry ice is really just frozen carbon dioxide gas and will cool the air (or liquid) where it’s placed whilst releasing carbon dioxide gas as it sublimates. Dry ice never melts; unlike frozen water it goes directly from the solid to the gaseous phase, releasing those white, wispy “mad scientist” bubbling mist effects. Trust me, the Wine Wizard is a fan! I like to float dry ice pellets in a pie tin on top of my half-ton bins of must for an effective and simple CO2 blanket to help ward off bacterial infection during a cold soak. Sometimes I even put dry ice pellets (a few pounds/1 kg) in my half-ton picking bins if my grapes have a particularly long way to go from field to the winery. This cools down the bin slightly and the pooling carbon dioxide gas helps retard bacterial growth along the way. You could pop a couple of dry ice pellets into your carboys before filling them instead of
Response by Alison Crowe.