How to Use Bentonite to Clarify Wine

How to Use Bentonite to Clarify Wine

Bentonite is a common additive used to clarify and fine wines. It’s great for removing protein haze and can be used to remove off aromas. But what is it? How does it work? Let’s find out. What is Bentonite? Bentonite is an impure clay formed by the weathering of volcanic ash. It is an absorbent material that is able to bond with the floating particles that cause cloudiness in wine. The main types used to fine wine are sodium and calcium bentonite. While each will contain small amounts of other minerals they are described by the mineral that is in greatest concentration. Calcium Vs Sodium Bentonite Either form may be used to clarify a wine, however, the difference between the two are the minerals that get left behind. Sodium bentonite, as the name implies, has sodium (salt) in it. After adding it to a wine it will clear what it can clear and settle out. What’s left over may be removed through racking, however, the sodium does get left behind. For commercial wineries the addition of sodium metabisulfite and sodium bicarbonate is legally prohibited by the US Tax and Trade Bureau. So while sodium bentonite is allowed it does seem that avoiding anything that adds sodium to wine is a good practice. Calcium bentonite will leave behind, you guessed it, calcium. From a wine making perspective this is much preferred over salt. However, you can go too far with this and wind up with tartrate instabilities if you add too much. Tartrate instabilities can lead to the formation of tartrate crystals. I’m sure you’ve seen these in a commercial wine before. They’re small crystals that look like a very coarse table salt. While they are harmless most consumers don’t like finding things in their wine bottle or glass. For more information on calcium vs sodium bentonite please refer to Fining with Bentonite by Christian Butzke of Purdue University (scroll down to page 3). How to Use Bentonite Bentonite is a fairly dense material and if it is not prepared correctly it will just collect at the bottom of your carboy and do nothing to clarify your wine. Here is the proper proceedure for hydrating and adding bentonite to your wine. Re-hydrate the bentonite powder by vigorously mixing 2 teaspoons with 1/2 cup water at 140 degrees F / 60 degrees C. The powder will have a tendency to clump together as it absorbs the warm water. Break up as many clumps as you can. This mixture is now referred to as a slurry. Store the bentonite slurry in a sanitized and airtight container for at least four hours. This allows the bentonite to become fully hydrated. The maximum amount of time you let bentonite hydrate is debated. Some sources say hydrate for at least 24 hours some say 48 hours. Other resources say don’t let it sit for more than 24 hours. I found 24 hours worked just fine. Add the slurry to your wine at a rate of 1 – 2 tablespoons per gallon of wine. Use one tablespoon per gallon for mild cloudiness and two per gallon for wines with a thicker...

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