Christie Kiley on February 19, 2015 15 Comments Bentonite is a common addition to winemaking used to clarify wines and is generally used only for white wines. It removes any protein haze and can also be utilized to fine any ‘off’ aromas. photo credit What is Bentonite & How Does It Help Wine? The use of bentonite is usually needed for white wines first, before the fermentation has been started. You will need to make a ‘slurry’ of bentonite to add it to wine, much like you make a slurry out of flour and water before you add it to any sauce in cooking to thicken it. However, in this case, we are not trying to thicken the wine. The bentonite is impure clay created by weathered volcanic ash. The material is very absorbent and it binds and bonds onto any floating particulates which cause haziness or cloudiness in wine. Once it binds to these particles, it will eventually fall out of the wine helping improve its overall clarity. Two Types of Bentonite There are two types of bentonite used for fining wine; sodium and calcium. They both contain different minerals, which will probably be listed on the package. However, none of these minerals will actually be ‘added’ to the wine. The purpose of adding any fining agent is to have it bind on these clouding proteins and eventually precipitate out of the wine to the base of your fermentation container. They are easily removed by racking the wine and syphoning the wine from the surface ever so carefully so as to leave the solids behind. If you utilize sodium bentonite, you will mix it with water and gradually add it to the wine, but once it is mixed into a solution, the sodium in the form of salts are left behind. As for calcium bentonite, it leaves behind calcium. This is preferred to salt, however, you have to be careful how much you add as you could later be dealing with tartrate instabilities (other solids which precipitate out of wine as salts), but most are harmless. 4 Steps to Using Bentonite Properly You must utilize the bentonite properly or it will not clarify your wine at all. Here is what you do: You want to rehydrate the bentonite powder by mixing vigorously every 2 teaspoons per ½ cup of water around 140°F(6°C). If the water is not warm enough, it will clump and fall to the bottom of the container. Mix it well for a long time until you can dip your hand in it and it just appears and feels smooth with everything dissolved. For small batches, you can just use a common kitchen whisk. For larger operations, they actually use a long wand attached to a drill bit with a propeller and place it in the container with the drill running to mix it well. Some people will tell you to let it sit for 24 hours before use so that it is fully hydrated, but that is not necessary. Add your slurry to the wine at a ratio of one to two tablespoons per gallon. One being for mild haze and two for thicker. Stir the mixture slowly into the wine, but try not to do so by mixing in too much oxygen. A line with a gas line while you do this can help. From here, you can let your juice or wine rest for about 4 days more or less until the wine/juice is clear. From this point on, you can rack your juice/wine from the solids and go on with the next step in your process.
Ivan says February 20, 2017 at 4:43 am Great! I want to share chemistry of bentonite when is added in to the wine Reply
Jonathan says September 12, 2017 at 10:55 am If I forgot to put the bentonite before fermentation can I add it on step 2? Reply
JP says June 5, 2018 at 10:17 pm I believe you can. Many solids will settle out of the wine naturally in step one without adding anything such as bentonite. As the yeast dies off, they settle out pretty easily. Adding bentonite after first racking should still work just fine because it locks onto the suspended particles that cause the wine to look hazy. These particles don’t settle very easily by themselves so bentonite helps the little boogers settle to the bottom faster. Reply
Khraw says October 6, 2020 at 1:01 am After adding the bentonite, how many days we can keep the wine along when bentonite, is it for 4 days or more than that Reply
Jaret says September 15, 2017 at 11:38 pm Yes that is fine, kits usually tell you to add it when throwing your primary together but adding it later wont hurt a bit. Remember do not go overboard and let the bentonite do it thing. Adding too much will strip aromas and flavors. Reply
Curt Willis says December 3, 2017 at 8:34 pm I am planning on adding bentonite to fine as batch of wild grape wine that has been sitting under air lock for just over two years. I am racking every 3 months and am still getting sediment. Will the bentonite reduce some of the foxiness of this wine? Age has improved it quite a bit already. Reply
mary says October 8, 2018 at 11:54 pm hi. is bentonite acid activated or it’s simply a pure bentonite? Reply
mary says October 9, 2018 at 2:31 am hi. is this bentonite acid activated or just pure bentonite? Reply
cyril tarrant says February 17, 2020 at 11:44 am Everywhere it says that bentonite clarifies wine and should be added AFTER fermentation but in the kit is says to put it in the primary first? Please someone explain. Reply
Ken says November 13, 2020 at 11:50 am You can do it either way it still works. I just started a red kit and I’m going to add it on day 3 when the fermentation is going. I’m also going add a little less than what I read online. Reply
John says May 21, 2020 at 6:26 pm 140 degrees Fahrenheit is 60 degrees Celsius, not 6 as in your instructions. Reply
David Wahlstrom says August 12, 2020 at 10:26 pm Is bentonite clay from cat litter unscented okay to use I mean it’s essentially the same thing isn’t it? Reply
Steve says October 31, 2020 at 6:53 am Cat litter is similar but not the same. Unscented cat litter has a mixer of red clay and bentonite clay. Cat litter also contains trace amounts of heavy metals. You can purchase food grade sodium or calcium bentonite clay powder by the pound on Amazon. I would suggest purchasing the food grade bentonite. Reply
