Clearing wine to Improve Distilled Product Quality

First published on Distillique's website in 2015 by GM Bosman

A super trick to improve the quality of your distillations.

When the mash has fermented completely (use a Hydrometer to check), wait until it is crystal clear. Then draw out the mash with a siphon, leaving all yeast and impurities in the fermentation vessel. This is called racking and might be performed more than once to get rid of all solids floating in the mash. 

By using this method you will have a crystal clear mash without yeast to distill. The mash should clear by it self in a day or two. You can speed this up by adding a clearing agent for wine or by placing the mash in a cold place.

The mash must have fermented out completely before clearing. If the mash is cloudy, it produces more “off” tastes when the cloudiness is heated in contact with the high temperature near the heather. To avoid this, rack your mash before distilling. 

There are quite a number of methods to clear fruit wine before distilling. Apart from racking, (letting the wine stand to settle solid particles at the bottom and then decanting or syphoning off the clear wine) a number of fining (clearing) agents are used. 

One of the easiest and surest manners to have a clear wine is to use Kieselol and Chitosan.

These use a two step process to clear fruit wine crystal clear. It uses both positive charged ions as well as negative charged ions to consolidate all floating particles in fruit wine. However, if you would like to go the "traditional" route, you may use betonite.

Unfortnately Bentonite only provides positive particles (and as a result only clear "half as much" as kieselol and Chitosan.) Bentonite is distinct from other clays in that bentonite is formed from volcanic ash.It has super water absorption characteristics and some even claim medicinal properties when the clay is consumed or used externally. The same quality that makes it an excellent fining agent is that which those who claim health benefits - bentonite is negatively charged and therefore acts as a magnet, attracting positively charged matter which attaches to the bentonite. 

In winemaking, this means that particulate matter in the wine will attach itself to the bentonite and eventually fall to the bottom of the fermenting vessel. Because of bentonite's absorption qualities, when added to water it can absorb more than 7 times its original dry weight. As it swells, the surface area of bentonite increases enormously as it expands to 18 times it's volume. 

As bentonite hydrates and swells, it becomes like a sponge which accounts for it's very large surface area. When it is mixed thoroughly into the wine and is dispersed throughout, the positively charged matter in the wine attaches to the bentonite. The weight of the molecules then cause the matter to drop to the bottom of the container and become what is known as "finings." There are two different schools of thought on when to add bentonite.

One school says to add it to the must/mash before you add yeast. The other school of thought suggests that bentonite be added after fermentation has been completed. There is no right or wrong answer, and with your own experimentation, you may end up with your own preference. Regardless of when you add it, the actions of bentonite are the same.

However, some believe that there is an additional benefit when adding to the must before fermentation begins. When added to the must on the first day, you may think that the bentonite will begin to work immediately, and drop to the bottom with particles attached. However, during the fermentation, large amounts of CO2 are released during the process, and this causes the bentonite to circulate, constantly, attracting more positively charged particles. This means less work for the winemaker than if bentonite is added after the fermentation. 

If bentonite is added post fermentation, it will eventually sink to the bottom with some particles, but possibly not all, so when it is added after the completion of fermentation, the wine should be stirred for several days in order to recirculate. For those winemakers that spend some time degassing their wine by stirring this isn't an issue, but for those that just want to leave the wine to degass on it's own, then adding bentonite at the beginning of the winemaking process is probably the best time. 

You shouldn't just add bentonite directly to your wine or must. Instead, you should hydrate it first. This can be a bit tricky; if you don't do it correctly, you'll just end up with water and a glob of "mud."Use 10 to 15 grams of bentonite, or about 3 teaspoons for a 20 litre batch of wine and half a cup of hot water at 50 degree C (or higher), and very slowly, while stirring the water with a fork or a whisk, pour the bentonite into the water. Stirring vigorously will help to ensure a more uniform mixture of bentonite and water, which can then be poured into your must or wine.

Of course, you should stir your wine immediately upon adding the mixture to it. 

Bentonite may be added to any type of fruit wine. It may seems weird to add clay to clear wine, but don't worry - with the use of bentonite, you'll in fact be ensuring less dirt and particulate in your finished wine!

If bentonite does not clear your wine enough, rather use  Kieselol and Chitosan for crystal clear fruit wine. 

NOTE: Bentonite permanently deactivates enzymes like pectolase.

Only use bentonite after the enzymatic reactions (such as using pectolase to convert pectins/protopectins) has been completed.