There are three weapons for combating cloudiness in wine. These include the addition of protective colloids, heat treatment, and ultra-filtration. A fourth might be mentioned. It involves the utilization of protective colloids, such as tannins, which may be naturally present in the beverage.
Protective colloids are substances like gelatin, dextrin, or gum arabic. These serve to keep liquids clear by preventing the precipitation of matter in solution. In wines, the problem of cloudiness is complicated and has no single, simple answer because there are many causes. Gelatin, dextrin or gum arabic may help or hinder, according to circumstances.
Ultra-filtration is a modern expedient which helps to control cloudiness. When colloids, whether naturally present or artificially added, are a hindrance rather than a help, they can be filtered out along with any particles which may be clouding the wine. An ultrafilter uses a filter membrane which, to all appearances, has no holes and would not allow a liquid to pass through it. Transparent cellulose, for example, can be used in this way for some ultrafiltration purposes.
In the heat treatment of wine to prevent clouding, the temperature used depends on the kind of wine, the type of cloudiness and the kind and amount of colloids present. The heat method is especially applicable to red and white wines, in which it has effects quite similar to those brought about by adding gum arabic
Digest from "Colloidal Phenomena in Wines", by J. Riberean-Gayon. Bulliten de la Societe Chimique (Series 5), 3, 603, 1936. (Published in France)
|Gelatin Weight||Liquid Weight|
|1 Tablespoon (1/4 oz.)||1 pint water|
|8 Tablespoons (2 oz.)||8 pints water (1 gallon)|
|4 oz.||2 gallons|
|10 oz.||5 gallons|
|20 oz.||10 gallons|
|2.5 lbs.||20 gallons|
|5 lbs.||40 gallons|
1. Add gelatin to room temperature liquid, stir and let gelatin hydrate for two minutes, in roughly 1/3 of total liquid to be used.
2. Add additional liquid at temperatures of 140°F. to completely dissolve, and for pasteurization if necessary.
3. Place contents with lids over liquid and cool to 40°F.
4. Product is now ready to use.
For normal clarification use 1 lb. of Great Lakes Brewers Gelatin for each 100 bbls. of beer. When excessive proteins are to be removed, 1 1/2 lbs. are recommended. For each pound of gelatin, add 6 quarts of cold water (55 - 60° F.) As soon as this is absorbed, add 26 quarts of hot water (185°F.) and stir until dissolved - about 15 minutes. The solution should be added to the beer while it is being pumped into the aging tanks, by proportioning if possible, otherwise when the tank is about 2/3 full. The solution mixes best with the beer when the solution is about 130°F. The web formed by the gelatin solution should settle out in within 5 to 7 days, depending upon the size and type of storage tank. A longer period is not detriment to the beer.
Gelatin in the dry form is best stored at 40 - 70 °F. where the humidity is low. When thus stored, it will not lose its strength, but once in solution, the bloom will drop at the rate of about 25 points every 6 hours. For this reason the solution should be prepared just prior to adding the beer.
By using Great Lakes Brewers Gelatin, it has been found that yeast, proteins and other matters are more easily removed. By this clarification, most brewers are able to run 3 to 4 times as much beer through their filters before changing. This results in a saving in labor costs and other filtering materials greatly in excess of the cost of the gelatin.
Gelatin / Medical 235 / Wound Care
Material Description: Gelatin / Medical 235 is a fine powder Type A gelatin. It is produced carefully to meet both physical and chemical standards set forth by US Pharmacopoeia.
Application: This product is especially granulated to absorb water more rapidly than larger granulated particles. It is specifically designed to work with other fine mesh substances synergistically, and provide the safety and protection your product warrants. This product is specially designed for use in wound care and ostomy products.