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WINERY Bentonite is generally added in the range of 1–5 pounds/1,000 gallons depending on the juice or wine (it is commonplace to run a small-scale experiment to deter- mine the amount of bentonite to add to a specific wine or juice). Since bentonite is insoluble, a sus- pension must be made for it to react properly. Depending on the manufacturer, this may mean mix- ing bentonite thoroughly in water for several hours or adding it to boiling water while mixing and wait- ing for it to cool before adding it to the wine. One of bentonite's drawbacks is that it removes some of the aroma compounds in wine. A study that evaluated albariño musts and wines clarified with bentonite found that the total number of volatile com- pounds measured was reduced by 13% (Armanda and Falqué 2006: Repercussion of the Clarifica- tion Treatment Agents Before the Alcoholic Fermentation on Vola- tile Composition of White Wines, European Food Research Technol- ogy 225:553–558). However, the results further showed that although C-6 alcohols associated with her- baceous aromas were reduced, damascenone and hotrienol that help provide varietal aroma was enhanced. Thus, bentonite fining of musts seems to remove com- pounds associated with negative wine attributes while it intensifies positively associated compounds. POLYSACCHARIDE-CAUSED HAZING Polysaccharides are another cause of hazes in wine. Most poly- saccharides are insoluble in etha- nol conditions so there are few left in wine. Type II arabinogalactan proteins are the most abundant polysaccharide-like compounds. Glycoproteins are compounds with a protein core and polysaccharides attached to their exterior. The sig- nificance of the polysaccharide component to the protein is the additional solubility provided by the sugar groups. Type II arabinogalactan proteins are one of the only polysaccha- WWW.VWM-ONLINE.COM rides left in finished wines and are thought to persist because they are found in such low concentrations (20 and 50 mg/L). Other polysaccha- rides present in juice and wine are arabinogalactans, rhamnogalacturo- nans, xyloglucans, galacturonans, and pectic polysaccharides. Juice yield is often improved by © 2012 StaVin Inc. the breakdown of polysaccharides, which continues after grape crush- ing. Water that is trapped within polysaccharides by weak chemical bonds is released during their break- down. The polysaccharide content of wine is limited by its solubil- ity in ethanol. During the course Twenty years ago, we opened our doors for business. And while some years have been better than others, we can't complain. Our innovations have far exceeded our original hopes and changed for good the way winemakers approach their craft. But that's not what we're most proud of. It's the people who work with us. They've bought their own homes, sent their kids to college and genuinely love coming to work. Which, in our book is what you'd call a dream come true. ® StaVın Inc, P.O.Box 1693, Sausalito,CA 94966 (415) 331-7849 f (415) 331-0516 stavin.com NOV - DEC 2012 VINEYARD & WINERY MANAGEMENT 81