water to the desired final alcohol content, in the neighborhood of 40% Small quantities of other ingredients may be added to fine-tune the flavor and color; these include caramel coloring, sugar, a water extract made by boiling wood chips (the boisé of Cognac and Armagnac), and wine or sherry (blended U.S and Canadian whiskeys) Chill-Filtering Many spirits are chill-filtered: chilled to below the freezing point of water, and then filtered to remove the cloudy material that forms The substances that form the cloud are poorly soluble fusel oils and volatile fatty acids from the original spirits, and a variety of similar substances extracted from the barrel Their removal prevents the spirits from clouding when the drinker chills them or dilutes them with water, but it also removes some flavor and body, so some producers choose not to chill-filter Clouding does not occur in spirits with more than about 46% alcohol, so such undiluted “caskstrength” spirits are often not chill-filtered (Some spirits cloud spectacularly; see p 771) Serving and Enjoying Spirits Crystal Decanters Can Be Hazardous Highalcohol spirits are biologically and chemically stable and can be kept for years without spoiling One traditional and decorative way of storing them has been the decanter made of glass crystal, which derives its weight and appearance from the element lead Unfortunately, lead is powerfully toxic to the nervous system, and readily leaches from crystal into spirits and other acidic liquids Old decanters that have been used many times have been preextracted and are safe to use; new ones should either be pretreated to remove lead from the inner surfaces, or only used for serving, not storing ... stable and can be kept for years without spoiling One traditional and decorative way of storing them has been the decanter made of glass crystal, which derives its weight and appearance from the element lead... Unfortunately, lead is powerfully toxic to the nervous system, and readily leaches from crystal into spirits and other acidic liquids Old decanters that have been used many times have been preextracted and are safe to use; new ones should either be pretreated to... spirits are often not chill-filtered (Some spirits cloud spectacularly; see p 771) Serving and Enjoying Spirits Crystal Decanters Can Be Hazardous Highalcohol spirits are biologically and chemically