flame but soon the advantages of a bain-marie or steam distillation to obtain a better product became obvious. Modern refinements included the distillation of pomace under vacuum, the use of varietal grapes and ageing in casks of various types of wood to improve the flavor of the liquor. Oak is the most used, but some more expensive grappas are aged successively in casks of acacia, ash and cherry-wood, an innovation introduced by the Marzadro Distillery. In Sardinia, Grappa is colloquially known as Filu è Ferru (iron wire), as most of the distillation was illegally home-made to avoid customs and excise taxes. The illegally distilled liquor was bottled, sealed and then buried in orchards, fields and pastures, awaiting sale. A bit of iron wire was tied around the bottleneck, barely protruding through the soil; after some time the wire would rust and disappear completely save for a faintly brown-red stain to the topsoil on the spot where the bottle was buried. While the peasant distiller could easily recognize the colored spot, the urban-schooled Guardia di Finanza officers were generally unable to tell the difference. Tasting Professional tasters distinguish among four categories of grappa: young, cask-conditioned, aromatic, and aromatized. Grappa tastings begin with young grappas, then continue with cask-conditioned and aromatic grappas, and finish with aromatized grappas. The flavor of grappa, like that of wine, depends on the type and quality of the grapes used, as well as the specifics of the distillation process. When the tasting involves more than one grappa from the same category, the examination begins with the grappa that has the lowest alcohol content and concludes with the product richest in alcohol. When two grappas have the same alcohol content, the tasting begins with the smoother and less markedly flavored product, which the organizer of the tasting will have selected beforehand. Another way to "taste" grappa is by rubbing a small amount on the back of the hand and sniffing. If the aroma is pleasant, the grappa is well made. Impurities in grappa come out in the vapor and can be easily distinguished in this way. After each tasting, and before sampling another glass, some tasters recommend drinking half a glass of milk to refresh the taste receptors on the tongue. Various other food products can help stop taste-characteristics of one grappa from "dragging" or carrying over to the next. Foods that are effective in this role as