Specialized wines will have often have passed through similar sequences of grape maturation, harvest, and fermentation (which may or may not be carried to completion) typical of more normal wines but are, nonetheless, treated somewhat differently. Wines developed for shipment, such as Port, Madeira, and Sherry, discussed here, and wines developed from grapes infected with the fungal ascomycete known as Botrytis cinerea (aka the Noble Rot), wines produced from frozen grapes (Ice wine), and wines produced from grapes similar to those grown in the Champagne region of France and destined to become “sparkling wines,” to be discussed subsequently, are all slightly different from the general types already described. And yet, because the compounds initially found in the grapes enjoy the same precursors and are doubtlessly very similar save for their terroir and their individual genomic and epigenomic differences, all but the final treatments they undergo are somewhat similar. Indeed, in that vein, Port and Madeira wines apparently originated in Portugal and Sherry in Spain, and the preferred grapes from which the preferred beverages are made continue to grow in and or near the initial locations. Other growing regions do try, with greater or lesser success, to create similar beverages. Port, Sherry, and Madeira wines are all called “fortified” beverages. They are generally higher in alcohol content and other flavorings than those produced by typical fermentation processes and have one or two additional steps that are associated with their processing. The first step involves producing a “distilled beverage.” In this process a portion of the wine produced in the usual way by fermentation is subjected to the process of distillation in the presence of air. In that process the wine is heated above the temperature at which it vaporizes (different components vaporizing at different temperatures) and then the vapors produced are removed, condensed, and separated from the residue. Low- boiling materials such as water (H2O, the major constituent of wine), methyl alcohol (methanol [CH3OH] of which there are traces), acetaldehyde (ethanal [CH3CHO] produced by oxidation of ethanol), and perhaps surprisingly, ethyl alcohol (ethanol [CH3CH2OH]), as well as other low-boiling components (e.g., some esters) are removed.
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