Brandy pomace

Methanol. In grape wines and brandies methanol determination is rarely necessary except where excessive amounts of pomace are used Italian regulations limit the methanol content for this reason. With fruit wines and fruit brandies the legal maximum can easily be exceeded, and therefore an accurate determination of methanol is required. 

Brandy is the product prepared by distilling wine, wine lees and/or grape pomace and often by blending the results of these operations. 

Third.—Distilled from grape pomace which may have been refermcnted with sugar and water. The term grape pomace includes the skins, pulp and possibly the stems of the fruit. These brandies are naturally of very inferior quality. They are known as Marc Brandies or eau de vie de marc" from the French term for pomace. During prohibition a similar product was supplied in the United States by bootleggers under the name grappo. ... 

The alcohols above ethyl in the series are generally spoken of as higher alcohols. An extensive literature on their presence in brandy has developed because of their importance to the organoleptic character of brandy. Much less information is available for wines. The chief higher alcohols found are isoamyl (3-methyl-l-butanol), active amyl ((—)-2-methyl-l-butanol), -propyl (1-propanol), isobutyl (2-methyl-l-propa-nol), n-butyl (1-butanol), and (—) sec-butyl (2-butanol). Others doubtless occur and will be identified as better methods for their separation are developed. Buscarfins (1941) fractionated (under vacuum) a fusel oil from wine pomace and identified amyl, propyl, isobutyl, butyl, and isopropyl (2-propanol)alcohols as esters and higher alcohols up to decyl. No hi er secondary alcohols were found. The residue consisted of esters, fatty acids, furfural, cylic bases, and hydrocarbons. Only acids with an even number of carbon atoms were demonstrated. The unsaturated acids oleic and linoleic were present in small amounts, presumably from the seeds. Ethyl esters were more important in amount than amyl esters. There was 3% furfural, 5.5% fatty acids (free and esterified), 30.9% alcohols (free and esterified), and 1.6% hydrocarbons (terpene). Dupont and Dulou (1935) demonstrated sec-butyl alcohol in a technical propyl alcohol that had been produced from fusel oil. 

The left over stems, skins and seeds provide the pomace. It is used as feed or fertihzer, or is fermented to provide pomace wine. This is consumed as a homemade drink and is not marketed. Pomace brandy is obtained by distillation of fermented pomace. The average must yield is 75 1/100kg grapes. Of this, 60% is free juice (must), 30% press-must and 10% must from the second pressing. 

The fermentation residue or pomace is processed into yeast-pressed wine or yeastbrandy, into wine oil (for brandy essence) and into tartaric acid. The left-over pomace is used as a feed or fertilizer. Pomace wine, obtained by fermenting a sugar solution containing the dispersed pressed-out pomace, is made only into a household drink and is not marketed. 

Da Porto, C. and Freschet, G., Grape pomace storage on an industrial scale in containers Effects of refrigeration on the volatile composition of grappa brandy phlegm, Industrie... 

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