REPORT OP COMMITTEE ON PUBLICATION 281 



The wines presented in the table comprise samples from all the varieties 

 of grapes treated in the paper on chemical composition of American grapes, 

 but in most cases we have not made wine from all these varieties each year. 

 However, in a number of instances we have made several wine samples 

 with the same variety in a season. The data given is from an experimental 

 wine which, in all particulars, is typical of ordinary wine manufacture. 



In these experiments the fruit was crushed by machines like those used 

 in the regular wine plants. In case of white wine, the must was expressed 

 on a power hydraulic press. A dial gauge was used to register the pressure, 

 and the pulp was exhausted as completely as possible at 1,500 pounds direct 

 pressure. The fresh must, both free and press musts, were then assembled 

 in casks in the cellar, where the fermentation was carried to completion 

 practically, as is customary, in the cellars. After precipitation was well 

 completed the young wine was racked from the lees and transferred to clean 

 casks. The quantity of the original must used in an experiment varied from 

 50 to 100 gallons and in some instances more. 



In case of red wines the fruit was crushed on machines as given above 

 and the pulp with the must was transferred to vats on the first floor of the 

 building. Here the fermentation was carried on to a point of attenuation 

 such as was thought proper to produce the normal wine from the variety in 

 question. The sugar remaining in the pomace varied from .5 per cent to 

 1.8 per cent of the pressed pomace. The chemical sample of the fresh fruit 

 used for both white and red wines was obtained by taking frequent portions 

 of the pulp and juice as it was transferred to the vat. These portions were 

 mixed and then a chemical sample taken. 



The young wine was drawn from the vats when the fermentation had 

 reached the point desired and the pulp was pressed thoroughly on the 

 hydraulic press at 1,500 pounds pressure. Both the free run and the press 

 wine were united in casks in the cellar as the experimental wine. The casks 

 were given the ordinary care usual in wine cellars, and each sample was 

 racked from the lees, after sedimentation, during the first winter. After this 

 the wines were racked as conditions required to remove them from any 

 sediment which precipitated. None of these samples have been fined, filtered, 

 or treated in any wise to ameliorate or alter their condition. They have 

 been held strictly as chemical samples for the purpose of technical study. 



The full investigation comprised a study of the organic properties of 

 these wines and complete ash analyses, but for the present purpose I present 

 only the data on specific gravity, alcohol, solids, sugar and total acid. Ratios 

 of acid-sugar in the fresh fruit, acid-alcohol and sugar-alcohol in the dry 

 wines are given. My reason for limiting the data presented at this time is 

 that I wish to treat only the organic composition of these wines in relation to 

 the fruit from which they are derived without introducing other particulars. 



The table presents first, the data on the composition of the fruit used 

 for each wine sample, and then two analyses of the wine produced from this 

 fruit. The first analysis of each wine represents the young wine as soon as 

 fairly well sedimented and the second analysis given represents the dry wine. 

 The analytical results on the wines are given only for solids, sugar, alcohol 

 and total acid. Or, in other words, each analysis covers these elements given 

 in the analyses of the fruit, with the addition of the determination of the 

 alcohol derived from the sugar. 



