280 INTERNATIONAL CONGRESS OF VITICULTURE 



II. THE COMPOSITION OF PURE WINE FROM AMERICAN 



NATIVE GRAPES. 



By WILLIAM B. ALWOOD, 

 Stonehenge, Rio Road, Charlottesville, Virginia. 



The chemical composition of the ripe fruit of grapes does not furnish 

 sufficient data on which to base a final decision as to whether such fruit 

 will produce a potable wine. This fact was in mind when we began the 

 investigation of the composition of the fruit, therefore, wine was made in 

 commercial quantities from a number of the more important varieties. These 

 wine experiments were begun in 1907 with Norton grapes at Charlottes- 

 ville, Virginia, and the work was much extended in 1909 and subsequent 

 years, chiefly at Sandusky, Ohio. The fruit for these experiments was pur- 

 chased as regular first grade fruit obtained from the stock found at the 

 wine cellars, or purchased from the growers. The quality of the fruit used 

 was the same as could be secured by any wine maker in the district. This 

 statement does not imply that all the crops of these districts were equally 

 as good as those purchased by us, but that the fruit we used was not 

 specially selected. Naturally, it will occur that a greater or less percentage 

 of the fruit will fall below first grade, varying with the year. 



A comparison of the analyses of the fruit used in the wine experiments 

 with .the average composition of the fruit samples given in the study of 

 varieties, shows clearly the relation of this fruit to the average composition 

 of a large number of samples for the same year. From these analyses it 

 will be seen that the 25 samples of Catawba examined in 1908, 84 samples 

 examined both in 1909 and 1910, and 28 samples examined in 1911, all gave 

 a slightly better average composition than the fruit used for the wine 

 samples. The Clinton fruit samples for these years on the contrary, show 

 an average quite a little poorer than the wine sample. The fact is, this 

 variety is grown only in a small way in Northern Ohio, and samples fur- 

 nished us by growers were, in some instances, not fully wine ripe. 



For Concord the 48 fruit samples, examined in 1909, were better than 

 the fruit used for wine, while for 1910 the 30 fruit samples examined 

 as fresh fruit averaged poorer in sugar than the crop used for wine. The 

 Cynthiana crop used for wine and fruit samples of this variety for 1911 are 

 practically identical. For Delaware the crop used for wine in 1909 was 

 better than the average of 22 fruit samples examined, but for 1910 the fruit 

 samples were better than the crop used for wine. The Ives crop used for 

 wine was better than the average of fruit samples for 1909 and 1910, 

 but the fruit used for wine in 1911 was poorer than the average of the fruit 

 samples of that year. The stock used for Ives wine each year was bought 

 on the floor of the same winery and sent to us without selection. 



In case of Norton both at Sandusky and Charlottesville the fruit used for 

 wine and the average composition of the fruit samples are practically alike. 

 Thus it would appear that the variety samples examined for fruit composi- 

 tion and the fruit used for the wine experiments, vary as might be expected 

 within reasonable limits, but show clearly that the experimental wines were 

 not made from fruit of exceptional quality. 



