2 Bn.I.KTIN (!•'»(), T. S. DEPARTMENT OF AGRICULTURE. 



<>f regular factory juices. Some of these samples were analyzed 

 immediately, and the others were sealed, placed in the storage vaults 

 of the respective factories, and allowed to remain there with the 

 regular factory juices until the bottling season, when they were 

 bottled in the presence of a chemist, under the prevailing factory 

 conditions, and shipped to Washington for chemical analysis. A 

 comparison of these two sets of analyses shows the changes in chemical 

 composition which take place during the storage period. 



The work was extended over a period of three years, during which 

 time several hundred samples were -taken and analyzed. The prin- 

 cipal factories in the State of New York were chosen for study 

 because the great bulk of Concord grape juice is manufactured in 

 this State. One representative of the Bureau of Chemistry was sent 

 to Ulster County in the Hudson River district, in the eastern part 

 of the State, and one to Chautauqua County, in the Chautauqua 

 district, in the western part of the State. Of the five New York 

 factories visited, four are located in the Chautauqua and one in the 

 Hudson River district. Later the Lake Erie district, in the State 

 of Ohio, was included. The report covering the investigation in this 

 district is given separately, because of the decided difference in the 

 process of manufacture. Laboratories were equipped and maintained 

 during the pressing seasons, one factory in each of the districts being 

 selected for the purpose. 



CHARACTER OF FRUIT USED. 



The Concord grape is a variety of Vitis labrusca L. It is one of 

 the few black grapes which come well recommended as a standard 

 grape. It is a midseason variety, and this fact in itself is reason 

 enough for its extensive cultivation, since it is less liable to frost 

 damage than the later varieties. 



A grape which deserves mention as a rival for grape-juice manu- 

 facturing purposes is the Clinton. The Clinton, which belongs to the 

 Vitis riparia-x-labrusca, lacks the foxy flavor of the Concord. It is 

 very productive and carries more sugar than the Concord. The 

 Clinton is exceedingly hardy, even more so than the Concord, and 

 thrives on soils and under conditions not so favorable to the Con- 

 cord. The color of the juice is a rich red, and the berry, although 

 somewhat smaller in size than that of the Concord, is juicy and 

 vinous. This variety is not extensively grown at present. 



The Concord grape is very juicy, of medium acidity, and the juice 

 has a rich red color. It is very hardy and productive, and, mainly 

 for these reasons and because of its color, it has become the favorite 

 for the manufacture of red grape juice. 



On the whole, the grapes used during the investigation in the 

 various factories were of good quality. The grapes of the seasons 



