CONCORD GBAPE JUICE. 17 



stored juices containing the least alcohol have a higher cream of 

 tartar content than those with greater amounts of alcohol. It 

 seems improbable, however, that the small amounts of alcohol con- 

 tained in the juices in question could be solely responsible for this 

 difference in cream of tartar content. 



Table 9 gives a comparison of the analyses of 16 juices, comprising 

 8 sets, half of which were analyzed after 4 months' storage and 

 half after 16 months' storage. Each two lines of data in the table 

 represent a sample of the regular juice bottled after 4 months' storing, 

 and the same juice after an additional storing of 1 year. Although 

 the difference is very marked in the case of the ash and tannin con- 

 tent, it is not very pronounced in the other contents. The data 

 show that 4 months of storing is not a sufficient time for complete 

 precipitation. 



BOTTLING AND PASTEURIZING THE TRADE JUICE. 



The next step is that of pasteurizing the juice in the bottle. This 

 operation should be very carefully superintended because any defect 

 leads to fermentation and consequent loss. The pasteurizing tem- 

 perature varies in the different factories, ranging from 160° to 175° F. 

 As a rule, when the bottles are filled cold, the juice reaches the pas- 

 teurizing temperature in about 10 minutes, is allowed to remain at 

 pasteurizing temperature for about 30 minutes, and cooled off in 10 

 minutes. When filled hot, from 20 to 25 minutes at pasteurizing 

 temperature are sufficient. The length of the heating period varies 

 with the size of the package to be sterilized, 55 minutes sufficing with 

 pint and quart containers. Packages holding more than a quart 

 should be filled hot. 



The siphoned juice is strained through several thicknesses of bur- 

 lap, and collected in a vat connected with the filling machines. The 

 practice of filtering the juice through paper pulp, employed in some 

 factories, did not seem to improve the appearance of the juice very 

 much. The packages are filled with the juice by means of beer 

 fillers, and immediately sealed, either with corks or metallic seals. 

 When corks are used it is necessary to heat the juice before bottling 

 to avoid blowing. A temperature of about 160° F. is ordinarily used 

 for this. When metallic seals are used for smaller packages it is not 

 necessary to heat the juice before filling them. Packages holding 

 more than a quart should, however, be filled hot to avoid breakage. 



MANUFACTURE OF GRAPE JUICE IN THE LAKE ERIE DISTRICT. 



The method of manufacture of the juices from the Lake Erie 

 district differed greatly from the methods which have been described. 

 The grapes were not stemmed before heating, and the juice was 



