variety when obtained from different localities. Previous investi- 

 gations of the Department show that the tree-ripe peaches are 

 materially richer in sugar than the same fruit picked market-ripe, 

 the average sugar content of three varieties having been found to be 

 7.50 per cent of the peach pulp in the tree-ripe fruit and 6.04 per 

 cent in the fruit when market-ripe. The juices reported in Table 1, 

 therefore, would probably have been richer in sugar if they had been 

 prepared from tree-ripe instead of from market-ripe fruit. On the 

 other hand the sugar may have become concentrated during the time 

 which elapsed between picking and analysis. The analyses there- 

 fore may be considered fairly to represent the composition of peach 



juices from fruit picked when practically mature. 



\ 



TABLE 1. Composition of the unjermented juices of peaches used in the preparation of 



vinegar stock. 



a Pulp crushed by hand. 



i> Juice was not expressed from the sample of ground peaches until after yeast had been added. Con- 

 siderable inversion probably occurred before analysis, owing to the presence of invertase in the yeast, 

 hence the values lor reducing sugars are too high and those for sucrose too low. These figures are therefore 

 excluded from the averages. 



c Average of seven determinations. 



In Table 2 the average composition of these juices is compared 

 with analyses of peach juices made by others 6 and with the average 

 composition of apple juice. c The peach juices the analyses of which 

 are shown in Table 1 are nearly 2 per cent richer in total sugar than 

 those previously analyzed by others, but are 1 per cent poorer in 

 sugar than average apple juices. Both series of analyses of peach 

 juices show that peaches contain much more sucrose than apples and 

 are also richer in acid. 



<*U. S. Dept. Agr., Bureau of Chemistry Bui. 97, p. 21. 



b Averaged from the review of literature regarding the composition of peach juices, 

 given in Bui. 97, p. G. 



c Compiled analyses by Van Slyke, New York Agr. Exper. Sta. Bui. 258, p. 449. 

 [Cir.5l] 



