centration becomes greater in proportion to the number of crops of 

 sugar crystals removed. In very low grade molasses the sulphur 

 naturally occurs in extraordinarily large quantities. 



In the preparation of evaporated apricots, peaches, pears, and man- 

 darins sulphuring is practiced for the following reasons : 



1. To produce as clear and intense a yellow color as possible. 



2. To conceal decayed portions of the fruit which have been over- 

 looked in trimming. 



3. To prevent fermentation and decay during the drying of {he 

 fruit. 



4. To protect the fruit during drying from flies and other insects 

 the larva? of which would otherwise develop after the fruit was 

 stored. 



5. To kill the cells of the fruit and thus make the texture more 

 porous, which expedites drying. 



In the application of the fumes of burning sulphur in the prepara- 

 tion of evaporated apples the principal object appears to be the pres- 

 ervation of the color of the finished product. Fruits which have been 

 sulphured before evaporation seem to have a lighter color than 

 those which are dried without sulphuring. At the same time it is 

 well known that highly sulphured fruits are preserved with a lower 

 degree of desiccation than those not sulphured, and for this reason 

 a greater weight of fruit is produced from a given weight of the raw 

 material when sulphur is used. It is not difficult to preserve a water 

 content of 30 per cent or over in the finished product when liberal 

 sulphuring is practiced. The use of sulphurous acid also makes it 

 easier to protect the finished product from mold and fungous growths 

 in general after manufacture. That excessive quantities of sulphur 

 are not necessary for the production of evaporated fruits of pleasing 

 appearance is well attested by analytical data obtained by the exam- 

 ination of fruits purchased in the open market having a light and 

 pleasing color and at the same time containing only a small quantity 

 of sulphurous acid. On the other hand, it is quite easy by certain 

 forms of treatment during the process of manufacture to obtain a 

 product in which sulphurous acid is present in excessively large 

 quantities. The analytical data also show that a portion of the 

 sulphurous acid used in the preparation of such products becomes 

 oxidized into sulphuric acid after a certain time, thus artificially 

 increasing the small amount of sulphates naturally present in some 

 food products, which does not appear to be a desirable practice. 



As sulphurous acid in some form is almost universally employed in 

 the manufacture of wines, molasses, and sirups, and in the prepara- 



[Cir. 37] 



