SULPHUROUS ACID AND SULPHITES. Y63 



if the wines become entirely saturated with sulphurous acid the sec- 

 ondary fermentations which produce the ripening of the wine would 

 not take place. In such cases the wines apparently appear to be 

 perfectly mature within one or two years, whereas the proper matura- 

 tion of a wine requires a much longer time. In the manufacture of 

 non-fortified sweet wines much larger amounts of sulphur are used 

 than in the manufacture of dry wines. This is an important fact, 

 since it shows that the large quantities of sulphur are not necessary 

 for the preservation of dry wines, because it is well known that red 

 wines, which are generally very dry, are quite as well preserved as 

 white, although containing much less sulphurous acid. It is claimed 

 that in the manufacture of sweet wines that is, those in which the 

 natural sugars coming from the juice of the grape are not entirely 

 fermented larger quantities of sulphur are necessary to prevent 

 fermentations after the wine is mature. If the sweet wine be made 

 from a suitable kind of grape that is, one which is so rich in sugar 

 that it gives a certain maximum quantity of alcohol and still leaves 

 some unfermented sugar it is evident that no excess of sulphurous 

 acid will be necessary. In such a case the wine would be preserved 

 by its natural alcoholic content. If, on the other hand, a sweet wine 

 be made from a must so poor in sugar that it is necessary to add an 

 additional quantity, the product can not be regarded as a natural 

 wine, and hence there seems to be no necessity for providing for 

 its manufacture. 



In the. manufacture of sirups and molasses it is quite customary 

 to expose the freshly expressed juices of the canes to the fumes of 

 burning sulphur. The " sulphur box" used in this case is so con- 

 structed that the juice falling over shelves by gravity absorbs the 

 fumes of the burning sulphur rising from the box, which to this 

 extent serves as a chimney. The sulphur dioxid becomes incorpo- 

 rated with the components of the juice forming more or less stable 

 compounds which are not entirely broken up by subsequent boiling. 

 The sulphur in this form, as well as that which may still be present 

 in the free state (that is either as an absorbed gas or in combination 

 with metallic bases), passes into. the finished product. When sugar 

 is made there is a concentration of the sulphur compounds in the 

 molasses and this concentration 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 quan- 

 tities. 



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

 mandarins 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 overlooked in trimming. 



(3) To prevent fermentation and decay during the drying of the fruit. 



