]o Jan., 1911-] Sulphitittg. 27 



The action of sulphurous acid does not merely concern fermentation, ceasing 

 when the vats are racked. It continues long after ; one can truly saj' that it 

 dominates wine-making and the keeping of the wine. 



Being {)ractically sterilized, the wine is henceforth protected from all damage, 

 either by oxydase (casse) or bacteria. One need no longer consider delicate, 

 costly and insufficient treatments for faults or diseases. 



Ordinary cellar processes are considerably simplified ; besides usual 

 care of casks (cleanliness, &c.), they are reduced to little more than filling up 

 and racking. Filtration and fining, in a thoroughly brilliant wine, become unneces- 

 sary. The latter operation is limited to correction of excessive astringency in 

 rough or deeply coloured wines. 



Sulphurous acid has already powerfully contributed to the improve- 

 ment of wine-making practice, hitherto so slow to take advantage of the teaching 

 oenological science owes to Pasteur and his disciples. 



One is compelled to admit that it is especially since its use has 

 become common in the shape of the addition of sulphites to the crushed grapes, 

 that the number of badly made, faulty or sick wines, formerly so common, has 

 considerably diminished. Such wines have almost disappeared from the trade, 

 on which they proved such a heavy burden only a few years ago, and to which 

 Ihey did so much harm in keeping down prices. 



Further recommendation is surelv unnecessary ! 



Different Forms of SO^ and Dose to Use. 



There are four main forms in which suphurous acid may be applied to 

 the crushed grapes : — 



1. In the gaseous state. 



2. Liquified under pressure. 



3. Dissolved in water. 



4. Combined with a base as sulphite or bisulphite. 



So far as attainment of the result desired there is little or no difference 

 between these four forms, provided, of course, that they be used in such 

 quantities that an equal amount of sulphurous acid be added in each case. 



The first has been generally abandoned, owing to the difficulty of 

 gauging the quantity used with anything like accuracy. For further par- 

 ticulars see Roos' Wine-making in Hot Climates, where different ap- 

 pliances by which must or wine can be made to absorb it are described. 



Liquified under a pressure of 3 atmospheres the above objections no 

 longer hold good, especially when the the ingenious measuring devices re- 

 cently placed on the market in France are employed. The.se have not yet 

 found their way to Australia, however. 



The sulphurous acid of commerce, a simple solution of the gas in 

 water, is a convenient form to use. Its usual strength is 9 per cent, of 

 SO.j. The chief drawback is the ease with which the dissolved gas is 

 given off and strength lost unless it is kept tightly corked ; it is also liable 

 to oxidation into sulphuric acid, if kept for any lengtli of time. Its 

 strength is thus apt to vary a good deal ; this is, in fact, its main defect. 

 The trifling addition of water which its use entails, though sometimes 

 looked upon as an objection, is too slight to merit serious notice. If 

 freshly made and kept tightly corked it is a satisfactory form. 



The combined form is, on the whole, the most convenient. Several 

 sulpliites ;in(l t.isiil|)hites exist, but it is in the form of bisulphite of 

 jK)tash that it is most generally applied in France. Potash is by far 

 ;he most satisfactory base. After combination with the tartaric acid of 

 the grape it forms cream of tartar, a natural constituent of all sound 

 wines and oik \vlii( h, if in excess, is simply precipitated as argol or wine- 

 stone 



