288 APPENDIX. 
which we have laid down, and never to depart from the perfection of 
detail which is suggested by practice. 
The ferment to make use of admits of certain discrimination ; for, 
although it may be proved that the juice of the sorgho maintains its 
fermentable principles in itself, as its action is too weak, it is 
indispensable to hasten it by artificial means. Brewers’ yeast, which 
is made use of commonly, has the fault of often giving a bad taste to 
the products arising from distillation, an effect which is lessened, 
it is true, by a continuous system; but the juice of the sorgho, as we 
learn from M. Pezery, reproduces a large quantity of yellowish 
ferment, presenting a great analogy to the yeast of beer in the form 
of its globules, and possessing also the same stimulating properties. 
Here, then, we have a ferment already to our hand, which may be 
made use of, not only for its legitimate end, but the surplus of which 
can be profitably used by bakers. We cannot conclude our notice of 
the matters which relate to the fermentation, without saying a word 
upon the use of sulphuric acid. It is well understood to-day, that the 
addition of this acid in the proportion of one half thousandth part to 
one and a half thousandth parts, favors the transformation of the 
sugar into glucose,* and prevents the viscous fermentation. This last 
property should be taken into consideration, when, at the end of the 
season, we have upon our hands only canes which are more or less 
damaged, one is obliged to operate upon juices of which the fermen- 
tation is irregular, and sometimes causes very prejudicial accidents. 
Finally, experience has proved that the residues of fermentation, 
where the sulphuric acid is employed, are more profitable for cattle. 
Let us remark further, with M. Beaudement,t that all fermentation 
cannot be carried on without acid or its equivalent ; if it is not put in, 
it forms itself at the expense of the sugar and of the alcohol; and so 
positive is this, that the fermentations made without the addition of 
acid are more acid at the end than those where it has been added. 
The sugar of the juice having been changed into alcohol, it is neces- 
* M. Du Bronfaut, who since 1825 has known this influence, apprises us also that 
the acids have a favorable action upon the reproduction of an energetic yeast, capable 
of being used in the other fermentations of juices. 
+ Report upon the Beet Distilleries, 1855 and 1856, made to a Commission of the 
Society of Agriculture, by M. Beaudement, p. 58. 
