SOUTHERN CULTIVATOR 
275 
this proportion varies according to the climate, the matur- 
ity and quality of the grapes. 
The constituent principles of spirituon.s fermentation, 
Vv'heii known by their real nauiCa, oy ihcir dit>!ii)clive ; 
characters, and their properties, will tlirow a great lis'ht | 
on the phenomena of this kind of ftrmetitation, atid on the i 
means of directing and ohtaining the best wines. ' 
INFLUENCE OF THE CONSTITUENT miN'CirLES OF MUST ON FEK- j 
.MENTATION. | 
Water; Tartar; tJie nuicoso-s.accharine matter ami i 
sugar, are the constituent principles of Must. j 
Spirituous fermentation is the result of the decomposi- ' 
tion of these four principles. 
The diflerence in the product of fermentation arises from 
the different proportions of these principles. 
There are seasons when nature unites in a just propor- 
tion the principles which form wine of an excellent qual- 
ity; agreeable, generous, and susceptible of preservation ; 
but they seldom happen. 
There are years on the contrary, and they are by far 
the most numerous, when rains, drought, cold and prema- 
ture frosts, prevent the grape from coming to rr.aturity. 
In these cases the Must is too watery; there is too little 
mucoso-saccharine matter and sugar, and bad wine is pro- 
duced from it. This disproportion wc can easily remedy, 
having tartar, the mucoso-saccharine matter, and sugar at 
our disposal, especially sugar, which is always the same 
substance, from whatever body extracted. 
EXPERIMENT, (f) 
500 quarts of Musi* having gone through the fermenta- 
tion process, have yielded by distillation one-twelfth part 
of alcohol or brandy, of 20 degrees proof;! quarts of 
similar Must with the addition of four pounds of tartar and 
ten pounds of sugar, having undergone the sanfe process, 
yielded one-fifth part of alcohol of equal strength. In the 
second case, the fermentation lasted 48 hours longer. From 
this experiment it will be perceived that sweet grapes re- 
quire an addition of tartar, as it promotes the conversion 
of sugar into alcohol. 
The vinous fermentation is influenced by several cir- 
cumstances, such as temperature, air, and the volume of | 
the Must. ! 
or AIR, ' 
The presence of air is not absolutely necessary to excite i 
fermentation, A fermenting body, deprived of air can j 
with difficulty be impeded in its progress, especially if it j 
be exposed to a warm temperature ; it ferments slowly, j 
and produces a spirituous liquor so much the better, as it ■ 
does not lose by evaporation any of those principles j 
which contribute to the excellence of wine, a part of which | 
would be destroyed by a violent fermentation. 8uch a 
wine has lost none of its arom.a, flavor, or any of its alco- 
hol. Thus, the privation of air confines only for a while 
the principles of must; as soon as air is admitted into it, | 
these principles disunite and decompose, but quickly unite j 
and recompose again to form a spirituous liquor. — j 
The concurrence of airi.s, therefore, useful to fermentation j 
as it makes it puss through its difterent periods in a given j 
lime. External air is not absorbed by the fermenting [ 
body, as it happens in many other operations of nature; 
fijr example : in acetification— it acts mechanically and 
facilitates the escape of the gasses formed by fermentation. I 
These gasses spread in the atmosphere, are carried off 
and dissipated. Under this point of view, air impoverish- 
es the fermenting body by favoring volatilization — the 
gas, when retained in the liquid, combines with it, and 
improves the wine. The means of retaining more of the 
evaporating elements, in a fermenting liquid, without re- ! 
larding fermentation, would be solving a gre^and useful i 
problem. A cover made to fit tlic inside of the vat and 
loaded with weights, so as to rise and fall by the dilation 
and sinking of the bulk, would surely produce that effect ; 
ii would u!*o preveiil air aciuig ua the surface of ihei 
vintage, and produemg acidity* and mouldiness, which 
charge die quality of tiie wliole vaf, when penetrates 
the. liquid— the pressed wine would tlien d'ffcv but httlc 
from that obtained in the vat. 
OF HEAT. 
It is necessary* to h.ave a thermometer in the rraiiufac- 
tory, to ascertain the temperature of the atmosphere, and 
the degrees of heat in the vat when the Must is fermenting 
—below 55 degrees of the thermometer, the must does not 
ferment, or does .so badly. Thus the favorable tempera- 
ture is 55 deg., below that, it lingers; above, it becomes 
loo violent. Spirituous fermentation does not take place 
in too cold or too warm a temperature ; must put in ves- 
sels well stopped, and sunlc in a river or a well, will pre- 
serve its sweetness ; cold and the privation of air are, 
then, causes opposed to fermentation. The colder the 
temperature is the slower the fermentation will be : there- 
fore, it is recommended to make the vintage in warm 
weather, or to expose the grapes to the sun before they 
are put in the vat. If the fermentative process be retarded 
by cold, the must should bestirred; this motion excites 
heat, and disposes the constituent principles of the mustto 
action and disunion — a fire should be made in the manu- 
factory and the vat covered with thick clotlia; part of the 
must is then boiled and poured into the mass ; the heat 
will immediately spread and follow fermentation to its end. 
When the fermentation is not violent, the heat is unequal- 
ly spread, and its intensity is more central — to produce 
an equal temperature, the vintage is trodden and stirred ; 
this operation is performed by means of rakes with long 
handles. The laborer should be placed outside of the vat 
and raised several feet above its level, so as not to be af- 
fected by the gas floating over the fermenting matter. It 
would be extremely imprudent to go into the vat to tread 
or stir the bulk ; many laborers, from want of caution, be- 
come victims of this gas. The agitation in the vat should 
not bo of long continuance, for fear of losing a large quan- 
tity of the gas, which essentially contributes to the mak- 
ing of wine. 
or THE, BULK. 
The heat oftiie Inilk is in porportion toils volume; the 
heat is greater in a large mass, because the motion is more 
considerable. Moreover, the presence of the sten.T, of tlie 
skin, and of the grape stones, increases the activity offer- 
mentation. When the fermentation is violent, particular- 
ly in a large bulk, the heat causes the thermometer to rise 
from 59“ to 95“. 
SIGNS ACCOMPANYING FERMENTATION, (>) 
These signs are bubbles on the surface of the liquor — 
soon after other bubbles rise from the centre to the surface ; 
their passage through the agitated liquid produces a hiss- 
ing, resembling the noise of a slight ebulition — drops of 
the liquid rise and fall; the liquor becomes muddy; every 
thing bears the appearance of confusion ; filaments, flakes, 
skins, grape-stones and grapes float indiscriminately, are 
pushed and driven about until a part is precipitated to the 
bottom of the vat, whilst the other remains on the surface 
and forms what is called the cap of the vintage. The bulk 
increases — the bubbles escape through the cap, producing 
a great deal of foam. The heat increases in proportion to 
the strength of the fermentation — the fermenting mass 
causes the mercury to rise to 95 degrees, when it is not 
higher than 55“ in a common exposure. The sign accom- 
panying this violent fermentation decreases after several 
days, and sometimes after a few hours, the bulk resumes 
'Of what specific gravity ? 
i What was the specific gravity > 
tCbapeau fie la Venfiaugc- 
§Tlie chapeau or cap .sinks. 
