' ' The analysis of grapes shows us that the
chief ingredient in their juice is glucose, a kind
of sugar. There is also some albuminoid matter
and a little tartaric acid, chiefly in combination
with potash ; other minor ingredients also exist
in grape-juice. The seeds of the grape contain
the astringent substance, tannin, with some
bitter principles, while in the skins not onlj-
does colouring matter exist, but also some flavour-
ing matters and tannin. From these facts it
will be clearly seen that very different qualities
of wine may be made from the same quality of
grape, according to the method of operating
upon the fruit. The colour, the bouquet or
volatile flavour, the astringency, &c., of a wine
may thus be varied according to the admission or
exclusion of the characteristic ingredients of the
skins and stones of the grapes.
"The main difference between grape-juice
and grape- wine is the substitution of the sugar
in the former by the alcohol which is charac-
teristic of the latter. But other changes occur in
the fermentation and ripening of wine. Much
of the acid tartrate of potash is deposited from
the liquid on being kept, this deposit being called
argol. Argol consists chiefly of the above-
mentioned tartrate, but with it a little colouring
matter and some tartrate of lime are always
found. In the stronger but natural white wines
small floating crystals of cream of tartar often
occur; they are nearly pure acid tartrate of
potash. A smaU quantity of free acetic acid is
found in wines. \Vhen they become sour it is
this acid to which the sourness is due; it is
formed by the oxidation of some of the alcohol
present, a change which occurs more readily in
weak natural wines than in those which contain
much alcohol. Another important characteristic
of wines is the presence in small quantity of
certain compounds called ethers. They are
usually fragrant oily liquids, of which traces
are present in all wines. These ethers are com-
pounds formed by the union of the ordinary
alcohol or spirit of wine with some of the acids
which are contained in the fermented liquor — at
least this is usually the case. Much, then, of
the flavour and perfume of a wine is due to
these ethers, some of which existed, ready-
formed, in the grape itself, while others were
slowly formed in keeping the fermented liquor.
Different varieties of grape yield differentlj'-
flavoured wines, but the alcoholic strength of a
wine depends mainly upon the proportion of
sugar in the grapes, and in the degree of com-
pletion to which the process of fermentation is
carried. The same kind of grape gives a very
different wine as to flavour and alcoholic strength
in accordance with the cliniate in which it is
grown, the season, and the soil.
"The quantity of true or absolute alcohol in
natural wines varies from 7 per cent, in some
hocks, clarets, and other light wines, to 13 per
cent, in many Greek and Hungarian vintages.
When the quantity of absolute alcohol exceeds
13 or 13^ per cent, it may usually be c<)nsidered
WIN
( 1139 )
WIN
Page 2311
Presented as published in 1892. Historical recipes may not meet modern food-safety standards. Cook from the modern interpretation, not the original instructions.
AI-modernized reading of the original text
' ' The analysis of grapes shows us that the chief ingredient in their juice is glucose, a kind of sugar. There is also some albuminoid matter and a little tartaric acid, chiefly in combination with potash ; other minor ingredients also exist in grape-juice. The seeds of the grape contain the astringent substance, tannin, with some bitter principles, while in the skins not only does colouring matter exist, but also some flavouring matters and tannin. From these facts it will be clearly seen that very different qualities of wine may be made from the same quality of grape, according to the method of operating upon the fruit. The colour, the bouquet or volatile flavour, the astringency, &c., of a wine may thus be varied according to the admission or exclusion of the characteristic ingredients of the skins and stones of the grapes.
"The main difference between grape-juice and grape- wine is the substitution of the sugar in the former by the alcohol which is characteristic of the latter. But other changes occur in the fermentation and ripening of wine. Much of the acid tartrate of potash is deposited from the liquid on being kept, this deposit being called argol. Argol consists chiefly of the abovementioned tartrate, but with it a little colouring matter and some tartrate of lime are always found. In the stronger but natural white wines small floating crystals of cream of tartar often occur; they are nearly pure acid tartrate of potash. A smaU quantity of free acetic acid is found in wines. \Vhen they become sour it is this acid to which the sourness is due; it is formed by the oxidation of some of the alcohol present, a change which occurs more readily in weak natural wines than in those which contain much alcohol. Another important characteristic of wines is the presence in small quantity of certain compounds called ethers. They are usually fragrant oily liquids, of which traces are present in all wines. These ethers are compounds formed by the union of the ordinary alcohol or spirit of wine with some of the acids which are contained in the fermented liquor — at least this is usually the case. Much, then, of the flavour and perfume of a wine is due to these ethers, some of which existed, readyformed, in the grape itself, while others were slowly formed in keeping the fermented liquor. Different varieties of grape yield differently- flavoured wines, but the alcoholic strength of a wine depends mainly upon the proportion of sugar in the grapes, and in the degree of completion to which the process of fermentation is carried. The same kind of grape gives a very different wine as to flavour and alcoholic strength in accordance with the cliniate in which it is grown, the season, and the soil.
"The quantity of true or absolute alcohol in natural wines varies from 7 per cent, in some hocks, clarets, and other light wines, to 13 per cent, in many Greek and Hungarian vintages. When the quantity of absolute alcohol exceeds 13 or 13^ per cent, it may usually be considered
WIN
( 1139 )
WIN