The morning call., 1890-11-08
PRESERVATIVE FLUIDS.
Various Methods Explained for Treating
Fresh Fruits.

WASHINGTON, Nov. THE experiment
station record for October was issued to-day
by the Agricultural Department. 1t con-
tains an extract from an article on "PreServ-
alive Fluids for Fresh Fruits by e. F.
Hilgard, Ph.D. This article was written in
answer to inquiries regarding the method OF
preserving the samples of fruit for exhibit
tion at fairs. In general, the preservative
must be an antiseptic liquid, which will
neither exercise solvent or softening action
upon the fruit, nor extract nor change its
color, nor differ SO in density from tine juices
of the fruit as to cause the latter to shrink
or swell. Alcohol, sugar, glycerlne and
salt, while useful as a preServative, for
some purposes do not meet all these condi-
tions.
Salcylic acid, boracic acid, sulphurous
acid and biSulphite of soda are recommended
as antiseptcs and the methods of their use
described. Attention is called 10 the results
of Investigations by Professor Pichi of the
Royal Niticultural School at Coneg lianO,
Italy, with corrosive sublimate (bichlOride
OF mercury for the preservation of grapes.
Professor Pichfs conclusion is: That
grapes in punches can best be preserved for
collections by keeping them Immersed in
solution of corrosive sublimatt, taking espe-
cial care TO wash them thoroughly before
hand. The best strength for this solution
seems to te pro mile. The poisonous ma
tuic VI luls uuiu SHOulu Dt ldhcu lnto dC-
count Tests OF this preservalive are now
in progress at the California station.
The "Sulphuring Of Dried Fruits" by
Professor Hilgard, is resume of the
authors opinion on this subject, which is
OF considerable Importance III California
The sulphnrlng Of dried fruit has two OBJ
jectS-to brighten the color and to prevent
the attacks OF insects. When freshly sliced
fruit is heated with sulphurous acid for
short time the effe t on fruit is compara-
lively slight. and yet insects are toa con-
siderable extent deferred from touching
such fruit. When, however, as is often the
case. fruit Is thoroughly sulphured after
drying, the gas penetrates the entire sp0ngy
mass Of fruit, bleaching II without regard
to its quality, injuring It's flavor. and, worst
OF all, causing the formation of sulphuric
acid in sufficient amount TO be Injurious to
health.
This las. point is enforced by statements
of ar analysis Of sulphured apricots and
prunes, in which specimen Of the former
fruit was shown to contain 2.32 per cent of
Sulphuric acid equivalent to about twenty
five grains of oil of vitrioD per pound aud
the latter SAC per cent OF sulphuric acid,
mostly free"
In most European countries the sale of
Sulpbured fruit is forbidden. California
fruitgrowers are advised to make an effort
to educate the public taste SO that 1t will
prefer healthy, brown, nigh favored fruit
to the sickly, chemical tinted product of the
sulphur box.
Professor Hilgard also issues bulletin
on the conservation Of wines. This bulletin
was prepared to combat irrational preju-
dice against the treatment of wines by
purely physical means, Sucn as are com-
monty employed in wine-producing coun-
tries of Europe, especially in those in
which the prevalence of climati conditions
similar to ours renders the conservation of
dry wines not fortified matter of well-rec-
ognLed and acknowledged difficulty. The
process OF wine heating, or pasteuriZlng,
direct treatment with an electric current,
and the sterilization OF wine by filtration
through porous porcelain are described and
discussed, principally by means OF quota
tons from foreign sources. An electro-mag-
netic process, devised by DR.. Fraser of San
Francisco, is also favorably referred to.