Evening star. [volume] (Washington, D.C.) 1854-1972, 1877-12-29

MAGNITUDE or THE BUSINESS on IRE pr

MAGNITUDE or THE BUSINESS on RE della
WARE PENINSULA.
letter from Harrington. Del, 10 the vii
mington Enery EstRfaq, says.
The magnitude of the fIi.f evapora'ing
interest can he coniecfured when IL is stated
that not less than there hundred fruit presery.
ing Establishments are locaied on this PENN
sula. With the number rapidly increasing.
There are three methods of removing the
natural juices from fruit-sun drying, kiln, or
oItn Crying, aud cooperating.
The method OF drying in the sun is well
known. Kiln or oven drying il better than
sun driving. as the operation is more rapid.
The nut also u kept from the action of neS,
81 numerous during the fruit season. aud
much less liable In &c infested with worms.
Many of our dryers are only large ovens or
the action Of heat. BY this method the surface
is first dried-nearly eharred-wsile the inner
portion of fruit is soft. When pressed together
the moisture from within u absorbed by the
charrtd surface, and when not oyer-charred
the pieces of fuit all become soft and plant.
Evaporation il based ON entirely different
principles. The surface i Kept moist while
the entire process Is going on, whether the
evaporation is in n hot-air chamber or in
melted sugar. When the evaporation of the
natural juices is effected i'm melted sugar.
the process however, II usually called con-
serving
Evaporation i'm a moist hot air chamber is
based upon the We'll known scientific fact that
volume of air at the freezing point absorbs
the one hundred and siNtieth part only Of it,
own weight of moisture. and that every
doubles its absorbing power. Hence. il air NJ
thirfy-two degrees Fah- the freezing point,
ahsorbs the one hundred aud siNtieth of it,
own weight Of moisture, at ffty-nine degrees
Fah il win absorb the one eightieth of its own
weight of moisture; and at eighty-siN degrees
Fab. the one-fortieth: and M one hundred and
thirteen degrees Fab. the one twentieth; and
at one hundred and forty degrees Fab. the
onetenih: and at one hundred and sixty
seven degrees the one NTH; and at one-hun-
dred aud ninety-four degrees the two-ifths /:
81 nHaA Al 80
Fab. the four -hfths, or nearly siis own weight.
while at two hundred and f0rty-eight degrees
Eah., heated air viii absorb one and three
flths its own weight of moisture.
Now. put this heated body of air. charged
with more than its own weight of moisture.
in motion AT the rate of twenty miles an hour.
or eight hundred an eighty feet per minute.
aud the reason oi eyaporating fruit 30 rapidly
i apparent. Every one hundred cubic inches
oi air AT sixty degrees Fab and thirty inches
Ia the barometer contains about thirty grains
of water. and AT two hundred and twelve de-
grecS Fab. not far from one fourth of am ounce
oi wafer dryer chamber Oi the capacity ~
TWO hundred and twenty five cubic feet. ac-
cordlng To this estimate, will contain al a tenn
perature of two hundred and twelve degrees
Fab. July sixty pounds of water, fifty pounds
OF WHICH as been absorbed from the heated
fruit. II the circulation il sufficient To empty
this chamber every twenty minutes. one hun
drtd and nifty pounds of water il abstractcd
and carried away from a dryer fun of fruit
weighing eight hundred pounds every hour or
seven hundred and fifty pounds are carried of
in five hours. about the time necessary 10
eNaporate apples or peaches when in good con
dition.
Ii viii he seen from this that heat alone is
not suf1iclent To produce evaporation. Ii Will
not do n, however great either on the earth
or i'm an evaporator. stormy winds fulfill the
pleasure of the Creator quite as eflectualy i'm
drying up the surface of the earth after a
heavy rain as do the burning rays of the sun.
The sun $ heat alone on the moist earth would
NIL the air with dense. damp yapor. deStruc-
tive alike To the health OF animals and plants.
SO, in tie philosophical dryer. the fruit is put
IN AT the bottom OF heated air chamber. where
a stream of cold air containing the fortieth
part uf its weight of moisture IL introduced
and driven through the fruit at the rate of
twenty miles an hour, and out OF an escape
loaded with more than its own weight of
moisture. The air I'm motion more than the
heat causes the fruit to dry rapidly. and the
rapidlty of the process and the moisture in
which The fruit Is enveloped prevent GNda-
ton, or decay. and gives the evaporated fruit
When net oyer-rlpe, 80 mnch of the color of
fresh fruit The shorter the time the fruit is
In the dryer. the more perfectly the oxygen is
excluded. the brighter the color.
But tie color OF the fruit. however strongly
II may recommend il To the consumers. Is by
lar the least practical benefit in the process of
evaporation. The nutritiye value of evap-
GRATED fruit in consequence IF the chemical
changes during the process of lis chief recon-
mendation.
1t is still an open question whether the RAPID
change OF starch into grape sugar i'm the moist
hot-alr chamber of philosophical evaporation
may not he attended by the further change of
oil grape into cane sugar. though no actual
analysis demonstrating the fact has yet been
made.
Crystals of sugar exist often in great album
dance on the surface of well-prepared speci-
mems of eNapOrated peaches and pears. and
possibly on apples. though have not observed
NJ. III certainly lakes much less sugar 10 suit
ably sweeten evaporated than sun or kiln
dried fruit OF any Kind.