Allen Paul W. Industrial Fermentations
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FOOD PRESERVATION PROCESSES 231
sour rniiv or vinegar axe sometimes added to the cabbage as it is
prepared to insure proper fermentation.
According to Lipman, the bacterial activities in sauerkraut making
are twofold, that is, flavor production, and the prevention of putre-
faction for a period of time. The juices of lie cabbage, due to
pressure and the presence of the salt, flow out of the tissues and create
a medium in which many varieties of acid and gas producing bacteria
develop rapidly, evolving considerable gas and increasing the laotio
aoid content of the liquor. Finally a membrane covers the surface of
the liquor formed by Oidium lactis. Yeasts are also active in the
liquor attacking the sugars which have diffused from the cabbage.
' The action of yeasts in converting the sugars into alcohol and CO
a
and the lactic acid bacteria converting the sugars into, lactic acid
develop some sort of associative action according to some bacteri-
ologists.
The commercial method of manufacture of sauerkraut according
to A. W. Bitting is as follows:
"Sauerkraut is made by the natural fermentation of cabbage in
casks.
The cabbage heads are stripped of all outside or green leaves,
leaving only the white sound head. It is then cut into thin slices
in a specially constructed machine. The long, fine-cut cabbage is
evenly spread and well packed in casks. To each layer salt is added
at the rate of about 2 pounds per 100 pounds of cabbage. The salt i&
used as flavoring and to modify in some degree the fermentation.
If too much salt is used, a pinkish color results; if too little, the
fermented product may become more or less slimy. The temperature
of the weather at the time of putting up the cabbage also influences
the fermentation. If the weatner is very warm, the fermentation is
too rapid, the product has a very white but more or-less slimy ap-
pearance, and the cabbage is tough rather than of a natural crispness.
If the temperature is very low, fermentation will be arrested. The
best temperature is probably between 60 degrees and 70 degrees F.
and the process requires
1
about 4 weeks. Fermentation begins as soon
as the cabbage is placed in the cask, but there iB only a slight rise of
temperature as compared with most fermentation processes. A heavy
foam rises to the top, which must be skimmed off every day, and when
this ceases to form the brine goes
1
down and the process is complete.
Use can be made of the kraut at once, though it seems to be better
after standing. The kraut will keep in the casks for a long time,
provided there is no leakage, and the spoilage is usually limited to a
few inches on the top.
"Kraut is easily canned, which is the only clean way of dispensing
it in groceries in small quantities. The oanning should be done where
the kraut is made. The shipping of kraut in barrels to distant points
to be canned has nothing to commend it and much to condemn it.
The repacking in barrels means labor and loss of material, and in
too many cases the loss of natural brine, after which spoilage takes
place easily. The canning should be done while it is in the freshest
232 INDUSTRIAL FERMENTATIONS
possible state at the point of production. Kraut is easily kept. The
cana should be filled full, weighed, and sufficient hot water added
to fill the can; then exhausted, capped and processed at boiling tem-
perature for 26 minutes.
"The gases evolved in sauerkraut are mainly carbon dioxide, and
hydrogen. The organic acids, succinio acid, acetic acid in addition to
lactic acid are formed. However, lactic acid is
1
the main acid formed.
Dill Pickles.
"The process of making dill pickles does not differ much from
that of making sauerkraut as far as the fermentation is concerned.
The sugars of the cucumbers diffuse out of the cut cucumbers into
the liquor and are fermented by lactic acid bacteria and alcoholic
yeasts. As in sauerkraut, B. coli communis and allied bacteria are
active fermenters producing hydrogen and carbon dioxide. Oidium
lactic finally grows on the surface of the liquor and reduces the
acidity.
"Sound cucumbers are used in the manufacture of dill pickles.
They are placed in layers with dill stalks, leaves, and seeds in wooden
tanks or in earthenware. A brine liquor composed of 10% salt, 15%
vinegar and 75% water is placed over the cucumbers.
"Dill pickles, which are much prized and command the highest
price among pickles, can be made from fresh cucumbers as
1
they
come from the vines, or from vat stock which has been carried for
some time at the salting station.
"Dill pickles from fresh cucumbers are of high quality, but not
quite as satisfactory keepers as when made from salt stock. In
preparing fresh stock for dill purposes, fresh cucumbers as they come
from the field are placed in wine casks from which one head has been
removed. A layer of piokled dill and one quart of dill spice is placed
at the bottom of the barrel. The cucumbers should be assorted care-
fully as to size, one grade of about 4 inches in length being placed in
one receptacle and another grade of 5 inches in length, or approxi-
mately this length, in another barrel. After a cask has been filled,
a layer of dill is placed over the fruits before the head is replaced.
After the cask has been reheaded, the commercial practice is to
remove the bung and fill the cask containing cucumbers with a 45
degree Baum6 test brine, adding one pound of porous alum to each
46 gallons of brine. The cucumbers are left in this brine five days.
The first brine is then replaced by a thirty degree brine, to each
forty gallons of which one-half pound of porous alum and 4 gallons of
80-grain vinegar are added, the whole heated to 160 degrees F. before
being placed in casks.
"To make dill pickles from salt stock, the cuoumbers are removed
from the brine, placed in a processing tank and covered with fresh
cold water, and allowed to remain twenty-four hours, after whioh
the water is drawn off. The tank is then again filled with fresh water
FOOD PRESERVATION PROCESSES 233
to which are added 2 pounds of alum and two ounces of turmeric to
each barrel of pickles in the tank The whole mass is then heated up
slowly to 130 degrees F. The fruits are allowed to stand in this cooling
mixture for twelve hours, when they are sorted and packed.
"Before beginning to fill the cask with cucumbers, place a layer of
pickled dill herb at the bottom of the cask, fill the cask half full of
processed cucumbers, and add another layer of dill herb, at the same
time placing in the cask one quart of dill spice, consisting of the follow-
ing proportions of whole spices: 4 pounds of allspice, 2 pounds of
arushed black pepper, 4 pounds of coriander seed, and one pound of bay
leaves. After adding this spice and the layer of dill herb, complete the
Sliing of the cask, but before replacing the head of the cask scatter
mother layer of dill herb over the cucumbers. After being reheaded,
die bung is removed and the cask filled with dill brine consisting of
ine-fourth barrel of dill herb, V/% pounds of alum, and 100 gallons of
JO degree brine. At the time of filling the barrel one gallon of 50
grain vinegar is added to each 10 gallons of the brine. This brine
ihould be allowed to stand twenty-four hours before using it to cover
.he processed ououmbers packed in barrels, as above desoribed.
The Salting Station.
"The gathering points or receiving depots maintained by pickle
actories in communities where cucumbers are commercially grown are
ailed salting stations. The equipment of the salting station oonsists
f a long, low building provided with a large number of wooden tanks,
common size of which is ten feet in depth and sixteen feet in diameter,
nth a capacity of about 1,500 bushels. An ordinary salting station
all contain forty of these tanks, haying a capacity of 60,000 bushels.
"The cucumbers as they are received from the farmers, if of com-
aratively uniform size, are dumped direotly from the receptaoles in
r
hich they are delivered into the vats, the vats being first provided to
le depth of 12 to 18 inches with seventy degrees to eighty degrees
>aum€ brine, which is made by adding 2 pounds of salt to each gallon
f water. As cucumbers are added 100 pounds of salt are scattered
ver the fruits for each thousand pounds of cucumbers which means
pproximately about 5 pounds of salt to each bushel of cucumbers.
: it requires more than a single day to fill the tank a quantity of
ilt should be scattered over the cucumbers before suspending work
b night, and if it is to be carried over Sunday or a holiday the
lcumbers should be salted and pressed under lie brine from time
* time during the interval the work is suspended. This will keep the
icumbers from getting soft and becoming yellow. If the tank is not
to large and a false head can be employed this will serve to hold the
icumbers under the brine. In large tanks this is a troublesome
•ocess,
and the customary means of protecting them is to push them
ider the brine with a suitable paddle.
"After the tank is full of cucumbers and before the false head has
234
INDUSTRIAL FERMENTATIONS
been put in place, the weight of the cucumbers in the tank should be
estimated and one pound of salt added for each hundred pounds of
fruit. A part of this Bait can be placed on top of the cover and the
tank then filled with fresh water until the liquid stands 4 to 6 inches
above the top of the cover. The salt should not be washed off the
cover by pumping water on it, but the water should be pumped into a
tube made of 6-inch boards long enough to reach from the top to the
bottom and fitted to one side of the tank, so as to carry the fresh
liquid to the bottom.
"After this additional quantity of salt has been given, the brine
After
Cool to
TIJJ3JF.
Document
90$.
Pro.
36.—The Baronovich salmon saltery; the oldest saltery in Akaka.
should test between 65 degrees and 70 degrees on Baum^'s salt scale.
After the tank has stood three or four days the top brine will have
lost strength until it has fallen to 35 degrees or 40 degrees, when 4 or
5 pounds of salt to each hundred pounds of fruit should be added.
After another period of four or five days, or as soon as the brine
falls to 45 degrees or 50 degrees, another addition of 4 pounds of salt
to each hundred pounds of fruit should be made in the way above
noted. After a week's time the brine should test about 65 or 60 degrees
at which point the cucumbers should keep well, the only additional
attention required being to pump the brine over by means of a pump
plaoed in a wooden box at the side of the tank above mentioned, every
five or six days for the first month and once in three weeks or once
FOOD PRESERVATION PROCESSES 235
a month thereafter as long as the pickles are held in the brine. The
pumping over is for the purpose of raising to the top the heavy brine
which naturally settles' to the bottom of the tank, and to cause the con-
tents of the tank to be more evenly salted.
"During the time the tank is being filled the brine is kept deep
enough to nearly cover the pickles at all times. After the tank has
been entirely filled with cucumbers—that is, heaped up with cucumbers
to a height of from 18 inches to 2 feet above the rim of the tank-
one pound of salt to each hundred pounds of cucumbers in the tank is
placed over the top layer of cucumbers, as noted above. The false
head of the tank is then put in place, stringers are laid on top of
it, and the whole is weighted with barrels of salt or other material
to force the cucumbers into the tank and beneath the surfaoe of the
brine.
''The gathering and handling of cucumbers at the salting station
involve comparatively little labor, but because the cucumbers are not
used immediately by the factories, it requires the capital invested to
be tied up for a considerable period of time.
"The fact that this salt stock can be held without material loss
for several years places the pickling industry upon a comparatively
safe basis. A crop failure in one locality in any particular year does
not, as a. rule, affect the work of the factory or change the price of
fresh stock. The reserve stored stock can be drawn upon for the needs
of the factory."
VII.
Preservation by Salting.
Many vegetables lend themselves to preservation by salt. The
most important brine preserved vegetables are cabbages, cucumbers,
peppers, cauliflower, green tomatoes, ripe tomatoes, beans, onions and
oelery. Wooden tanks or tubs of cypress or large earthenware jars
prove to be the best containers. Brines containing from 12% to 25%
or stronger are used depending upon the vegetable. The vegetables
salted should not protrude above the surface of the brine in the con-
tainer. The growth of fungi on the surface of the brine is sometimes
prevented by a film of oil or paraffin.
Small cucumbers and gherkins can be preserved by packing in
strong brine. String beans packed in layers of salt keep well but
darken slightly.
Pork is placed in strong brine and keeps well. Ducks and wild
game have similarly been salted down successfully.
VIII. Food Preservation by Spices and Essential Oils.
Foods are seldom preserved by the use of spices and products
containing essential oils, but many products are added to foods which
have a preservative effeot as cloves, cinnamon, and mustard.
Bitting describes the preparation and canning of sardines in oil as
follows: "The sardines caught on the Pacific coast'are much larger
236 INDUSTRIAL FERMENTATIONS
than those taken in the East and are handled in a different manner.
They are caught in nets at night, and on being brought to the factory
in the morning are put into bins and kept wet with running water for
some hours. They are then dressed, scaled, head and viscera removed,
and again thoroughly washed in two or more changes of water. They
are next dipped in strong salt brine for a few minutes, rinsed, and
placed in wire trays to dry. In order to expedite the drying the trays
are carried through a mechanical drier so that all surface water will
be removed. The crates are then dragged through a vat of boiling oil,
the length of time being that necessary to cook the fish thoroughly,
usually about five minutes. They are left in the crates until cool,
which is usually until the following day, placed in the cans by hand,
oil or sauce added to fill the interspaces, carefully exhausted, and
processed at 240 degrees Fahrenheit for one hour and fifteen
minutes."
F.
M. Bachmann has made a study of the use of microorganisms
to determine the preservative value of different brands of spices. The
following tables (IX and X) are from her work:
TABLE IX.
EFFECT OF DIFFBHHNT BRANDS OF CLOVBS ON BACTBBIAI. GROWTH.
Dilution Brand Brand Brand Brand
Organism of
Spice
A B C D
B.
subtilis 1:50 0 0 0 0
100 0 0 0 +
200 0 0 + +
800 0 0 + +
400 0 + + +
B.
coli 1: 50 0 0 0 0
100 0 0 0 +
200 0 + + +
800 0 + + +
400 + + + +
B.
prodigiosus 1:50 0 0 0 +
100 0 0 + +
200 0 + + +
300 + + + +
400 + + + +
Saroina lutea : 1:50 0 0 0 +
100 0 0 0 +
200 0 0 + +
800 0 + + X
400 + + + +
IX. Filtration as a Preservative Process.
The use of filtration as a preservative is not widely used but is
**«•
largely confined to laboratory media and laboratory experimen-
FOOD PRESERVATION PROCESSES
237
TABLE X.
EFFECT OF DIFFERENT BRANDS OF ALLSPICE ON THB GROWTH OF MOLDS AND YBASTS.
Dilution Brand Brand
Organism of
Spice
A B
Alternaria tenuis (?) 1: 25 0 0
50 0 0
100 0 +
Penicillium glauoum 1:25 0 0
50 0 0
100 + +
Rhizopua nigrioans ........... 1: 25 0 0
50 0 0
100 0 +
Aspergillua niger 1: 25 0 0
60 0 +
100 + +
Yeast Foam-culture from 1: 25 0 0
50 0 +
100 + +
neiflchmann'fl oompreBed-cul-
ture from 1: 25 0 0
50 0 +
100 + +
Saooharomycea cerevisiffl ...... 1: 25 0 0
50 0 +
100 + +
Saccharomyoea ellipaoideufl 1: 25 0 0
50 0 +
100 + +
Saccharomyoea anomalus 1: 25 0 0
50 0 +
100 + +
X. Food Preservation by Sealing.
Eggs are one of the most important foodB preserved by sealing.
They may be preserved in water glass. Only fresh eggs are preserved.
Water glass is composed of sodium silicate and preserves the eggs by
sealing up the pores in the shell through which baoteria normally
enter. (See chapter on Bacteriology of Eggs.)
Cheese is generally proteoted from exposure to miscellaneous or-
ganisms by sealing with paraffin. Hams also are often sealed in a
similar fashion.
XI.
Chemical Food Preservatives.
Some of the more important preservatives used in foods are ben-
zoate of soda, boric acid, salicylic acid, alcohol, formaldehyde,
sulphuric acid, potassium nitrate or saltpeter.
238 INDUSTRIAL FERMENTATIONS
Borio acid is said to be used in the butter of Australia. Benzoic
acid is used in catsup and in sweet cider to some extent in the
United States.
Preservation of Pork by Curing.
Priest in Tennessee Extension Publication No. 57, discusses the
sugar curing of pork in the following paragraphs. He says:
"Salt, saltpeter, sugar and molasses are tie principal preservatives
used in curing pork. Borax, borio acid, formalin, salicylic aoid and
other chemicals are sometimes used,, but their use
-i&
prohibited in
connection with meats and products to which the Federal meat-
inspection law is applicable and they should not be used.
After McBryds
in
U.S.D.A.
Tear Boob
1911.
Fia. 37.—Preparing corn beef for canning. Government inspector at center.
"Salt, when applied alone to meat, makes it very hard and dry,
because the aotion of the salt draws out the meat juices' and hardens
the muscle fibers. Saltpeter is used to preserve the natural color of
the meat. It is more astringent than salt and should be used sparingly.
Sugar and molasses act differently than salt. They soften the muscle
fibers and improve the flavor of the meat. The combination of salt
and sugar makes a good cure.
"Sugar cured pork is preferable to plain salt pork because of its
better flavor and because the meat is not so dry and hard. Two
ways of curing are in common use, brine curing and dry curing. Each
has its advocates. It is less trouble to pack meat in a barrel and pour
brine over it than to rub it three or four times with salt. The brine
keeps away insects and vermin. Dry curing is Bafer to use during
warm weather, and is frequently less expensive. In using either
FOOD PRESERVATION PROCESSES 239
method, rub the surface of the meat with fine salt and allow it to
drain, flesh side down, for six to twelve hours before being put in the
cure.
"Brine Curing—Make a mixture as follows for each 100 pounds
of meat:
8 pounds salt
2%
pounds sugar or syrup
2 ounces saltpeter
4 gallons water.
"In warm weather 9 to 10 pounds of salt are preferable. Allow
four days' oure for each pound in a ham or shoulder and three days
for bacon and small pieces.' For example, a 15 pound ham will take
60 days; a piece of bacon weighing 10 pounds, 30 days.
"The brine should be made the day before it is used, so that it
will be cool. All the ingredients are,poured into the water and boiled
until thoroughly mixed. Place hams' on the bottom of the container,
shoulders next, bacon sides and smaller cuts on top. Pour on the brine,
and be sure it covers the meat thoroughly. In five days pour off the
brine and change the meat, placing the top meat on the bottom and
the bottom meat on top, then pour back the brine. Repeat this opera-
tion again on the tenth, and eighteenth days. If the pickle becomes
ropy, take out all the meat and wash it off thoroughly, also the con-
tainer. Boil the ropy pickle; or, better, make new pickle. When
each piece of meat has received the proper cure, take it out of the
pickle and wash in lukewarm water, string and hang in the smoke-
house.
"Dry Curing—Make up a mixture, as follows", for each 100 pounds
of meat:
7 pounds salt
2^
pounds, sugar
2 ounces saltpeter.
"Mix all ingredients thoroughly, then rub one-third of the quantity
of this mixture over the meat and pack it away in a box or on a
table. The third day break bulk and rub on half of the remaining
mixture over the meat and again pack the meat. Break bulk the
seventh day and rub the remainder of the mixture over the meat and
pack the meat to cure. Allow one day and a half cure for each
pound the pieces of meat average. After the meat has cured, wash
each piece with lukewarm water and hang in the smokehouse.
"Fatbacks—Cut the fat backs into suitable pieces for curing and
pack them in a container. Make up a mixture, as follows
1
, for each 100
pounds of meat:
10 pounds salt
2 ounces saltpeter
4 gallons water.
240 INDUSTRIAL FERMENTATIONS
"Pour this mixture over the meat, adding enough more water if
necessary to cover it completely. , ., .
"Smoking helps to preserve the meat. If properly done it gives a
desirable flavor. . , , ,. , -
mo
"The smokehouse can be made any suse and of the kuid of ma-
terial suitable to the demands of the owner. If a very small quantity
of meat is to be smoked once a year, a barrel or a box will answer
On the other hand, if a considerable quantity of meat is smoked
and the house is to be permanent, it should be built of bnck, concrete,
After Oooh
to.
UA
Bjr.
Dommmt
808
FIG.
38
—An Indian saknon-drying rack, Bering Sea, Alaska.
or stone, to be
fireproof.
A small outdwelling can be used, if care
is taken to confine the fire to the center of the room in an iron kettle.
The safest method is to construct a fire pit outside of the house and
pipe the smoke into the house. The pipe running from the pit to the
house should be buried to prevent crushing.
"A smokehouse 6 by 8 ft. 10 ft. high, will give best results for
general farm use. Ventilation should be provided to carry off the
warm air and prevent overheating of the meat. Small openings under
the eaves or a chimney in the roof will control ventilation. If arrange-
ments can not be made to have a fire pit outside the house it can be
built on the floor and a metal sheet constructed to shield the meat. If
the meat can be hung 6 to 7 feet above the fire, this shield will not