COMMERCIAL CANNING OF FOODS. 73 
pox, which accommodates 3 cars. The steamer is a rectangular iron box, just 
large enough to admit the cars, and is 25 feet in length. There are a few variations 
from these sizes, but these are standard. The doors are closed at both ends; steam is 
turned on until a pressure of 10 pounds is reached, and this is maintained for 5 minutes. 
The doors are then opened and the oysters allowed to cool quickly in the air. It is 
important that the oysters be steamed well so that there will be no shrinkage in the 
ean, but not long enough to cause them to become crummy. Both the time and the 
temperature at which the steaming is done seem to have been fixed by experience, 
as none of the superintendents seemed to know what the effect would be if a lower 
' temperature and longer time or higher temperature and shorter time were given. 
The car of steamed oysters is pushed into the shucking shed, the shuckers standing 
_ around the car and working until it is emptied. The usual number of shuckers is 
from five to eight, and they are generally women and children. 
The steamed oyster has the shell partly opened, the meat being easily removed by 
_ means of a short, heavy-bladed knife. The oysters are deposited in pans which are 
' hooked to the oyster car. The shucker receives 5 cents for 34 pounds of selects or 3 
pounds of standards. The oysters are weighed as received from the shuckers, washed, 
| : and placed in cans by weight according to the grade and order. The cans are filled 
4 with a weak hot brine (2 pounds of salt to 10 gallons of water) frequently by passing 
_ the cans through a dip box. This method was used at one time in other lines of can- 
NM ning, but has been superseded by more sanitary methods, and should be in this case. 
The cans are capped in the usual manner, either by hand or machine, and are then 
processed in the retort at 240° F., the No. 1 cans for 12 minutes and the No. 2 for 15 
minutes. The different packers vary the time a few minutes, but practically all use 
_ the same temperature. 
The oysters are cooled as soon as sterilized, and when dry are ready to pack. The 
oyster is easily sterilized, it is not hard on the can, and there is little loss from spoilage. 
The term ‘“‘cove” is applied to any canned oyster. It originally meant only the 
oysters obtained on the western shores of Chesapeake Bay and was distinctive of 
“4 quality. Gradually any oyster became a cove oyster, and now the term refers to 
canned oysters irrespective of where they are obtained. 
SALMON. 
Salmon canning on the Pacific coast is one of the large canning industries, and is of 
so much importance that Government aid is extended in maintaining fish hatcheries 
in order to keep up the supply. The first salmon canning was done on the Sacramento 
River in 1864, later on the Columbia River in 1866, in British Columbia in 1874, and 
in Alaska in 1882. The value of the salmon pack on the Pacific coast is more than 
$10,000,009 annually. ; 
There are four species of salmon which have large commercial importance—Onco- 
rhynchus tschawytscha, the chinook, quinnat, red spring, or King Alaska; O. nerka, the 
sockeye, blueback, or redfish; O. kiswtch, cohoe, silver, or silver sides; and O. gor- 
buscha, humpbacks or pink Alaska. Preference is given to the bright pink color by the 
consumer, but for real quality the paler cohoe excels some of the others, the flesh being 
less dry and containing more oil and a beiter flavor. 
The salmon are caught in the rivers as soon as practicable after they leave the sea 
on the way to the spawning grounds. They are caught by nets, selnes, traps, and fish 
wheeis. The catching of the fish is done on an elaborate scale, an idea of which may 
be gained from a brief description of a trap. This consists of a steel-wire netting, 
starting at the shore and carried out into the stream at an upward angle for a distance 
of about.2,500 feet. This netting is supported by piles placed about 15 feet apart. At 
the outer end is a large square compartment known as the pot. This is usually about 
40 by 40 feet and in water as deep as 65 feet. This pot contains a dip net equal to its 
area. Just previous to reaching the pot the trap is made to zigzag or assume a heart 
shape, so that the fish in trying to pass up the stream will be directed into the pot. 
