Page:Foods and their adulteration; origin, manufacture, and composition of food products; description of common adulterations, food standards, and national food laws and regulations (IA foodstheiradulte02wile).pdf/179

 described. The white sturgeon or Oregon sturgeon is found on the Pacific coast from Monterey north to Alaska. It ascends the large rivers during the spring, notably the Sacramento, Columbia, and Fraser rivers. Some of them are very large and their value for food and commercial purposes has only been lately recognized. They are principally valuable, however, for their eggs or roe, since it is from the eggs of sturgeon that caviar is made. The roe in the fresh state is worth from 25 to 30 cents a pound. The fresh fish are frozen and shipped to Eastern markets.

The common sturgeon (Acipenser sturio) frequents the east and north Atlantic coast and ascends the rivers in the spring, especially the Delaware. The quantity of sturgeon taken, however, has constantly decreased for several years. The principal part of the caviar made in the United States is procured from the common sturgeon and the Lake sturgeon, which is found in the Great Lakes, the upper Mississippi Valley, and the Lake of the Woods.

Preparation of Caviar.—After the eggs have been removed from the fish, they are placed in large masses upon a stand, the top of which is formed of a small-meshed screen. On the under side is placed a zinc-lined trough, about 18 inches deep, 2 feet wide and 4 feet long. The operator gently rubs the mass of eggs back and forth over the screen, whose mesh is just large enough to let the eggs drop through as they are separated from the enveloping membrane. They thus fall into the trough from which they are drawn off into tubs through a sliding door in one end of the trough. After all the roe has been separated, the tub is removed and a certain proportion of the best Luneberg salt is added and mixed with the eggs by careful stirring with the hands. This is the most delicate part of the whole process, and the best results can be obtained by that proficiency which comes from long experience. After adding the salt, the eggs at first become dry, but in 10 or 15 minutes the salt has drawn from the eggs their watery constituents and a copious brine is formed, which is poured off when the tub becomes too full. The salted eggs are then poured into fine-meshed sieves which hold about 10 pounds each, where they are allowed to drain for 8 to 20 hours. The eggs have now become the caviar of commerce, which is put in casks or cans of various sizes.

Composition of the Flesh of Sturgeon.—

Water,     78.71 percent Protein,   17.96    "      85.19 percent Fat,         1.90    "       8.90    " Ash,         1.43    "       6.72    "

Composition of Caviar.—

Water,        66.05 percent Protein,      14.37    " Fat,            8.97    " Ash,           7.26    " Undetermined,   3.35    "

Of the ash, 6.16 parts of the 7.26 present are common salt.