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/198

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COMPARATIVE PERCENTAGE COMPOSITION OF OYSTERS BEFORE AND AFTER "FLOATING."—(Continued.)

———————————————————————-+——————————————-+——————————————
                                               | James River Oysters | Potomac River Oysters
                                               | Transplanted To | Transplanted To
                                               | New Haven. | New Haven.
———————————————————————-+———————+———————+———————+——————-
Constituents of Oysters. | As taken | As taken | As taken | As taken
                                               | from beds. | from floats. | from beds. | from floats.
                                               +———————+———————+———————+——————-
                                               | No. 82. | No. 83. | No. 85. | No. 84.
———————————————————————-+———————+———————+———————+——————-
In whole specimen: | Percent. | Percent. | Percent. | Percent. | | |
Shell contents: | | | |
Nitrogen | 0.18 | 0.18 | 0.16 | 0.17
Protein (nitrogen × 6.25) | 1.12 | 1.12 | 1.00 | 1.06
Fat (ether extract) | 0.25 | 0.22 | 0.20 | 0.20
Ash | 0.35 | 0.26 | 0.37 | 0.24
Carbohydrates, etc. (by difference) | 0.66 | 0.64 | 0.67 | 0.61
                                               +==============+==============+==============+=============
Total water-free substance | 2.38 | 2.24 | 2.24 | 2.11
Water | 12.62 | 14.93 | 13.89 | 14.55
                                               +———————+———————+———————+——————-
Total shell-contents | 15.00 | 17.17 | 16.13 | 16.66
—————————————————————————————————————————————————————

Result of Treatment.—As shown by the data the first result is one which would naturally be expected, namely, that the total weight of the oyster thus inflated with water is increased relatively to the total weight of the shell since no change takes place in the weight of the shell during floating. The gain of weight in the oyster is due to the absorption of the water, although there is a loss of mineral salt. The average gain of the oyster was, in round numbers, 10 percent. The danger of infecting oysters thus treated with any germs, which may be present in the water or ice used, should also be taken into consideration.

In respect of the composition of the oyster itself when subjected to floating the chief change is in the increase of the water content. As has already been said the process of floating is fatal to the flavor and palatability of the product.

Adulteration.—The chief adulterations of oysters are the "floating" above described and the treatment of the "shucked" oysters with formaldehyde, boron compounds, and other preservatives to keep them from spoiling. These processes are thoroughly reprehensible and are rapidly disappearing. The consumer who lives near the source of supply should never eat any but freshly shelled oysters and those at a distance confine themselves to the properly prepared and shipped article. The chief delight of the epicure is the freshness, and not the quantity of nourishment of this justly prized bivalve.

Average Composition of Oysters:[1]

Water, 60.08 percent
Solids, 39.92 "
Nitrogen, 1.56 "
Phosphoric acid, .42 "
Sulfur, .19 "
Fat, 9.48 "
Ash, 1.77 "
Protein, 9.73 "

  1. Average of samples used at Hygienic Table, Bureau of Chemistry.