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/196

 shown in the table given below, in 10 pounds of the meat there is over 80 percent of water it is seen that the actual nourishment contained in 100 pounds of oysters is reduced to a little over 1 pound. There is a general opinion that oysters are a very nutritious food and this is true in so far as the nitrogenous element of food, that is, the protein, is concerned, and in proportion to the quantity present. As a nourishing food the oyster cannot be considered as worthy of any very great esteem. It must be confessed that it will continue to be used as it has been in the past, that is, practically, as a condimental food substance and not to satisfy hunger nor provide the heat and energy of the human activities.

Process of Floating.—Reference has already been made to the practice of soaking oysters in fresh water for the purpose of making them more plump and increasing their weight. This, in the language of the fisherman, is called "floating," "drinking," or "laying out." By this process the body of the oyster affects a plumpness and largeness which materially increases its selling qualities, as it increases its weight and size and, therefore, the profits of the dealer. The principle of this process depends upon the fact that when a soft substance like an oyster, containing a mineral salt in its composition, is brought in contact with water, a process of diffusion takes place which is known, in chemical physics, as osmosis, whereby water passes through the cell walls and enters the cells of the oyster and the mineral substance thereof is forced out into the external water. Larger volumes of water pass into the cells than accompany the particles of mineral matter to the outside of the cells and the result is a swelling of the oysters and consequent increase in the size and weight by the addition of pure water, but at the expense of the natural salt, mostly chlorid of sodium or common salt, which the oyster contains.

The U. S. Bureau of Fisheries has been experimenting to show the change which takes place with the following results:—

STATISTICS OF WEIGHTS, ETC., OF SPECIMENS OF OYSTERS. -                |                          |             -++++                 |                    |                    |                    |    |     From beds. |   From floats. |    From beds. |   From floats. ++++                |  Lab. No. 82; 31  |  Lab. No. 83; 34  |  Lab. No. 85; 35  |  Lab. No. 84; 41 |    oysters. |    oysters. |    oysters. |    oysters. -++-++-++-++- Shell contents: |  Grms. | ''Lbs. Oz. | Grms. | Lbs. Oz. | Grms. | Lbs. Oz. | Grms. | Lbs. Oz.'' Flesh (body)    |  312.5 |      11.0 |  412.5 |      14.5 |  302.5 |      10.7 |  415.5 |      14.7 Liquids (liquor) | 181.5 |       6.4 |  208.0 |       7.3 |  282.0 |      10.0 |  264.3 |       9.3 ++-++-++-++- Total           |  494.0 |  1    1.4 |  620.5 |  1    5.8 |  584.5 |  1    4.7 |  679.8 |  1    8.0 +========+===========+========+===========+========+===========+========+=========== Refuse:         |        |           |        |           |        |           |        | Shells          | 2778.0 |  6    2.0 | 2976.0 |  6    9.1 | 3017.0 |  6   10.4 | 3386.0 |  7    7.4 Loss         |   21.0 |       0.8 |   17.5 |       0.6 |   22.5 |       0.8 |   15.2 |       0.5 ++-++-++-++- Total           | 2799.0 |  6    2.8 | 2993.5 |  6    9.7 | 3039.5 |  6   11.2 | 3401.2 |  7    7.9 +========+===========+========+===========+========+===========+========+=========== Total weight of |        |           |        |           |        |           |        | specimen        | 3293.0 |  7    4.2 | 3614.0 |  7   15.5 | 3624.0 |  7   15.9 | 4081.0 |  8   15.9 -++-++-++-++-