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Page:Popular Science Monthly Volume 35.djvu/113

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101
EGGS IN CHEMISTRY AND COMMERCE.

end always uppermost, unless they have been shaken considerably, when they will stand either end up.

How to keep eggs is a problem that has attracted the attention of inquirers from the earliest times. Twenty or more processes are generally known, all of which give unsatisfactory and incomplete results—a circumstance scarcely to be wondered at when the composition of an egg and the various changes to which it is subjected by exposure to atmospheric influence are taken into consideration. The egg-shell is furnished with numerous pores, through which the water evaporates, the loss of aqueous contents thus sustained being scarcely perceptible in the first week, more marked in the second, and of considerable interest in the third. The surrounding atmospheric air takes the place of the water that has evaporated, and oxygenates the contents of the shell, which then commence to ferment and are speedily spoiled. To hinder this evaporation, and so aid the preservation of eggs, they are often steeped for twelve hours in lime-water, by which means molecules of lime are deposited on the shell, and so obstruct the pores to some extent.

To the solution of the problem of how to prevent the air from penetrating the shell of the egg, the experiments of such eminent savants as Musschenbroek, Réaumur, and Nollet have greatly contributed. They all agree that the most practicable method is to envelop the new-laid egg in a light coating of some impermeable substance, such as wax, tallow, oil, or a mixture of wax and olive-oil, or of olive-oil and tallow. Réaumur suggested an alcoholic solution of resin, or a thick solution of gelatin. Nollet experimented successfully with India-rubber, collodion, and various kinds of varnish. At the Dairy Products Show at the Agricultural Hall in 1884, three prizes were awarded for eggs preserved in the following manner:

1. Eggs which had been dipped twice in a solution of gum arable and then dried, enveloped in paper, and kept in bran.

2. Eggs which had been rubbed with lard and then kept in dry salt.

3. Eggs coated with a composition of mutton and beef suet, and then wiped with a dry cloth.

With a view to utilizing in a more portable and consequently cheaper form the large supply of eggs obtainable in Austria, Messrs. Effner & Co. started a factory at Passau, in Bavaria, for condensing them. The eggs are carefully selected and dried, then reduced to a fine meal, and packed in tins ready for use. Although it is scarcely probable that the condensed egg can ever replace new-laid eggs for breakfast, it is asserted that a good omelet, as also the finest pastry, may be prepared from the product.