For the methods of mixing the ingredients, see "Amandine," p. 195.
On account of the high price of the French oils, these preparations are expensive, but they are undoubtedly the most exquisite of cosmetiques.
SECTION X.
MILK, OR EMULSIONS.
In the perfumery trade, few articles meet with a more ready sale than that class of cosmetiques denominated milks. It has long been known that nearly all the seeds of plants which are called nuts, when decorticated and freed from their pellicle, on being reduced to a pulpy mass, and rubbed with about four times their weight of water, produce fluid which has every analogy to cow's milk. The milky appearance of these emulsions is due to the minute mechanical division of the oil derived from the nuts being diffused through the water. All these emulsions possess great chemical interest on account of their rapid decomposition, and the products emanating from their fermentation, especially that made with sweet almonds and pistachios (Pistachia vera).
In the manufacture of various milks for sale, careful manipulation is of the utmost importance, otherwise these emulsions "will not keep;" hence more loss than profit.
"Transformation takes place in the elements of vegetable caseine (existing in seeds) from the very moment that sweet almonds are converted into almond-milk."—Liebig. This accounts for the difficulty many persons find in making milk of almonds that does not spontaneously divide, a day or so after its manufacture.