This section is from the book "The Manufacture Of Liquors, Wines, And Cordials, Without The Aid Of Distillation", by Pierre Lacour. Also available from Amazon: Manufacture of Liquors, Wines, and Cordials, Without the Aid of Distillation.
There are two varieties of almonds, sweet and bitter.
Sweet Almonds, when blanched, which is easily done by immersing them in boiling water and rubbing them between the hands until the husk is removed.
are without smell, and have a sweet and pleasant taste.
Sweet almonds enter into the composition of various syrups, etc. They are also used for giving the appearance of age, and a nutty flavor and taste to all kinds of spirituous liquors. When this object is intended for fine brandies, etc, say for twenty gallons of the spirit, five ounces of sweet and one of bitter almonds are well worked to a paste with acetic ether in a mortar; the paste is then strained, being first diluted with a sufficiency of water; the strained product, being a milky emulsion, is added to the spirit, for wines, etc. Use in the same manner,
Bitter Almonds. - These are smaller than the preceding variety; they have the bitter taste of peach kernels, and though in their natural state inodorous, or nearly so, have when triturated with water the fragrance of the peach blossom. They contain the same ingredients as sweet almonds, and like them form a milky emulsion with water. Bitter almond meal is sometimes used in the quantities of three to five ounces to twenty gallons of spirit, for imparting a nutty taste. Much care should be used in selecting almonds that are not rancid, as they would be highly deleterious if added to a cordial or wine.
Oils of Sweet and Bitter Almonds. - The oil of sweet almonds is of a sweet bland taste, and may be substituted for all the uses of sweet oil. This oil is sometimes dissolved in ether or alcohol, and is used for the same purposes in liquors that the almond is for; from one to two ounces of the oil, to double that quantity of alcohol or ether.
Oil of Bitter Almonds has a yellowish color, a bitter acrid burning taste, and the peculiar odor of the kernels in a very high degree. The purity of this oil may be known by its ready solubility in sulphuric acid, with the production of a reddish brown color. Oil of bitter almonds is used as a flavoring ingredient in cordials, wines, and liquors, but more extensively in cordials. This odor is too well known and easily detected, and should be used in small quantities.
Is sometimes used in quantities of from one to five quarts to forty gallons of spirit; it is used in cases where catechu and alum would be objectionable on account of their easy detection in rum, brandy, etc. Ale gives a mild and pleasant bitter. Four pints of porter and one ounce of sulphuric acid added to forty gallons of spirit, will give a taste similar to the decoction of peaches. Where porter is not convenient, add an infusion of hops.
This root, as found in commerce, is usually much decayed internally; it is in pieces three or four inches long, from the thickness of a quill to that of the little finger, somewhat twisted, consisting of a dark red easily separated bark; it is reddish externally, and whitish near the centre, and composed of numerous distinct fibres, and internally of loose spongy texture. The fresh root has a faint odor and a bitter astringent taste, but when dried it is inodorous and insipid. It does not impart its color to water but to alcohol, and is used for coloring port wine and Stoughton's Bitters, etc. The red of alka-net is rendered deeper by the addition of an acid, and changed to blue by alkali.