Exactly as printed, 1863
Oil of Cognac.
The flavor belonging to genuine French brandy is due to a peculiar oil, known as oil of Cognac. This oil is obtained by distillation from the marc, or lees of wine, either dried or made up into cakes, or, in their wet state, mixed with about seven or eight times their weight of water. The brandy from any part of the world may be very closely imitated by distilling the oil from the marc of the wines produced in the particular district. Oil of Cognac is also prepared by dissolving the fusil oil of marc brandy in strong rectified spirit, and then adding a sufficient quantity of concentrated sulphuric acid to form a sulphate; alcohol and excess of acid is removed by washing the newly formed compound with water. To 100 lbs. of marc add ½ lb. sulphuric acid; the oil is generally formed towards the end of the distillation, and is found floating in blackish drops on the surface of the distillate. According to a distinguished French chemist, this oil is a compound of potatoe oil and enanthic ether. Cognac oil when pure, has a true vinous odor, and, like all essential oils, requires to be cut with strong alcohol. One ounce of the pure article is sufficient to flavor from 200 to 250 gallons. The manufacturer should be very careful when using this powerful oil: add a very little at a time, and remember more may be added if necessary.
Oil of Cognac is very generally adulterated with alco hol; indeed, it is extremely difficult to procure the really genuine article. As a test to ascertain whether it is pure, we offer the following simple method:-Take a half ounce phial, and fill it exactly half full with the oil, then fill up the remaining space with water, and shake it well; if the oil is adulterated with alcohol, the latter will leave the former and mix with the water, conse
The French Wine and Liquor Manufacturer, 1863. Public domain; transcription unaltered.