Important: Safety Warning
This page describes trade processes that use dangerously toxic materials such as cyanide solutions, mercury amalgams, or strong acids. These processes require training, equipment, and precautions far beyond what the text describes.
This page describes additives or treatments for food or drink that are now known to be toxic and are prohibited in food today.
This information has been left in for historical purposes but should not be acted upon.
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Beading for Proof Brandy
Beading for Proof Brandy.
The "bead" of brandy, or other liquors, is the small globules, or bubbles that remain on top when the liquid is agitated. The bead of a liquor is supposed to show its strength; for instance, if you agitate a quantity of spirit in a glass, and the bead remains on the top a few minutes, it is called proof spirit, but if, when the agitation is discontinued, the bubbles rapidly disappear, the spirit is supposed to be below proof. The bead heretofore generally used by dealers, is that made by mixing sweet oil and sulphuric acid in the following proportions: To every forty drops of sulphuric acid, add sixty dropa pure sweet oil. This quantity is generally sufficient to give a bead to ten gallons spirit; but sometimes the alcohol will contain substances, such as acids, alum, or alkalies, that may in a degree neutralize the efficiency of the mixture, and it will in that case require a greater quantity to give the proper "bead." This mixture does not improve by age, and should therefore only be prepared when wanted for use. In mixing, be careful and put the ingredients in a glass vessel. With the exception of that of almonds, olive oil being the most costly of the ordinary fixed oils of commerce, it is consequently the one most subject to adulteration. Nut, poppy, rape, and lard oil are those commonly most used for this purpose. The following test will show whether the oil is pure :- When pure olive oil is shaken in a phial only half filled, the bubbles rapidly disappear; but if the sample has been mixed with poppy or other oil, the bubbles continue longer before they burst. Any pure fixed oil will answer to make the above "bead." To ascertain if an oil is pure, mix with it an equal quantity of nitric acid : if the margin of this combination assumes a yellowish
This is not a drink so much as a fraud: a mixture meant to be stirred into spirit so that it looks stronger than it is. The materials and the intent both put it outside anything that can be attempted today.
- Sulphuric acid in a drinkSulphuric acid ("oil of vitriol") is a corrosive mineral acid, not a food ingredient. Forty drops per ten gallons is a small dose by volume, but the acid is being added to a liquid intended for human consumption and has no legal or safe use there. It also attacks skin, eyes and lungs in the undiluted form the recipe calls for handling.
- The acid-and-oil reaction itselfMixing concentrated sulphuric acid with a fixed oil produces sulphonated fatty acids and other breakdown compounds of uncertain composition; these are the surfactants that hold the bubbles. The reaction gives off heat. The text does not explain itself, but it does insist on a glass vessel and on making the mixture only when wanted, saying it 'does not improve by age.' None of it belongs in brandy.
- The nitric acid testThe unfinished final paragraph directs the reader to mix an equal volume of nitric acid with the oil. Concentrated nitric acid on organic matter reacts violently and gives off nitrogen dioxide, a brown gas that damages the lungs at low concentration. This is a fume-hood operation, not a countertop one.
- "Sweet oil"Nineteenth-century trade language for olive oil, which is why the passage drifts into a discussion of olive oil adulteration with poppy, rape, nut and lard oils. The book's shaken-phial test is genuine period practice and reasonably sound as far as it goes, but it distinguishes only viscosity and surface behaviour, not identity.
- Why the "bead" proves nothingWhy the 'bead' proves little -- Bubble persistence depends on surface tension and on any dissolved surfactants, so it can be manufactured independently of alcohol content. That is the loophole the recipe exploits, and the page itself shows the trade knew the test could be faked. Strength is properly measured by hydrometer, or today by density meter or gas chromatography.
- UnitsThe recipe uses forty drops of sulphuric acid to sixty drops of sweet oil per ten gallons of spirit. A 'drop' is an imprecise measure (roughly 0.05-0.06 mL, varying with the liquid), so forty drops is on the order of 2-3 mL. Whether the gallon is the US gallon of 3.79 L or the imperial gallon of 4.55 L is not stated, so ten gallons is somewhere around 38-45 L - a trade quantity, not a household one.
- If you want the real thingThere is no modernised version of this procedure. Judging or adjusting the strength of a spirit is done with a calibrated hydrometer and a current reference on proofing.
Books like this one appear to have been written with the retail trade of the mid-to-late nineteenth century in mind, when a dealer bought neutral spirit cheaply and turned it into "brandy," "whiskey" or "rum" with colouring, flavouring and various tricks of appearance. Buyers were said to judge strength by shaking a sample and watching the bead, and a whole small technology of faked beads grew up to defeat them, as the author says, "heretofore generally used by dealers." The passage is doubly revealing: it teaches the counterfeit in one breath and, in the next, frets that the olive oil the counterfeiter buys may itself be adulterated with poppy or lard oil. That mutual suspicion is the texture of the pre-regulation food trade, and it is the world the Pure Food and Drug Act of 1906 was written against.