The nature of the bitters used in beer has long been the target towards which public suspicion is directed, and nearly every substance known possessing a bitter taste has been enumerated among the adulterations of beer, from poisonous alkaloids, such as strychnin and picrotoxin, to harmless or quasi-harmless bitter roots and woods, such as quassia, gentian, etc. Complete and exhaustive schemes of analysis have been compiled, such as Dragendorff's, Ender's, etc, for the detection and isolation of such foreign bitters. Either these methods of investigation are faulty or difficult of manipulation, or the use of foreign bitters is very much less prevalent than is generally supposed, for the cases where such bitters have been detected and isolated are very scarce in chemical literature. In fact, Eisner, a German authority on food adulterations, goes so far as to say that there has never been a case where the existence of a foreign bitter in a malt liquor has been proven with certainty. This is going too far, of course, for picrotoxin and picric acid have undoubtedly been found in beers, and probably more cases of such adulteration would occasionally have been discovered were it not for the difficulty of the analysis and the small quantity of matter required for imparting a bitter taste. But there is probably much less of this hop substitution than the space given it in works on the subject would indicate. Hops not only give the bitterness to beer but also impart to it its peculiar aroma, and enhance its keeping qualities, and unless it were at a time when they were very dear it would hardly pay the brewer to sacrifice the good flavor and keeping qualities of his beer in order to save a few cents a pound in his bitters.

It is stated by authorities on the subject that the bitter matter of hops is precipitated by acetate of lead, while with all hop substitutes the filtrate from the lead precipitate retains its bitter taste. The excess of lead should be precipitated by sulphureted hydrogen before the filtrate is tasted for bitterness. I examined qualitatively by this test all the samples analyzed and found them all free from foreign bitters according to it, with one exception, No. 4811, which contained a bitter other than hops, though not in sufficient quantity to admit of its separation and identification. All the samples except Nos. 4801, 4811, and 4815 gave a plainly perceptible odor of hops in the distillate.1