Drop is the Dutch word for licorice candy. It is made from the extract of the root of the licorice plant (Glycyrrhiza glabra; in Dutch zoethout, "sweet wood"), bound with sugar, starch or gum arabic and often flavoured with salt, ammonium chloride, honey, laurel, anise or mint. Its history in the Netherlands runs from medicine to mass-produced sweet.
Licorice as medicine
Licorice root has been used medicinally for thousands of years around the Mediterranean and in Asia, mainly for coughs and sore throats and for stomach complaints. In early modern Europe the thickened juice of the root was sold by apothecaries. In England, licorice grown around Pontefract in Yorkshire was made into small medicinal lozenges, the ancestors of Pontefract cakes. In the Low Countries the extract was imported and sold in a similar way.
Why it is called "drop"
The usual explanation, given for example by Dutch Wikipedia, is that the name comes from the "solidified drops" (gestolde druppels) of licorice extract sold as medicine; the word is recorded in this sense in the early seventeenth century. Dutch drop therefore means both "drop" (of liquid) and "licorice". English speakers in the Netherlands often say "Dutch drop" or "Dutch licorice" to make the meaning clear.
From pharmacy to factory
In the nineteenth century licorice moved from the pharmacy counter to the sweet shop. Steam-powered confectionery factories made drop alongside peppermint and jujubes, and several of today's brands date from this period: Klene began in Rotterdam in 1876 and Venco in Amsterdam in 1878. In the twentieth century production consolidated in larger plants, such as Red Band's factory in Roosendaal (1928), which now also makes Venco. Even so, the boundary with medicine never fully closed: Dutch drugstores still sell keelpastilles (throat pastilles) containing licorice, and old-fashioned laurierdrop and dropwater were long treated as remedies for coughs.
Salt and salmiak
What most clearly separates Dutch (and Nordic) licorice from the sweet licorice of Britain, Italy or the United States is salt. Zoute drop is flavoured with ammonium chloride, called salmiak, sometimes together with ordinary salt; the strongest versions are sold as dubbelzout. Ammonium chloride itself was long sold by pharmacists as a cough remedy, which is one plausible route by which it entered licorice, although exact dates for the first salty drop are hard to pin down. The salty taste is shared with Finland, Sweden, Norway, Denmark, Iceland and northern Germany, and is largely unknown elsewhere. See salmiak and the chemistry of licorice.
How much drop the Dutch eat
The Netherlands is usually described as one of the world's largest consumers of licorice per head. Dutch Wikipedia cites figures from around 2008 of roughly 32 million kilograms a year, about 2 kg per person, with around 80% of the population eating drop at least occasionally. Finland is often named as the other leading licorice country. Treat any per-capita ranking with caution: published figures are old, differ by source and rarely use the same definition of "licorice".
Where Dutch drop is made today
Most branded Dutch drop is still made in the Netherlands, by a small number of large companies (see Dutch candy brands) and many smaller makers. The licorice root and extract, however, are imported, since the plant is grown commercially mainly in countries such as Turkey, Iran, Uzbekistan, Afghanistan, Italy and Spain. For the manufacturing process, see how drop is made.