Cochineal is produced by the female cochineal bug. Dactylopius coccus is the species most often encountered. These insects are parasites on prickly pears (Opuntia). The red dye is carminic acid, which is thought to be produced by the insect to deter predator ants. The female insect is about 0.1 to 0.2 inches long and is gray but it secretes a mass of cottonlike material that surrounds it, not unlike a mealybug. The sedentary female insects feed on the juices of many species of prickly pears. The male insects can fly but do not feed and only live long enough to mate.

Cochineal dye had been used in North and South America since ancient times. The Paracas people of Peru were using it 2400 to 1800 years ago. The Aztecs and Maya also used it. Aztec emperors wore red robes dyed with cochineal. Moctezuma commanded that eleven cities he conquered pay an annual tribute of forty bags each of cochineal. The dye was said to be worth more than its weight in gold. Insects were farmed on large plantations of Opuntia cochenillifera.

Cochineal insects, female on the left and male on the right

The Spanish were also impressed with cochineal. The dye probably reached Europe by the middle of the sixteenth century and was soon in demand for royal and clerical capes and robes. The Spanish had a monopoly on the dye and regarding Mexican exports, the value of the dye was second only to silver. The source was a closely-guarded secret for years. Then in 1704, Antoni van Leeuwenhoek, using his new invention the microscope, discovered insect parts in the dye. However, Mexico still maintained a monopoly on the dye until after the Mexican War of Independence of 1810-1821.

It takes approximately 64,000 insects to make one pound of dye powder. The dye works better on animal fibers than on plant fibers and some historic wool jackets were dyed with cochineal. The British Redcoats in the American Revolution wore coats dyed with cochineal, as did the North-West Mounted Police.

Synthetic dyes nearly wiped out the cochineal industry for a time. In the twentieth century, the dye became a curiosity rather than a valuable commodity. Then interest arose in using safer and noncarcinogenic dyes in foods and cosmetics and the industry was saved. Currently, cochineal is raised in Mexico, Peru, Chile, the Canary Islands, and Eritrea. Peru is the largest producer. Opuntia ficus-indica is the host plant most commonly used. The dye is used to color juices, ice cream, yogurt, and candy. It is also used in cosmetics like eye shadow, lipstick, and rouge.

In general, the dye is safe to use for food and cosmetics though like most anything else, a small percentage of people are allergic to it. The Hyperactive Children's Support Group recommends that the dye be eliminated from the diet of hyperactive children. Products containing cochineal may be unacceptable to vegetarian or vegan consumers. Many Muslims and Jews avoid the product. Food products containing cochineal may be labeled as containing 'cochineal extract' or 'carmine'.

Cochineal insects can become so numerous that they kill their host. Prickly pears have been imported all over the world for food and horticulture. In some countries, the cactus ran rampant and invaded thousands of acres of land. Various predator insects have been imported to control the cactus and a species of cochineal insect has resulted in effective control of prickly pears in South Africa and Hawaii.

Cochineal is a substance with an interesting origin, an interesting history, and an interesting present. From the robes of emperors to a tube of lipstick, the color red depends on a humble insect and the prickly pear cactus.

Illustrations are courtesy of Wikimedia Commons. Thumbnail photo is by Frank Vincentz.