Cochineal - It's to Dye for
Colonies of cochineal on your cactus
If you’re either squeamish or vegetarian, you may want to stop reading now. Why? Because not only are there tiny scale insects called cochineal hunkered down on the prickly pear cactus in your front yard, someone in Peru is collecting these same insects with the intent of adding them to your morning yoghurt.
It sounds bizarre, like scorpions on a stick (those are commonly for sale, believe it or not), but cochineal scale (Dactylopius sp.) has been used as a deep, rich, red dye for well over a thousand years. It is a native insect found throughout the Sonoran Desert and central and South America, as are the many species of prickly pear in the genus Opuntia that it relishes as its host plant.
Rub a pinch of this white fluff between your fingers and you will feel the gritty crunch of a dozen female insects who have just sacrificed themselves for your curiosity.
If you live in the desert southwest of the U.S., you’ve undoubtedly seen a prickly pear pad covered in overlapping blotches of what look like thin layers of fluffy-white buttercream frosting with a little red velvet cake showing through. Rub a pinch of this fluff between your fingers and you will feel the gritty crunch of a dozen female insects who have just sacrificed themselves for your curiosity. The females build this waxy, white coating to protect themselves, but when discovered and crushed, their once-plump bodies exude a juicy, blood-like pigment that will stain your fingertips for hours in the same way that fibers like cotton have been dyed for centuries.
With a garden hose, cochineal on a prickly pear is easily controlled with a sharply focused blast of water. But in places like La Joya, Peru and the Mala-Guatiza region of the Canary Islands, that wouldn’t be good business. There, these insects are not just encouraged, but farmed.
Female cochineal scale insects lay eggs that hatch into six-legged nymphs called “crawlers.” The crawlers create a wispy filamentous wax which can catch the wind and transport them to other pads and plants. They wander around until they find a place to their liking on a prickly pear pad, then sink their proboscis into it and spend the rest of their lives in this one spot, feeding on the sap. They go through several molts, lose their legs, and secrete a protective waxy coating (the frosting), eventually reaching maturity at about ¼ inch long.
Commercially, it’s at this stage when the individuals are harvested for their pigment. It takes about 70,000 female cochineal insects to make one pound of dye. Peru is the world’s largest supplier, sometimes inoculating a density of 25,000 prickly pears plants (predominantly Opuntia ficus-indica) per acre with cochineal breeding stock.
In Oaxaca, Mexico (see photo, above), tubes filled with several grams of mature cochineals are affixed to the Opuntia pads. The bugs oviposit (lay eggs) inside the tubes, then the first instar (first generation) of crawlers move out onto the surface of the pads and develop in the same way as cochineals do in the wild. This cultivation method is similar to that used in Chile, Peru, and the Canary Islands. In Chile and Peru, they are harvested with metal spoons or brushes, cleaned, sorted, and then killed by immersing them in hexane. They are then dried and packaged for sale.
Cochineal farming in Peru only comprises 15% of Peru’s total output; the other 85% is harvested from the wild as a cottage industry.
Eventually, dyes die
When the Spanish empire reached Mexico in 1520, they found the Aztecs wearing textiles dyed with many vibrant, color-fast hues of red derived from cochineal. Up to that point, the weaker “reds” of Europe had come from the roots of madder (Rubia tinctorum), and kermes, another dye derived from the body of an insect. When cochineal was brought to Europe, it was an immediate hit, lasting over 300 years as the predominant red coloration for fabrics, including the robes of kings and the uniforms of British redcoats.
Cochineal began to lose ground to coal-tar based dyes in the 1850s, and then was lost to all but fiber artisans in the early 1920s with the wide availability of aniline dyes. But its popularity picked up again as an edible, natural colorant for food and cosmetics.
Carminic acid is the principal red pigment in cochineal and its purified form is called carmine. Originally, in the U.S., cochineal was listed on food labels as “natural coloring,” but since 2009, the FDA has required that it be specifically identified as carmine or cochineal extract, in part, because of the occasional allergic reactions that it can generate.
- #1: Cochineal was second only to silver as an export product of Spain during the early years of its viceroyalty in Mexico and central and South America. It was used as money by the indigenous peoples governed by Spain who were forced to pay for goods with dried cochineal.
- #2: In order to protect their monopoly on cochineal, the Spanish kept the knowledge of its cultivation secret until the seventeenth century, even claiming that the dye came from a seed, not an insect.
- #3: Certain species of Opuntia became serious weeds in other countries, particularly Australia—up and until today—because of the desire to cultivate cochineal as a dye for British military uniforms and other uses. Ironically, a species of cochineal has proven to be an effective biological control for one species of Opuntia in Australia.
Yep, you might be eating it
To satisfy my own curiosity, I spent two-hours in my local supermarket reading the ingredients for every conceivable food item with a reddish hue (by the second hour, security was shadowing me). I found only four with a specific reference to cochineal, only a fraction of what I was expecting. They are:
- Yoplait Original Strawberry yoghurt
- Good and Plenty candy
- Nesquik Strawberry mix
- Dole Mixed Fruit in Black Cherry Gel
In 2012, after customer pushback, the CEO of Starbucks announced that the company was phasing out cochineal extract from its Raspberry Swirl Cake and five other cochineal-laced products. This switchover may have set the stage for a larger food industry flight from the wide use of cochineal, which would explain why I found so few products listing it. At last check, Starbucks is using tomato-based lycopene rather than cochineal to color two of its strawberry drinks.
Perhaps cochineal’s widest current use is in cosmetics, but there is pushback there, too. Several blogs and websites list “cochineal-free” cosmetic products, implying that cochineal is most likely present unless proven otherwise.
No matter if you wear it, eat it, or paint it on your lips, cochineal is as natural as a rattlesnake in the moonlight. Whether you decide to use it depends on your personal ethics, your tolerance for the “ick” factor, and ultimately, how much it bugs you.