The perfect shade of red starts with a bug. Make that 3,375 of them.

That's how many cochineal insects it takes to make one ounce of the red dye used to color clothing and food.

The Louisiana Art & Science Museum is celebrating "The Red that Colored the World" in its new exhibit.

Examples of it will fill the museum's main galleries through Jan. 14 in celebration of Baton Rouge's bicentennial. The traveling show was organized by the Museum of International Folk Art in Santa Fe, New Mexico.

"This show speaks to our fascination with the color red," curator Elizabeth Weinstein says. "We associate it with passion, beauty and strong emotions, like love and anger."

Red became a hot commodity when it was discovered in Mexico that a deep dye could be created by crushing the tiny bugs that congregate on prickly pear cacti.

"There isn't any information about how this was discovered, but in most cases, things like this are discovered by accident," Weinstein says. "We know the Aztecs and the Incas were using it."

The dye played a big role in Spain's economy after it colonized Mexico, then known as New Spain.

"It was Spain's second-largest import, falling only behind silver, which was the first," Weinstein says. "They traded it throughout the world."

And even the world's biggest names wanted a piece of it. Napoleon used cochineal to dye the fabric of his chamber chairs. Francisco Goya used it in his paintings, and history indicates that cochineal was the basis for Queen Elizabeth I's trademark red lips in the 1500s.

Yet, cochineal's history isn't all connected to historical figures. The textiles, paintings, sculptures and clothing in the Louisiana Art & Science Museum tell the story of how everyday people throughout the world utilized the dye.

Ramon Jose Lopez used the dye in to portray the harvesting of the insects in his "Cosecha de Cochineal." 

In it, three men from different eras gather around a cactus filled with red dots representing the insects that are native to Mexico and parts of South America. When the small bugs gather in the thousands to feed on the prickly pear cacti, harvesters brush them off into containers.

The bugs are then dried and crushed to produce a red carminic acid, which is mixed with a mordant to make the dye. It takes 70,000 of the bugs to make a pound of red dye.

"But you don't need much," Weinstein says. "We have an interactive exhibit that accompanies the main exhibit, and it include's a child's sweater. The sweater is made of wool, and it took only an ounce to dye the sweater."

The show's artifacts also include examples that span time and hues of the shade, from blankets made in the 1700s to an elegant, modern-day evening gown.

"It was discovered that when you can add different ingredients to change the shade," Weinstein says, and the exhibit highlights objects from the lightest pink to the brightest orange to the darkest purple.

Cochineal's popularity plummeted in the 1800s when Victorian society associated the color red with sin. The era also marked the beginning of synthetic dyes, which were more accessible.    

Cochineal found new audiences in the 1960s with a renewed interest in natural products but then came the 1970s when the FDA banned the use of Red Dye No. 2 because of its possible carcinogenic effects.

Red M & M's disappeared for a decade because of the ruling, but other food and cosmetic companies opted for the bug-based red, which has increased the demand.

"There are other names for cochineal — carmine, crimson lake, natural red No. 4," Weinstein says. "But it's all this same, beautiful red that was desired throughout the world."

And it's on display in a city where red has been prominent for 200 years.


"The Red that Colored the World"

A traveling exhibit organized by the Museum of International Folk Art in Santa Fe, New Mexico

WHEN: 10 a.m. to 3 p.m. Tuesdays through Fridays, 10 a.m. to 5 p.m. Saturdays, 1 p.m. to 4 p.m. Sundays. Through Jan. 14.

WHERE: Louisiana Art & Science Museum, 100 S. River Road.

ADMISSION: $9; $7.50, ages 3-12 and ages 65 and older. $8 for college students' first visit and a year's membership. 

INFORMATION: (225) 344-5272 or lasm.org.

Follow Robin Miller on Twitter, @rmillerbr.