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Carmine ground pigment

Carmine

Carmine (/ˈkɑːrmən, ˈkɑːrmaɪn/) – also called cochineal (when it is extracted from the cochineal insect), cochineal extract, crimson lake, or carmine lake – is a pigment of a bright-red color obtained from the aluminium complex derived from carminic acid. Specific code names for the pigment include natural red 4, C.I. 75470, or E120. Carmine is also a general term for a particularly deep-red color.

Etymology[edit]

The English word "carmine" is derived from the French word carmin (12th century), from Medieval Latin carminium, and from Persian قرمز qirmiz ("crimson"), which itself derives from Middle Persian carmir ("red, crimson"). The Persian term carmir is likely cognate with Sanskrit krimiga ("insect-produced"), from krmi ("worm, insect"). The Persian word for "worm, insect" is kirm, and in Iran (Persia) the red colorant carmine was extracted from the bodies of dead female insects such as Kermes vermilio and cochineal. The form of the term may also have been influenced in Latin by minium ("red lead, cinnabar"), said to be of Iberian origin.

The word "carmine" has been used as a color name as early as 1799. It is a popular food color, used in yogurt, candy, gelatin, meat, and beverages including fruit juices.

History

Female Dactylopius coccus aka Cochineal bugs were already used for their red coloring power as far back as in the 700 BC. South American civilizations crushed the bugs present on cacti to extract the carmine they contain. Carmine pigment was extensively used by the Aztec civilization to dye textiles. It was imported later to Europe during the 16th century.

Red is a color often associated with power and social status. Through the centuries, red has been worn by tribal chiefs, kings and queens, and military officers.

In the 17th century, carmine dye made of cochineal and tin was used to color British military uniforms. This vibrant color was also present in aristocrats' closet.

The trade of cochineal was a major source of income for the Spanish Crown.

"In the 1610s, for instance, twenty-five pounds of cochineal cost sixty times more than an equivalent weight of sugar."

The Spanish Crown had a monopoly on the production of cochineal bugs until the 1820 when the French learned to cultivate them. Later, German and British scientists created a chemical red dye. The combination of these factors contributed to the end of the Spanish monopoly and considerably lowered the price of this red gold. As a consequence, carmine red became accessible to a wider audience.

In general, the history of the trade of cochineal remains linked to slavery and triangular trade.

Production

The pigment is produced from carminic acid, which is extracted from some scale insects such as the cochineal scale (Prima), and certain Porphyrophora species (Armenian cochineal and Polish cochineal). Cochineal is now farmed.

Carmine is a colorant used in the manufacture of artificial flowers, paints, crimson ink, rouge, food coloring, cosmetics, and some medications.

Synthetic carminic acid is complex to produce. Therefore, natural cochineal carmine is predominant on the market. However, its instability makes its use difficult in dye and painting, but a still a great ingredient for cosmetics.

Preparation

To prepare carmine, the powdered scale insect bodies are boiled in an ammonia or sodium carbonate solution. After separating the insoluble matter, the extract is treated with alum to precipitate the red solid. This precipitate is called "carmine lake" or "crimson lake". Purity of color is ensured by the absence of iron. Stannous chloride, citric acid, borax, or gelatin may be added to modify the precipitation. The traditional crimson color is affected not only by carminic acid but also by choice of its chelating metal salt ion. For shades of purple, lime is added to the alum.

To obtain 1 pound of red dye, one needs 70,000 cochineal bugs.

Properties and visual characteristics

Carminic acid structure

Thanks to liquid chromatography and a diode array detector combined with a mass spectrometer with a quadruple-time-of-flight analyzer (LC-DAD-QTOF), scientists can detect the presence of carminic acid. This further enables a better identification of works of art as it helps to determine the date and origin of the pigment.

Scientific methods now allow us to distinguish among the different species of cochineal used in artworks.

Wavelength

As confirmed by reflectance spectroscopy, carmine reflects mostly red light, i.e., wavelengths longer than about 603 nm. Its hue is comprised between 497 nm for a dark purplish red and 612 nm for a vibrant red.

Hue

The hue is the aspect of the color determined by wavelength. Carmine's hue is dependent on the metallic ions combined to cochineal while making the pigment. For instance, cochineal carmine and zinc or aluminum gives a crimson hue.

Translucence

The translucence of carmine depends on its binding medium. Mixed with oil, carmine remains translucent and adequate for glazes. Combined with tempera or glue, carmine turns opaque.

Value

The traditional hue's value is around 6.35, a yellowish hue 5.5, and a purplish hue 3.32.

Permanence

According to Russells' classification, carmine is the most unstable pigment. The hues of this red pigment, including "cochineal, carmine, and crimson lake" are very subject to fade into brownish tones.

Carmine is a fugitive color, whose fading is influenced by different factors such as light, humidity, or even the glass color of the frame.

In painting, its durability also depends on the type of binding. For instance, pigments are more resistant if mixed with linseed oil rather than with gum-arabic. Cochineal carmine is very sensitive to light in watercolor. Carmine can be stabilized "thanks to precipitation of cochineal-based red lake with alum, and thanks to the inclusion of tin salt mordants."

Notable occurrences in Art

Carmine's vibrant color is extensively used in Art and has been since its creation in Antiquity.

Carmine was used in dyeing textiles and in painting since antiquity. It is not very stable in oil paint, and its use ceased after new and better red pigments became available. Best examples of the use of carmine cochineal red are present among Inca remains such as textile artifacts. The Aztecs who occupied lands on the present Mexico also resorted to the female cocci's coloring power.

In Europe, the 16th century Italian painter Jacopo Tintoretto used carmine in several of his paintings. The most notable being Portrait of Vincenzo Morosini (1575-80) and Christ Washing the Feet of the Disciples.(1575-80)

Madame de Pompadour by Francois Boucher, French painter of the eighteenth century, extensively relies on cochineal. This is reminded in the pinkish color of the ribbons, the cameo, the dress, and Madame de Pompadour's pink cheeks as she is doing her make-up with cochineal based cosmetics. In this particular painting, cochineal is synonymous with femininity and high society.   

Carmine was also used by recent artists such as Vincent Van Gogh in Bedroom in Arles (1889). The once reddish floor of the bedroom is painted with carmine cochineal lake, geranium lake and indigo. Nowadays, the floor has lost its initial red color and is blueish because of the fugitive red pigments.

Joseph Mallord William Turner, a 19th century English painter used cochineal carmine as the analysis of his palettes revealed. The fading of this pigment affected his canvases changing his luminous reddish skies overtime as in The Fighting Temeraire (1839).

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  Tapestry shirt fragment, Peru, Chancay, c. 1000-1470 AD
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  Jacopo Tintoretto, Christ Washing the Feet of The Disciples (1575-80)
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  Jacopo Tintoretto, Portrait of Vincenzo Morosini (1575-80)
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  François Boucher, Madame de Pompadour (1750)
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  Vincent Van Gogh, Bedroom at Arles (1889)
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  JMW Turner, The Fighting Temeraire (1839)

Other major uses than Art

The use of red color, and more specifically carmine, is not constrained to the artistic field.

Sebastien Le Prestre de Vauban, Plan of Lille's Citadelle and harbour

Architecture

Carmine red is used in military cartography, at least since the 17th century with Sébastien Le Prestre Vauban, General Engineer of France, who recommended the use of this red pigment to resemble constructions (ramparts, wood timbers, brick buildings were reddish). This further made buildings distinct are first sight on plans.

Cosmetics

Carmine is present in numerous cosmetics for its red color. This has been used since since its discovery until now. For instance, it can be found in lipstick, eye shadow, nail polish. However, it may cause allergies.

Histology

Carmine can be used in histology, as Best's carmine to stain glycogen, mucicarmine to stain acidic mucopolysaccharides, and carmalum to stain cell nuclei. In these applications, it is applied together with a mordant, usually an Al(III) salt.^{[citation needed]}

Medicine

Cochineal, the insect used to make carmine cochineal, also has medical properties that were exploited by the Aztecs. It is said to help cure wounds when mixed with vinegar and applied to the lesion. Aztecs used it to clean teeth.

Now, indigo carmine is used to diagnose kidney potential dysfunction by coloring urine.

Regulations for use in foods

United States[edit]

In January 2006, the United States Food and Drug Administration (FDA) evaluated a proposal that would require food products containing carmine to list it by name on the ingredient label. It was also announced that the FDA will separately review the ingredient labels of prescription drugs that contain colorings derived from carmine. A request from the Center for Science in the Public Interest urging the FDA to require ingredient labels to explicitly state that carmine is derived from insects and may cause severe allergic reactions and anaphylactic shock was declined by the FDA. Food industries were aggressively opposed to the idea of writing "insect-based" on the label, and the FDA agreed to allow "cochineal extract" or "carmine".

In 2012, Starbucks had to replaced their cochineal colorant by a vegetal one, lycopene. Indeed, the cochineal colorant for present in drinks, but also cakes. This change was especially made for vegan and vegetarian customers.

European Union[edit]

In the European Union (EU), the use of carmine in foods is regulated under the European Commission's directives governing food additives in general and food dyes in particular and listed under the names Cochineal, Carminic acid, Carmines and Natural Red 4 as additive E 120 in the list of EU-approved food additives. The directive governing food dyes approves the use of carmine for certain groups of foods only and specifies a maximum amount which is permitted or restricts it to the quantum satis.^{[citation needed]}

The EU-Directive 2000/13/EC on food labeling mandates that carmines (like all food additives) must be included in the list of ingredients of a food product with its additive category and listed name or additive number, that is either as Food colour carmines or as Food colour E 120 in the local language(s) of the market(s) the product is sold in.^{[citation needed]}

As of January 2012, EFSA has changed the way they allow use of Carmine E120 for pharmaceutical products. The EFSA had raised concerns over the increasing number of allergic reactions to carmine derived from insects (E120.360), when used within the British Pharmacopoeia. Pharmaceutical products which had previously contained insect-derived carmine, have been replaced with a synthesized version of the food colorant. Internal studies have shown that the new formulations of popular anti-nausea and weight-gain liquid medication had a significantly lower risk in terms of allergic reactions.^{[citation needed]} The new formulation is known to be of plant origin, using calcium oxide to gauge color depth.^{[further explanation needed]}