Cochineal
The cochineal (/ˌkɒtʃɪˈniːl/ KOTCH-ih-NEEL, /ˈkɒtʃɪniːl/ KOTCH-ih-neel; Dactylopius coccus) is a scale insect in the suborder Sternorrhyncha, from which the natural dye carmine is derived. A primarily sessile parasite native to tropical and subtropical South America as well as Mexico and the Southwest United States, this insect lives on cactiin the genus Opuntia, feeding on plant moisture and nutrients. The insects are found on the pads of prickly pear cacti, collected by brushing them off the plants, and dried.[vague]
The insect produces carminic acid that deters predation by other insects. Carminic acid, typically 17-24% of dried insects’ weight, can be extracted from the body and eggs, then mixed with aluminium or calcium salts to make carmine dye, also known as cochineal. Today, carmine is primarily used as a colorant in food and in lipstick (E120 or Natural Red 4).
The carmine dye was used in Central America in the 15th century for coloring fabrics and became an important export good during the colonial period. After synthetic pigments and dyes such as alizarin were invented in the late 19th century, natural-dye production gradually diminished. Health fears over artificial food additives, however, have renewed the popularity of cochineal dyes, and the increased demand has made cultivation of the insect profitable again,[1] with Peru being the largest exporter. Some towns in the Mexican state of Oaxaca are still working in handmade textiles using this cochineal.[2]
Other species in the genus Dactylopius can be used to produce “cochineal extract”, and are extremely difficult to distinguish from D. coccus, even for expert taxonomists; that scientific term from the binary nomenclature, and also the vernacular “cochineal insect”, are thus commonly used[vague] when one[specify] is actually (whether intentionally or casually, and whether or not with misleading effect) referring to other biological species. (The primary biological distinctions between species are minor differences in host plant preferences, along with very different geographic distributions.)
Cochineal use in histology: Carmine staining of a monogenean (parasitic worm)
Traditionally, cochineal was used for colouring fabrics. During the colonial period, with the introduction of sheep to Latin America, the use of cochineal increased, as it provided the most intense colour and it set more firmly on woolen garments than on clothes made of materials of pre-Hispanic origin such as cotton or agave and yucca fibers. In general, cochineal is more successful on protein-based animal fibres (including silk) than plant-based material. Once the European market discovered the qualities of this product, the demand for it increased dramatically. By the beginning of the 17th century, it was traded internationally.[7] Carmine became strong competition for other colourants such as madder root, kermes, Polish cochineal, Armenian cochineal, brazilwood, and Tyrian purple,[29] as they were used for dyeing the clothes of kings, nobles, and the clergy. For the past several centuries, it was the most important insect dye used in the production of hand-woven oriental rugs, almost completely displacing lac.[7] It was also used for painting, handicrafts, and tapestries.[9] Cochineal-coloured wool and cotton are important materials for Mexican folk art and crafts.[30][31]
Cochineal is used as a fabric and cosmetics dye and as a natural food colouring. It is also used in histology as a preparatory stain for the examination of tissues and carbohydrates.[32] In artists’ paints, it has been replaced by synthetic reds and is largely unavailable for purchase due to poor lightfastness. Natural carmine dye used in food and cosmetics can render the product unacceptable to vegetarian or vegan consumers. Many Muslims consider carmine-containing food forbidden (haraam) because the dye is extracted from insects and all insects except the locust are haraam in Islam.[33] Jews also avoid food containing this additive, though it is not treif, and some authorities allow its use because the insect is dried and reduced to powder.[34]
Cochineal is one of the few water-soluble colourants to resist degradation with time. It is one of the most light- and heat-stable and oxidation-resistant of all the natural organic colourants and is even more stable than many synthetic food colours.[35] The water-soluble form is used in alcoholic drinks with calcium carmine; the insoluble form is used in a wide variety of products. Together with ammonium carmine, they can be found in meat, sausages, processed poultry products (meat products cannot be coloured in the United States unless they are labeled as such), surimi, marinades, alcoholic drinks, bakery products and toppings, cookies, desserts, icings, pie fillings, jams, preserves, gelatin desserts, juice beverages, varieties of cheddar cheese and other dairy products, sauces, and sweets.[35]
Carmine is considered safe enough for cosmetic use in the eye area.[36] A significant proportion of the insoluble carmine pigment produced is used in the cosmetics industry for hair- and skin-care products, lipsticks, face powders, rouges, and blushes.[35] A bright red dye and the stain carmine used in microbiology is often made from the carmine extract, too.[17] The pharmaceutical industry uses cochineal to colour pills and ointments.[22]
