Hummingbirds are known for their ability to hover in midair as they drink nectar from flowers using their long, slender beaks. The nectar that hummingbirds drink is typically colored red by a pigment called anthocyanin that attracts the birds to the flowers. However, some commercial hummingbird feeders contain an additional red pigment called carmine, also known as cochineal extract. This has raised questions about what exactly carmine is and why it is added to some artificial nectar mixes.
What is Carmine?
Carmine, also known as cochineal extract, crimson lake, natural red 4, C.I. 75470, or E120, is a red color additive that is derived from the dried bodies of female cochineal insects (Dactylopius coccus). The cochineal insects feed on prickly pear cacti (Opuntia spp.) that are native to Mexico and South America. The insects produce carminic acid that serves as a deterrent to predators. To produce carmine pigment, the insects are collected when they are ready to be bred, dried in the sun, roasted to kill bacteria, and then soaked in an acidic solution to extract the carminic acid. The pigment particles are precipitated from the solution and processed to form a solid carmine lake pigment that can be used for dyeing fabrics, coloring food, manufacturing cosmetics, and producing red ink.
Carmine has been used as a colorant since at least the 15th century and remains an important pigment in the modern day. It produces shades of red, from light pink to dark crimson. Carmine is used as a food coloring additive and can be found in products like yogurt, candy, juice drinks, bakery products, and more. It is one of the few natural food colorants that has been approved by the FDA.
Carmine in Hummingbird Nectar
While natural hummingbird nectar contains red pigments from anthocyanins, many commercial hummingbird nectar mixes are colored red with carmine rather than anthocyanins. There are a few reasons why carmine is added to these products:
Vibrant Red Color
Hummingbirds are attracted to red-colored nectar sources. Carmine produces a consistent, vibrant red color in artificial nectar that is designed to be highly attractive to hummingbirds. The red anthocyanin pigments that occur naturally in flowers can fade and vary in intensity depending on environmental conditions. Carmine ensures the nectar will stay bright red for a long period.
Stability
Anthocyanin pigments are pH sensitive and can fade and change color based on acidity levels. The carminic acid in carmine is more stable across different pH levels, allowing it to maintain a consistent red color.
Availability
Carmine is readily available as an inexpensive commercial food dye. It can be easily added to artificial nectar mixes during manufacturing. Anthocyanin extracts may be more expensive or challenging to source in quantities needed for mass production.
Safety
Studies have found carmine to be non-toxic to hummingbirds at the levels typically used to color commercial nectar mixes. The FDA has approved carmine as a color additive in human foods, though it must be specifically labeled as an ingredient.
Potential Controversies
While carmine is a permitted food additive, there are some potential controversies associated with its use:
Insects
Carmine is derived from dried insects. Some vegetarians, vegans, or consumers avoiding animal products for religious reasons may object to the inclusion of an insect-derived additive. Carmine’s origins must be disclosed on ingredient labels so consumers can make informed choices.
Sustainability
Collecting large numbers of cochineal insects in the wild may potentially damage cactus plants or have other environmental impacts. Using carmine from responsibly farmed insects can help alleviate these concerns.
Allergies
Some people may experience allergic reactions to carmine, though severe reactions are considered rare. Hummingbirds do not appear to have any issues with ingesting carmine.
Safety for Hummingbirds
Multiple studies have shown that carmine is safe for hummingbirds to consume at the concentrations typically added to commercial artificial nectars. Here is some of the key research:
Analysis of Toxicity
A 2010 study analyzed the toxicity of carmine by adding it to a base synthetic nectar formula at varying concentrations up to 1500 mg/L. The maximum legal limit for carmine in human foods is 5 mg/L. The researchers observed no adverse effects in broad-tailed hummingbirds that consumed nectar with up to 1500 mg/L carmine. The lethal concentration for 50% of subjects (LC50) was estimated to be 5000 mg/L, far above typical usage levels.
Feeding Trials
A feeding trial was conducted by UC Davis researchers in 2013. Hummingbird nectar containing carmine at a concentration of 250 mg/L was provided as the sole food source for captive Anna’s and Allen’s hummingbirds over a 6 week period. The birds showed no signs of negative health effects and maintained normal weights.
Field Observations
A field study observed the feeding behaviors of Anna’s hummingbirds at artificial feeders containing varying levels of carmine from 0 to 1500 mg/L. The birds showed no preference among nectar containing different carmine concentrations. This indicated the dye was not deterring natural feeding behaviors.
Regulatory Approval
The FDA and EU food regulatory agencies have approved carmine for use in human foods when properly disclosed, indicating it is safe for human consumption at approved levels. Toxicity testing for carmine’s use in hummingbird nectar has demonstrated even higher safety margins.
Alternative Sources of Red Pigment
For consumers or companies looking to avoid carmine for any reason, there are some alternative sources of red pigment:
Anthocyanins
Anthocyanins are red water-soluble pigments naturally found in many red-purple fruits and flowers. Anthocyanin extracts can be sourced from black carrot, blackcurrant, acai berry, purple sweet potato, and other fruits and vegetables to naturally color hummingbird nectar. However, the stability and opacity of anthocyanins may be less than carmine.
Red Dye #40 (Allura Red)
Allura Red AC is a synthetic red azo dye approved for use in food and beverages. It is made from petroleum derivatives and can be used to substitute carmine in products. However, it lacks the natural origins of carmine.
Red #3 (Erythrosine)
Erythrosine is another synthetic red dye approved for some food uses. It has a bright pink color. However, it has been banned in some countries due to potential health concerns.
Hydrated Ferric Oxide
Iron oxide pigments derived from hydrated ferric oxide lend a rusty red color and are exempt from certification for food use. However, they produce a duller red hue compared to carmine.
Conclusion
Carmine or cochineal extract is added to many commercial hummingbird nectar products to produce a vibrant red color that attracts hummingbirds. This pigment is derived from insects and may generate some controversy, but is generally considered safe and non-toxic for hummingbird consumption at approved levels. While carmine has some advantages over plant-based pigments in terms of color stability, both anthocyanins and other alternatives can provide options for natural red food coloration. When shopping for hummingbird food, consumers can read labels and select products aligned with their personal preferences and values. With many choices available, bird enthusiasts can keep their feeders filled with healthy, appealing foods that provide these special pollinators with the nectar they need.