Works Cited
- Carocho, Marcio. "Adding Molecules to Food, Pros and Cons: A Review on Synthetic and Natural Food Additives." Comprehensive Reviews in Food Science and Food Safety 13.4 (2014): 377-99. Print.
- Cemek, Mustafa. "Effects of Food Color Additives on Antioxidant Functions and Bioelement Contents of Liver, Kidney and Brain Tissues in Rats." Journal of Food and Nutrition Research 2.10 (2014): 686-91. Web. <http://pubs.sciepub.com/jfnr/2/10/6/jfnr-2-10-6.pdf>.
- Ebadi, Farshid. "Evaluation of Antioxidant Activity of Safflower Florets (Carthamus Tinctorius L.) as Food Coloring Agents." Journal of Chemical and Pharmaceutical Research, 2014, 6(8):539-544 (2014): n. pag. Web. <http://jocpr.com/vol6-iss8-2014/JCPR-2014-6-8-539-544.pdf>.
- Kobylewski, Sarah, and Michael Jacobson. "Food Dyes a Rainbow of Risks." Center For Science in the Public Interest (2010): n. pag. Web. <http://cspinet.org/new/pdf/food-dyes-rainbow-of-risks.pdf>.
- McCann, Donna, Mix A For 3-Year-Old Children Included 20 Mg Of Artificial, and Fo. "Articles Food Additives and Hyperactive Behaviour in 3-year-old and 8/9-year-old Children in the Community: A Randomised, Double-blinded, Placebo-controlled Trial." The Lancet (2007): n. pag. 6 Sept. 2007. Web. <http://www.cspinet.org/new/pdf/mccann.pdf>.
- Potera, Carol. "DIET AND NUTRITION: The Artificial Food Dye Blues." National Center for Biotechnology Information. U.S. National Library of Medicine, Oct. 2010. Web. 25 Oct. 2014. <http://www.ncbi.nlm.nih.gov/pmc/articles/PMC2957945/#!po=50.0000>.
- Sarikaya, Rabia. "Evaluation of Potential Genotoxicity of five Food Dyes Using the Somaticmutation and Recombination Test." Chemosphere 88 (2012): 974-79. Web. <http://www.academia.edu/4003229/Food_dye_mutagenesis>.
- Standberg, Moa. "Food Coloring Influences Taste and Flavor Perception." Food Coloring Influences Taste and Flavor Perception (n.d.): n. pag. 2014. Web. <http://www.ungaforskare.org/sites/default/files/files/food_coloring_influences_taste_and_flavor_perception.pdf>.
Classroom Applications:
- Explore natural colorants, look at the effects of temperature and pH on these compounds (cabbage lab is great for pH).
- Explore the enzyme azo reductase. How do the enzyme and substrate interact and what are the ideal conditions for this enzyme (temp, pH)?
- What is the role of the microbiota in our gut? Food colorings are often broken down by the microflora in our gut, what else do these bacteria do? What beneficial effects do they have? Any harmful effects?
- What makes something carcinogenic? Explore the biology of cancer and why certain chemicals disrupt the cell cycle.
- Explore the neurology of taste and its connection to sight. Is our sense of taste really affected by the color we see on our plate, in our cups? Design an experiment to test this idea.
food coloring
- This type of dye includes quinoline yellow. This is a synthetic dye made by mixing sodium disulfonates, monosulfonates and trisulfonates.
- It has been reported to cause asthma, rashes and hyperactivity.
- The ADI (Allowed Daily Intake) is 10 mg/kg.
Categories of Food Additives
Kathryn Davis
Image: https://pubchem.ncbi.nlm.nih.gov/compound/6731?from=summary#section=Top
http://onlinelibrary.wiley.com/doi/10.1111/1541-4337.12065/full
http://onlinelibrary.wiley.com/doi/10.1111/1541-4337.12065/full
These three food colorings make up 90% of the dyes used in the United States!
Amaranth is also derived from petroleum. It was banned in the U.S. for allegedly being carcinogenic, but it is still allowed in the European Union. The ADI for this chemical is only 0.5 mg/kg
http://www.academia.edu/4003229/Food_dye_mutagenesis
These colors contain the functional group R-N=N-R where "R" is an aryl or alkyl.
Examples include:
- tartrazine (yellow No. 5)
- sunset yellow (yellow No. 6)
- allure red (red No. 40)
- amaranth
- carmosine
Azo dyes can be reductively cleaved into aromatic amines, and some of these amines are toxic, mutagenic, and/or carcinogenic.
Azo dyes can be reduced to aromatic amines by intestinal microflora, and possibly the enzyme azo reductase found in the liver. The products of this reduction are semiquinone radicals and aromatic amines.
Erythrosine (Red No. 3) ADI 0.1 mg/kg
used in maraschino cherries, sausage casings, oral drugs and candies
Others in this group:
- Fluoresceine-banned in the EU, related to altering childhood behavior and thyroid function due to high iodine content
- eosine
- thodamine
Allura red (Red 40) was shown to have affects on memory and learning in rats.
The ADI for allura red is 7 mg/kg/day
Sunset yellow (Yellow No. 6) comes from aromatic compounds that are derived from petroleum hydrocarbons.
It has been related to genotoxicity and memory and learning deficits in rodent models.
Yellow 6 is reduced at the azo linkage by gut microflora to make sulfanilic acid and 1-amino-2-naphthol-6-sulfonic acid.
The ADI is 2.5 mg/kg
It is use in bakery goods, cereals, beverages, dessert powders, candies, gelatin desserts, sausage, other foods, cosmetics and drugs.
Red 40 is used in beverages, bakery goods, dessert powders, cereals, many other foods, drugs and cosmetics.
The dye is broken down by gut microflora via azo-reduction into cresidine-4-sulfonic acid and 1-amino-2-naphthol-6-sulfonic acid.
Cresidine is "possibly carcinogenic to human" according to the U.S. National toxicology program.
Tartrazine (Yellow No. 5) is particularly controversial.
-Some studies have shown it to be a DNA binder, toxic to lymphocytes, a contributor to cirrhosis, among other negative effects!
-Another study which looked at the effects of both tartazine and carmosine showed that they affected and altered the bioelement levels in the liver, kidney and brain.
-Specifically iron and zinc contents of the liver, kidney and brain changed significantly. This could lead to iron deficiency or anemia and zinc deficiency has been known to cause hyperactivity and other behavioral changes.
-The Acceptable Daily Intake (ADI) for this dye is 5 mg/kg
-This dye is used in products such as chips, soft drinks, cakes, ice creams, gelatin desserts, pet food, pharmaceuticals, cosmetics, soap, and shampoo
http://cspinet.org/new/pdf/food-dyes-rainbow-of-risks.pdf
http://onlinelibrary.wiley.com/doi/10.1111/1541-4337.12065/full
http://cspinet.org/new/pdf/food-dyes-rainbow-of-risks.pdf
http://pubs.sciepub.com/jfnr/2/10/6/jfnr-2-10-6.pdf
http://cspinet.org/new/pdf/food-dyes-rainbow-of-risks.pdf
http://onlinelibrary.wiley.comdoi/10.1111/1541-4337.12065/full
Images: http://cspinet.org/new/pdf/food-dyes-rainbow-of-risks.pdf
why is food coloring used?
http://pubs.sciepub.com/jfnr/2/10/6/jfnr-2-10-6.pdf
http://onlinelibrary.wiley.com/doi/10.1111/1541-4337.12065/full
http://cspinet.org/new/pdf/food-dyes-rainbow-of-risks.pdf
Food coloring has long been used to enhance the appearance of food. But is this chemical additive necessary for use in food? Synthetic food coloring has no nutritional value and many believe these dyes should be removed from the food system. Let's explore the chemistry behind these brightly colored molecules...
Food additives have been around for a long time as a way to preserve food and to enhance flavor.
Food additives became especially common when citizens became less involved in the cultivating and processing of the food they eat, and food had to be processed and shipped before reaching the consumer.
- Specifically food coloring is used to:
- enhance the natural color of foods
- add "fun" color to otherwise colorless foods (imagine a Cheetoh that looked like a gray larvae, would you eat it?)
- make food more attractive and appetizing
- allow products to be identified by sight, such as the dose of a medication
there is conflicting
Indigo dye (Blue No. 2)
- Comes naturally from a shrub (indigofera tinctoria) but is also chemically produced.
- Adverse reactions rarely occur with this dye.
- used for beverages, candies, pet foods
- ADI is 2.5 mg/kg
Examples:
- Brilliant blue (blue No. 1) ADI 12.5 mg/kg
- Fast green-banned in the EU ADI 12.5 mg/kg
- Patent blue-banned in the U.S. ADI 1 mg/kg
- Brilliant black- ADI 1 mg/kg
These dyes are not readily absorbed by our bodies. Some reports showed changes in mitochondrial respiration caused by this group and others showed mutations in a wing spot test in Drosophila melanogaster.
There is concern about blue lollipops due to potential absorption of the dye to the lingual mucosa.
Many studies provide inadequate testing methods, including a lack of in utero exposure.
Three most common
evidence
In 2010 the Center for Science in the Public Interest (CSPI) published the report: Food Dyes, a Rainbow of Risks.
This report pointed out the nine dyes approved in the United States are likely carcinogenic, cause hypersensitivity reactions and behavioral problems, or are inadequately tested.
Many studies were found to use relatively small numbers of animals and did not include in utero data.
Rodent studies often lasted 2 years, but cancer in rodents doesn't usually show up until 3 years.
Additionally, the most commonly used dyes (Red 40, Yellow 5 and 6) contain benzidene, a human carcinogen. Most benzidene is bound, but the FDA only measures free benzidene. Intestinal bacteria can free the bound benzidene when ingested...so the exposure may be greater than we are aware of.
Few studies consider combinations of dyes that are often seen in foods. For example, Kellogg's Hot Fudge Sundae Pop Tarts contain Blue 1, Blue 2, Red 40, Yellow 5 and Yellow 6!
http://cspinet.org/new/pdf/food-dyes-rainbow-of-risks.pdf
In 2007, the controversial "Southhampton Study" gave a cocktail of food coloring to children in two age groups.
-153 three-year-olds
-144 eight-year-olds
- The children were given the drink each day (which contained several food colorings and benzoate, a preservative) and compared to a placebo group who had regular fruit juice.
- The children in the experimental group demonstrated evidence of increased ADHD.
- findings were worrying, but didn't show causation.
As early as 1970, Benjamin Feingold observed hyperactivity could be caused by food dyes.
http://www.academia.edu/4003229/Food_dye_mutagenesis
http://www.cspinet.org/new/pdf/mccann.pdf
Studies regarding genotoxicity show conflicting information. Yellow No. 5 shows genotoxicity in over 50% of studies!
http://onlinelibrary.wiley.com/doi/10.1111/1541-4337.12065/full
further in depth studies are needed!
http://cspinet.org/new/pdf/food-dyes-rainbow-of-risks.pdf
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC2957945/#!po=50.0000
http://cspinet.org/new/pdf/food-dyes-rainbow-of-risks.pdf
http://cspinet.org/new/pdf/food-dyes-rainbow-of-risks.pdf
and other interesting tidbits!
Discussion questions
Why not go all natural?
Interesting Uses
- Citrus Red (Red No. 2) is only permitted for coloring the skin of oranges
- Orange B is approved only for use in hot dogs and sausage casings
Interested in making your own natural food colors? check out the video!
United States vs other countries
There is increased pressure for natural colors such as carotenoids, anthocyanins, annatto, paprika, beet juice and turmeric
Natural colorants can even be beneficial to our health, like safflower extracts and their antioxidants which can fight disease causing free radicals!
BUT...
- natural colors are unstable due to pH and temperature changes
- show loss of color from oxidation
- need higher quantities to compare to the color of chemical dyes
- have a higher cost of manufactering
- In the U.K. Fanta orange soda is colored with pumpkin and carrot extracts, in the U.S. it is colored with Red 40 and Yellow 6.
- In Britain, McDonald’s strawberry sundaes are colored only with strawberries, but Red 40 is used in the United States.
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC2957945/#!po=50.0000
1. Do the benefits of food coloring outweigh the risks? Do you support the use of food coloring in general?
2. Have you tried to use natural food coloring at home? Things like frosting just wouldn't be as fun without a little color, have you tried coloring them naturally?
3. Look around your house, what foods can you find that contain food coloring? Is it more or less prevalent in your own home than you thought?
4. What do you think it will take to change a place like McDonald's (who already uses natural food coloring in Britain) to use natural food coloring in the United States? Will it ever happen?
5. Our senses, sight and smell interact to create a "flavor" in our minds (along with our sense of taste). What is the role of each, which one is most influential on our sense of taste: sight or smell?