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I have been consuming oranges lately, and I have noticed that the skin of the oranges I had were too smooth and shiny (looked very much like plastic or some kind of laminated orange peel). I was very concerned about this and tried a couple of experiments on the peels. I tried to rub the peel with water for the first test, but no colouring came off. However, after rubbing the peel with detergent (knowing that it was both hydrophobic and hydrophilic) , a thin white layer of some kind of hard, plastic-like material formed, encrusting the orange peel. I will be conducting experiments on other types of oranges to check whether if it applies to most of the common oranges or just this type that I have.
I believe that its the food colouring agent... it may be carcinogenic..
Thank you in advance!
-P.S this is my first post!!
What do orange peels contain (or made out of)?
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svenrei
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- Project Question: Need to identify harmful substances (hydrophobic chemicals) used to coat orange peels.
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deleted-137717
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Re: What do orange peels contain (or made out of)?
Hi svenrei,
Definitely interesting. You're right that food coloring agents are in fact sometimes used to artificially color orange peels. If you're applying the same method to other oranges, and since you suspect the substance to be the food coloring additive, be sure to include some USDA-Certified Organic oranges. The certification process doesn't allow food dyes.
Definitely interesting. You're right that food coloring agents are in fact sometimes used to artificially color orange peels. If you're applying the same method to other oranges, and since you suspect the substance to be the food coloring additive, be sure to include some USDA-Certified Organic oranges. The certification process doesn't allow food dyes.
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SciB
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Re: What do orange peels contain (or made out of)?
Hi Sven,
Interesting observation about the substance on the oranges, but be careful about jumping to the idea that it may be carcinogenic. It sounds to me like a wax that is sprayed onto the fruit to inhibit the growth of mold. A dye for oranges would most likely be oil-soluble and penetrate the peel to color the orange, but would not come off in plastic-like bits. People don't usually eat orange peel, so the USDA rules may be different from those for a fruit like apples where people often do eat the peel.
In addition to organic oranges as cbrambley suggested, I would try your detergent on apples, cucumbers, squash or any other fruit or vegetable that looks like it was dyed or waxed. Do some searching online for how fruits and vegetables are dyed, waxed or treated with a preservative before they are marketed.
Most chemicals that are used on or in our food have been tested for carcinogenicity and are safe. There are biological ways to test for mutagenicity if you are interested.
Post again with your plans for a project and we can help you with the design and execution.
Sybee
Interesting observation about the substance on the oranges, but be careful about jumping to the idea that it may be carcinogenic. It sounds to me like a wax that is sprayed onto the fruit to inhibit the growth of mold. A dye for oranges would most likely be oil-soluble and penetrate the peel to color the orange, but would not come off in plastic-like bits. People don't usually eat orange peel, so the USDA rules may be different from those for a fruit like apples where people often do eat the peel.
In addition to organic oranges as cbrambley suggested, I would try your detergent on apples, cucumbers, squash or any other fruit or vegetable that looks like it was dyed or waxed. Do some searching online for how fruits and vegetables are dyed, waxed or treated with a preservative before they are marketed.
Most chemicals that are used on or in our food have been tested for carcinogenicity and are safe. There are biological ways to test for mutagenicity if you are interested.
Post again with your plans for a project and we can help you with the design and execution.
Sybee