heasliponline01
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Chemistery experiment on fruits
If I add alcohol, can I find out if the fruits I am buying are contaminated with chemical insecticides?
I just saw a tv show and I always actually wondered about how do the fruits last so long in the market, compared to the ones from my grandma's tree,
and I am almoust convinced that even if I wash up the fruits, there would be still some poisoning chemical left. Any advices?
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Fantasma4500
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there is something with ethene forming in fruits that makes them rot, supposing there are things added to the fruits that eliminates the ethene thus
making it last longer
GMO should also be considered
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Texium
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They often pack bananas with potassium permanganate during shipping to absorb the ethylene that they produce, keeping them from ripening. Then they
give the bananas a heavy dose of ethylene to induce ripening just before delivery to the supermarkets.
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Etaoin Shrdlu
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No. You could buy organic if you're worried.
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blazeriggins127
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that's obvious
I think is a very good topic and if everybody knew how to do this experiment at home they would be amazed by what we intake in our bodies.. It is
obvious that there is an amount of insecticides left in the fruits, but some of those chemical are deadly and it is good to do a basic experiments
with fruits bought from different stores, so you could find out where are healthier alternatives in fruits and vegetables. The process is not easy to
do at home thou, espoecially for people who are not really into chemistry, but there are various solvents you could use such as chloroform, acetone,
acetonitrile and methanol.
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MrHomeScientist
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While this would certainly make an interesting experiment or science fair project, to me it sounds just a bit too paranoid. I, and most everyone I
know, has been eating fruit all their lives and nobody's dropped dead from biting into an apple containing minute traces "boogeyman chemicals."
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confused
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if you want to do it, i suggest rinsing the fruits in a solvent (ethanol+water mix .etc) and concentrating it, analysis could be a problem, TLC might
work, not very sure
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CHRIS25
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Quote: Originally posted by MrHomeScientist ![](images/xpblue/lastpost.gif) | While this would certainly make an interesting experiment or science fair project, to me it sounds just a bit too paranoid. I, and most everyone I
know, has been eating fruit all their lives and nobody's dropped dead from biting into an apple containing minute traces "boogeyman chemicals."
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Well I certainly do not have any knowledge in this field, but there is one recurring fact that slips through many a scientific program or journal that
I read and that is this: Some chemicals can take years and years to show any effects, on top of this there are those other "boogyman" things that
compound the whole problem when the human body is synthesizing a multitude of chemicals together, mixed, that have effects not even understood today,
and one more fact, it can even take a generation for the build up of such things which will have no effect on the person digesting it, but on their
children's DNA that then gets passed on. The world is awash with medical problems, I am certain our food has and does play a significant role.
Having said that I am eating a banana right now
‘Calcination… is such a Separation of Bodies by Fire, as makes ‘em easily reducible into Powder; and for that reason ‘tis call’d by some
Chymical Pulverization.’ (John Friend, Chymical Lectures London, 1712)
Right is right, even if everyone is against it, and wrong is wrong, even if everyone is for it. (William Penn 1644-1718)
The very nature of Random, Chance development precludes the existence of Order - strange that our organic and inorganic world is so well defined by
precision and law. (me)
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Tsjerk
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Could you explain how the experiment is preformed?
My first thoughts are that the methods they use to keep the fruit fresh (not ripe) for a longer period of time are, as mentioned before, by keeping
ethylene out.
A quite famous experiment is to have fruit from the exact same source in four conditions.
1. a ventilated environment, not touching,
2. a ventilated environment, touching,
3. a not ventilated environment, not touching,
4. a not ventilated environment, touching.
In conditions 2, 3 and 4 the fruit will decay faster.
An important control is (1) the addition of ethylene to a single piece of fruit in a not ventilated environment and the same piece of fruit (2) in the
same environment without addition of ethylene.
In the control environments, number 1 will decay, while number 2 won't.
Fruits want to mature at the same time to make their distribution by animals more likely (more change of attracting animals together than by
themselves). They do this by producing ethylene when becoming ripe, and becoming ripe when sensing ethylene, a positive feedback loop.
Because of these experiments one could conclude the altering of the natural process is not harmful to the animal eating the fruit, as nothing is
added. The fruit won't change in any way by capturing the ethylene, even when ethylene is added to make the fruit ripen afterwards.
I'm really curious about the experiment you saw on TV though.
[Edited on 14-4-2014 by Tsjerk]
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