Naked Science Forum
Non Life Sciences => Chemistry => Topic started by: neilep on 03/02/2012 16:12:32
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Hullo,
See this oil:
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nice eh ?....bit cloudy though !...like the weather !
now see this same oil a few minutes later !
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WOW !!...the very same oil just a few minutes later !!
Before .......it was cold...then i zapped it in the microwave for a few seconds ....and so...... after.......it became clear !...WOW !!
Can we do that with a cloudy day ?
So...why is le cold oil cloudy and le warm oil clear ?
Ewe see...I just don't know but I want to know !....please help me know !
hugs and shmishes
mwah mwah mwah
Neil
Oil Enquirer
xxxxxxxxxx
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The first piccy looks suspiciously like orange juice.
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The first piccy looks suspiciously like orange juice.
Hang On !!...ewe mean to say cold olive oil turns into orange juice below a certain temperature !!....well.......I'm convinced !!...WOW !!..that's even more astonishing !
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Yes.
You didn't happen to notice Yuri Geller hiding in your fridge, by any chance?
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So...
You've discovered one of the big problems with biodiesel.
In theory you can cold filter (or perhaps centrifuge) the oil, and separate out high melting point and low melting point constituents.
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So...
You've discovered one of the big problems with biodiesel.
In theory you can cold filter (or perhaps centrifuge) the oil, and separate out high melting point and low melting point constituents.
or, you could move to Arizona, or even Greece! (You might even be able to pick up an inexpensive island at the moment.)
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On an almost related topic. I have discovered that if you drop olives into liquid olive oil, within a few days the oil turns white and sets solid. Why's that then?
I don't think this is a new theory Geezer so there is probably no need to move it to "New Theories" but better safe than sorry perhaps?
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On an almost related topic. I have discovered that if you drop olives into liquid olive oil, within a few days the oil turns white and sets solid. Why's that then?
Could it be the salt used to cure the olives has some effect on the oil?
BTW, did you know Olive Oil should not be stored in plastic bottles as the PCV's can leach into the oil?
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BTW, did you know Olive Oil should not be stored in plastic bottles as the PCV's can leach into the oil?
I think you also want to keep it out of ultraviolent light (probably clockwork oranges too.)
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http://www.oliveoilsource.com/page/freezing-olive-oil
That is for the first part
On an almost related topic. I have discovered that if you drop olives into liquid olive oil, within a few days the oil turns white and sets solid. Why's that then?
I think this is because the oil get saturated
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On an almost related topic. I have discovered that if you drop olives into liquid olive oil, within a few days the oil turns white and sets solid. Why's that then?
Could it be the salt used to cure the olives has some effect on the oil?
BTW, did you know Olive Oil should not be stored in plastic bottles as the PCV's can leach into the oil?
What are PCVs?
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I think MikeS means PVC
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I wondered about that, but B and V are next to each other on the keyboard and I wondered if he meant PCBs.
However, since PVC is insoluble and PCBs shouldn't be in the packaging for food it still didn't make sense.
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What is being observed is simply a form of freezing and melting.
"Olive oil", even the highest grade of olive oil (which this sample does not appear to be) is not a pure chemical compound but a mixture. It therefore melts and freezes over a temperature range of several degrees.
When it starts to freeze (top of the freezing range), tiny solid particles in the 99% liquid material produce a cloudy appearance.
At a slightly lower temperature there is enough solid to form a gel (solid cage-like framework with free-flowing liquid channels), and this produces the "biodiesel problem" (although there is probably also some polymerization in that case, which is much more problematic because it is irreversible -- it will not fix itself up when the material is warmed). And of course at a lower temperature again, the whole thing freezes solid.
The best quality olive oil comes in glass containers. But when plastic containers are used there is unlikely to be a leaching problem. Plastic containers for materials like olive oil are almost certainly made of polyethylene or poly(ethylene terephthalate).
PVC should not be used for food storage. It is quite insoluble, and PVC cannot leach into anything, but PVC needs to contain a plasticizer (supposedly inert liquid) to change it from a brittle glassy material to a typical flexible plastic, and plasticizer can leach out. A typical and widely used plasticizer is dioctyl phthalate:
http://en.wikipedia.org/wiki/Bis(2-ethylhexyl)_phthalate (http://en.wikipedia.org/wiki/Bis(2-ethylhexyl)_phthalate)