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Why does this happen. When I mix milk with coke and let it sit, everything seperates out?

Clear liquid on top, with brown particulate matter on the bottom. Scientifically speaking, what is going on, and what is the solid matter that precipitates out?

I don't think I'm going to have any more Coca Cola!

Update:

Gerry D: LOL! No, it was an errant result of something kids were doing! LOL!

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  • 1 decade ago
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    It is a reaction of the Phosphoric Acid contained in the coca cola to the milk. Phosphoric Acid molecules attach to the milk giving them more density and separate out while the remaining liquid that makes up the milk and cocoa cola now being lighter floats on top. The solid matter is basically milk that has been curdled by the addition of the more acidic soda.

    Both items are acidic but coca-cola more so. In general, coca-cola has a pH of anywhere from 2.5-4.5 because of the Phosphoric Acid content where milk has a normal pH around 6.7 (almost neutral, milk that is in the base range is usually mastitic).

    There are some studies to suggest that because of the high Phosphoric Acid content in most soft drinks that they can help to increase the likelihood that a person will develop Osteoporosis if they aren't getting enough Calcium in their diet. Coca-cola makes an excellent household cleaner - it can be used to take tarnish off of pennies and I've used it to degrease car engines. I will not drink any soft drinks.

    Source(s): I'm a Chemical Process Engineer. I use Phosphoric Acid quite often in my job.
  • 4 years ago

    Milk And Coke

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  • 5 years ago

    Um, this experiment stinks. Coke and milk aren't in your stomach for 6 hours - and your stomach has hydrochloric acid in it, which is a stroger acid than that which is in Coke. It's not a reflection of what actually occurs in your body. Your body processes the Coke much more quickly. Drink a can and you're in the bathroom an hour later.

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  • 6 years ago

    A French Coke which we used to get in old time drug stores was half n half just a little added to fountain coke. It made a very tasty drink as do Coke Floats, but I don't know about all these chemical reactions. I'm, really not much of a soda drinker at all.

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  • 4 years ago

    What happens when you add water to hydrochloric acid? Since the only thing we are really designed to drink is water, and our stomachs contain hydrochloric acid, all the rest of this stuff is silly. Worry about the quality of your water, and don t drink anything else.

    Milk is good for you...if you are a baby cow.

    When in doubt, consider things from the point of view of what occurs in nature. Any time we fool with that we are monkeying with the natural order.

    That said, I m going to go drink a coke. I hope it kills me.

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  • 5 years ago

    Everybody is not quite right. read up on casein the protein that give milk its color. Casein is present as micelles, tiny lumps of casein (actually three forms). They float. But add acid, Coke, vinegar, hydrochloric, and the casein particles clump together and - sink. The attract the color as well. The colorless part in the middle is called whey. You know the poem "Little Miss Muffet ... eating her curds and whey?" So the protein precipitates in the highly acidic cola, leaving a clear liquid above and crud at the bottom.

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  • 6 years ago

    Everyone bashing the coke. A recent study on milk shows significant data that drinking milk after childhood increases your risk of heart decease and early death.

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    • John6 years agoReport

      Bullfuck. Correlation is not causation. Not to mention that the correlation is statistically insignificant.

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  • 6 years ago

    This is a systemic chemical reaction of the Lactic Acid penetrating the auto-osmosis of the Cocoa nucleic membrane that exchanges aerated micro-enzymes with the plastic surface of the bottle. It's really quite simple.

    • 6 years agoReport

      I have a strong belief that you have no Idea what you're talking about, because it was all incorrect.

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  • 6 years ago

    Good grief. I am 56 years old, and have drank my fair share of cokes over the years. I now only have an occasional fountain coke, but I am not losing sleep over this. I had to chuckle, this made me think of the show Laverne and Shirley, because Laverne's favorite drink was milk and Pepsi.

  • 6 years ago

    I don't care why this happens. I use Coke to clean the rust off my car, so I certainly will not want to drink it.

    • Felix6 years agoReport

      You can also remove rust with lemon juice and salt. Lime juice, ketchup and white vinegar also work.

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  • 1 decade ago

    The same thing will happen if you add lemon juice to milk, or if the milk turns sour (homogenised milk usually turns mouldy first)

    The protein particles in the milk have negative charges on their surfaces, because of weakly acidic groups in the proteins. These charges repel each other, so the particles don't stick together. If you add acid (and there is enough acid in Coke) this neutralises the surface charges, and the particles clog together. This process is called "flocculation".

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