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What's the deal with esters?

  1. May 28, 2005 #1

    ShawnD

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    I've made some 85% alcohol (tested with a hydrometer), and it's much more reactive than normal booze. If you mix tequila with lemon juice, it will take a few hours before you get esters happening. My booze is fast; it starts forming esters within 10 minutes, and it's hard to drink a whole margarita in 10 minutes without slamming it. When esterification starts happening, is my booze essentially gone forever or will it break down into usable alcohol after I eat/drink it?
     
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  3. May 28, 2005 #2

    GCT

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    I've never really understood why people make their own alcohol for drinking purposes. I would highly disadvise it. Anybody know if there is a particular reason why lemon juice is added to tequilla, or is it just for taste?

    Perhaps protonation of the ester (due to the acidity) might bring back the alcohol in a series of steps, but I don't quite remember where alcohol is absorbed and other important particulars of this subject, mostly pertaining to the biological aspects.
     
  4. May 28, 2005 #3

    ShawnD

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    People make it because it's cheap, tastes better, and it's safer.
    750mL of 40% from the store costs $20, but making 2L of 80% costs $5.
    It tastes better because alcohol and water are both tasteless; the garbage taste of store alcohol is added just to piss people off (imo).
    Home made booze is safer than wine because refined sugar has only 1 product: ethanol. Wine, or derivatives of wine (store booze), are made from fruits containing many things, including pectin. Pectin breaks down into methanol; the kind of alcohol that kills and blinds people.
    If you want a good safe drink, make it yourself. If you want bad tasting drinks that contain methanol, buy alcohol from the store.

    Citrus juice is usually to cover the taste of strong drinks. If you're in a hurry for predrinking, you can mix booze with lemon juice in a 1:1 ratio and drink it like apple juice.

    For the acid reversing the reaction, would stomach acid be enough?
     
  5. May 28, 2005 #4

    GCT

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    safer, hmm really? I'm just not quite sure about that, also I would imagine that there would be some warning associated with the methanol issue from the FDA. From what I remember methanol is very potent.

    I'm quite sure that protonation would occur, either on the carbonyl oxygen or the alkyl oxygen, usually it is followed by elimination however it requires a nucleophile. Such protonation is somewhat typical of achieving symmetrical ketones, however I'm just not quite sure if the reversing would occur. You would also want to consider the stomach as a medium, and other considerations, the acid in the stomach might be more reactive towards other compounds, there's probably a biological simplification to all of this though.

    You know, something tells me that adding citric acid to alcohol should not affect its potency. It doesn't seem likely to me that one would be significantly more sober by adding lemon juice to an alcoholic beverage. Also, from what I remember the acid, alcohol esterification reaction occurs very slowly, acyl chlorides react faster. How did you check for the presence of esters in your home made drink?
     
  6. May 28, 2005 #5

    ShawnD

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    I'm really just assuming that it's easters. Mix liquid alcohol with liquid lemon juice and you end up with white flakes after a few minutes. I'll post back with some pictures when I can.

    edit
    Ok here is a picture of the supposed ester
    It's hard to see in a picture, but the chunks are settling to the bottom. I know it's not pulp because the lemon juice used in that mixture doesn't have any chunks in it.


    Also try not to reference the government when talking about anything. Have you ever seen Reefer Madness? That film pretty much destroyed any hope for listing the government as a credible source for anything.
     
    Last edited: May 28, 2005
  7. May 29, 2005 #6

    movies

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    What was your procedure to make the alcohol? It might not even involve the ethanol.
     
  8. May 29, 2005 #7

    ShawnD

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    Water + refined white sugar + yeast. Let it sit for a few weeks until it stops reacting.

    Ethanol and carbon dioxide should be the only major products of the reaction.
     
  9. May 29, 2005 #8
    Don't dilute acids (lemon juice) favor the acid+alcohol side of the equilibrium (with all that H20)? And hypothetically if you did have an ester, since citric acid molecules have 3 carboxylic acid groups (I think), and esterification is very slow, wouldn't most products be like mono-ethyl citrate, and still be very protic and very water-soluble (not precipitating as white flakes)? I'm suspecting you have something other than an ester.

    $0.02
     
  10. May 29, 2005 #9

    movies

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    Yeah, are you certain is not a bunch of dead yeast?
     
  11. May 29, 2005 #10

    ShawnD

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    Yeast does not evaporate.
     
  12. May 30, 2005 #11

    GCT

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    The only way to be sure, perform chemical tests or perhaps use your fractional distillation apparatus. And I suggest that whatever you do...don't drink the solution. Experiments such as these usually have specific parameters and careful measures in order to achieve the product in the end. Movies, do you know of any good online links for fisher esterification?
     
  13. May 30, 2005 #12

    movies

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    Wait, did you distill the product at all? What did you do to get rid of the yeast then?

    Fisher esterifications typically take a few hours of refluxing in a solvent like benzene, so this rate definitely seems unusual.
     
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