[Hajutze]

Now I am not really sure if this sub-forum is the correct one, but it looked like the best one to post in.

You know .. just in theory. Let's say that we have an orange juice gone bad (in other words - it's already fermented) so as far as I know - it contains alcohol right now. Is there a way to "remove" the alcohol with easy-to-get products ?

I am not really sure but the alcohol formed from fermantation should be acidic right ? So I need some sort of a base to "turn" the base and the acid into salt* and water.

*Not really sure if that's the correct term in english.

[Arkcon]

Now I am not really sure if this sub-forum is the correct one, but it looked like the best one to post in.

Not a problem, we can handle it after the fact

You know .. just in theory. Let's say that we have an orange juice gone bad (in other words - it's already fermented) so as far as I know - it contains alcohol right now.

Yes, industrial distillation will handle this problem.  Use of vacuum will prevent damage to the juice.

Is there a way to "remove" the alcohol with easy-to-get products ?

No, that's not possible

I am not really sure but the alcohol formed from fermantation should be acidic right ?
So I need some sort of a base to "turn" the base and the acid into salt* and water.

No. That is fundamentally wrong.

*Not really sure if that's the correct term in english.

Technically correct, just not applicable in this case.

[billnotgatez]

http://www.chow.com/food-news/53912/how-are-nonalcoholic-beer-and-wine-made/

I found this via GOOGLE

[vmelkon]

But even if you remove the alcohol, isn't it going to taste crappy?
Fermentation is done by yeast and these things have an enzyme (or 2?) that converts sucrose into glucose and then the glucose to ethanol and CO2 but the same enzyme also makes some aldehyde and ketone.

I know that they make something other than ethanol (maybe acetaldehyde for the aldehyde and acetone for the ketone) because I have fermented pure sucrose to make ethanol. I added some NaOH to the ethanol and after 1/2 a day, it produces a little bit of some oily yellow liquid which sits at the bottom. The oily liquid is generated by an aldol condensation.
I can then distill the ethanol again and thus, obtain a ethanol that is both acetaldehyde and acetone free.
==> so, you can get rid of the ethanol, acetaldehyde and acetone but perhaps there will be some other junk still in your juice.

[Ander08]

    Acetaldehyde is a common product of distilling alcohol. Ethanol and acetaldehyde both have a low boiling point so seperation by distillation would be difficult. But if you are simply extracting ethanol from a juice, there exists only trace amounts of acetaldehyde and acetone,. i do not believe it is enough to actually be harmful.

[vmelkon]

Yes, I guess you can get rid of it along with ethanol but I imagine the juice is going to still taste bad. Perhaps because of the yeast or perhaps the yeast produces some other chemicals. I remember drinking fermented orange juice 5 years ago. I think it tasted very acidic and had a weird taste. It made me want to spit it out fast.

[Ander08]

Well if there is no yeast in your juice, you arent producing alcohol, the juice is just decomposing. In order to ferment alcohol, you need a sugar and nutrient source (juice) and yeast. What you tasted was just rotten orange juice

[Ander08]

And also do not assume that if you react an acid with a base it will form a salt. A salt is an ionic compound, and if you introduce a base to a carboxylic acid, it simply will not form an ionic compound. HCL and NaOH will form an ionic compound NaCl. Say if NaOH and CH3C2OH, The result will not be a salt. The acidity in fermented orange juice is most likely the result of citric and acetic acid. Both are carboxylic acids

[408]

if you introduce a base to a carboxylic acid, it simply will not form an ionic compound

wrong

[Ander08]

408 i would appreciate if you followed up with a suggestion for a correct answer instead of just blatantly saying "wrong". If you produced an explanation of why I was wrong I would actually be learning something, which was the point of me joining this forum. To me it seems like you are just trying to make yourself look like you know better than me without supplying any proof that you actually know the real answer.

[Arkcon]

I can relate to you wanting more, but I don't see what there is to say.  An alkaline salt of a carboxylic acid is most definitely an ionic compound.  I can't see how you'd think it wasn't.  Example:  benzoic acid is a caboxylic acid, and because it contains a benzene ring, a pretty non-polar organic acid, not very soluble in water.  Reacted with sodium hydroxide, it forms the sodium salt, sodium benzoate, an ionic compound, that is very soluble in water.  Do you have a counter-example?

Not that any of this really addresses the O.P.

[Ander08]

Thank you for the clarity, and maybe I could have phrased my response better before. I did not mean it was impossible to create a salt with a carboxylic acid, i was simply saying that one cannot assume that introducing a base to an acidic solution would definitely yield a salt. I appreciate your response and since we are, in fact getting off topic I suppose we can end this argument here. Thank you again.

[vmelkon]

Thank you for the clarity, and maybe I could have phrased my response better before. I did not mean it was impossible to create a salt with a carboxylic acid, i was simply saying that one cannot assume that introducing a base to an acidic solution would definitely yield a salt. I appreciate your response and since we are, in fact getting off topic I suppose we can end this argument here. Thank you again.

When you said "NaOH and CH3C2OH" does not form an ionic compound, that didn't make much sense. I'm assuming you meant NaOH and acetic acid. This produces sodium acetate. It is a salt because it dissolves in water and ionizes 100% (Na+ ions are removed from the acetate). Go ahead and measure electrical conductance.

If you are using the Bronsted-Lowry definition, there are a bunch of organic compounds which have an amine group (NH2), an NH group or a N (with carbon neighbors) and these can behave as a base. N has a lone pair onto which a H+ can come and bind to. Even these can react with carboxylic acids and form a soluble salt.
Check out metoprolol succinate and metoprolol tartrate
http://en.wikipedia.org/wiki/Metoprolol

[Ander08]

Yes, I meant to say CH3COOH, and I understand that my explanation was wrong, I should have used a better example. Thank you for the response.

[curiouscat]

408 i would appreciate if you followed up with a suggestion for a correct answer instead of just blatantly saying "wrong". If you produced an explanation of why I was wrong I would actually be learning something, which was the point of me joining this forum. To me it seems like you are just trying to make yourself look like you know better than me without supplying any proof that you actually know the real answer.

I disagree. It is often very useful to know that one is wrong, even without knowing exactly how.