FoodBanter.com

FoodBanter.com (https://www.foodbanter.com/)
-   Winemaking (https://www.foodbanter.com/winemaking/)
-   -   Ascorbic acid sources (https://www.foodbanter.com/winemaking/76112-ascorbic-acid-sources.html)

[email protected] 08-12-2005 10:00 PM

Ascorbic acid sources
 
I couldn't google this info..Has anyone ever used "Fruit Fresh" as
their source of ascorbic acid and oxidation reduction/prevention?

Thanks,
Jim L.


Droopy 08-12-2005 10:19 PM

Ascorbic acid sources
 
That should work. I beleive it has sugar in it so do not add it prior
to bottling with stabilizing it first.


Jon Gilliam 08-12-2005 10:35 PM

Ascorbic acid sources
 
Ascorbic acid (vitamin C) really only protects against oxidation for a very
short time. You might want to add a small amount just before racking in
conjunction with meta bisulfite, or if you're aerating wine to remove a
hydrogen sulfide smell, but generally ascorbic acid isn't a good way to
protect against oxidation. Since ascorbic acid works not by protecting from
oxidation itself but by increasing the efficiency of other antioxidants
(like meta bisulfite), in cases where you don't have enough bisulfite in the
wine, ascorbic acid may actually increase the rate of the wine's oxidation.

A cheap and easily available source for ascorbic acid is vitamin C tablets,
which you can crush in a spoon. I'd stay away from the fresh fruit unless
(such as lemons) unless they're a primary ingredient for the wine you want
to make (and I particuarly won't introduce them into a vinifera-grape wine).

Jon
[Check out my winemaking homepage
http://users.rcn.com/jcgilliam/Southeast_PA_Winemaker/!]

> wrote in message
oups.com...
>I couldn't google this info..Has anyone ever used "Fruit Fresh" as
> their source of ascorbic acid and oxidation reduction/prevention?
>
> Thanks,
> Jim L.
>




[email protected] 09-12-2005 12:37 AM

Ascorbic acid sources
 

wrote:
> I couldn't google this info..Has anyone ever used "Fruit Fresh" as
> their source of ascorbic acid and oxidation reduction/prevention?
>
> Thanks,
> Jim L.


I have added Fruit Fresh to my must before I ferment. Can't find it
anymore. Now I use crystaline Vit C from Trader Joe's -- got a big
botlle of that, should last me a long time. Most people prefer to add
acid in the form of acid mix. The acidity of Vitamin C seems to fade
during fermentation, I'm guessing the yeast are eating it, which is why
I like to use it early in the fermentation. If you search the web,
you'll find some references to using ascorbic acid to prevent oxidation.


billb 15-12-2005 06:29 AM

Ascorbic acid sources
 
Now I use crystaline Vit C from Trader Joe's -- got a big
> botlle of that, should last me a long time


how much do you add per gallon?

--
billb
I don't care who you are fat man, get those reindeer off my roof.
Life is a series of small disasters leading up to that one big diaster.
Deport illegals to China, that's where the jobs are anyway.
Yes, I know what you mean, but I've already spoken to Ferrari. You'll still
win at roulette.
Ted Nugent called, he want's his shirt back.
> wrote in message
oups.com...
>
> wrote:
> > I couldn't google this info..Has anyone ever used "Fruit Fresh" as
> > their source of ascorbic acid and oxidation reduction/prevention?
> >
> > Thanks,
> > Jim L.

>
> I have added Fruit Fresh to my must before I ferment. Can't find it
> anymore. . Most people prefer to add
> acid in the form of acid mix. The acidity of Vitamin C seems to fade
> during fermentation, I'm guessing the yeast are eating it, which is why
> I like to use it early in the fermentation. If you search the web,
> you'll find some references to using ascorbic acid to prevent oxidation.
>




Tom S 15-12-2005 03:54 PM

Ascorbic acid sources
 
"billb" > wrote in message
.. .
> Now I use crystaline Vit C from Trader Joe's -- got a big
>> botlle of that, should last me a long time

>
> how much do you add per gallon?


I don't understand why you wish to add ascorbic acid to a healthy wine. My
understanding is that it _promotes_ oxidation, rather than prevents it.

The only reason I know of for adding ascorbic acid to wine is if you have a
dimercaptan problem (rubber boot smell). It breaks the dimercaptan into
monomercaptan, and that can be treated with copper sulfate, usually followed
by activated charcoal.

Tom S
www.chateauburbank.com



Sam Wigand 15-12-2005 06:43 PM

Ascorbic acid sources
 
Tom S wrote:

>
>
> I don't understand why you wish to add ascorbic acid to a healthy wine. My
> understanding is that it _promotes_ oxidation, rather than prevents it.
>


>

I was sure that ascorbic acid was an anti-oxidant. No?

Droopy 15-12-2005 07:12 PM

Ascorbic acid sources
 
no, ascorbic is a reducing agent. It can function a lot like
metabisulfite, but it is weaker.

I guess people might want to use it if they are sulfite sensitive.


Sam Wigand 15-12-2005 07:38 PM

Ascorbic acid sources
 
Droopy wrote:
> no, ascorbic is a reducing agent. It can function a lot like
> metabisulfite, but it is weaker.
>
> I guess people might want to use it if they are sulfite sensitive.
>


Nevertheless, see the Wikipaedia entry for Vitamin C, where it is
described as an anti-oxidant.
http://en.wikipedia.org/wiki/Vitamin_C

pp 15-12-2005 07:56 PM

Ascorbic acid sources
 

Sam Wigand wrote:
> Droopy wrote:
> > no, ascorbic is a reducing agent. It can function a lot like
> > metabisulfite, but it is weaker.
> >
> > I guess people might want to use it if they are sulfite sensitive.
> >

>
> Nevertheless, see the Wikipaedia entry for Vitamin C, where it is
> described as an anti-oxidant.
> http://en.wikipedia.org/wiki/Vitamin_C


>From what I remember, it is an antioxidant for a short time, but then

some reaction happens and it actually promotes oxidation as Tom said.
Because of that it should never be used instead of sulfite. The use
I've heard is adding some while bottling (and maybe racking) and
reducing the amount of sulfite used at the same time. It sounded like
too much hassle with doubtful gain, but it might make sense for people
who are sensitive to suliftes.

Pp


Droopy 15-12-2005 08:13 PM

Ascorbic acid sources
 
I was not saying "no" to you sam, but to Tom.

Reduction is the opposite of oxidation.

Being an anti-oxidant is often the thing as being a reducing agent.
Oxidation is when an atom loses electrons (and its oxidation number
increases. So if you take iron and let it rust it goes like this 2 Fe
+ O2 -> 2 FeO the iron lost two of its electrons and has oxidized to
the Fe2+ state. Now if you heat that rust with hydrogen gas H2 you can
REDUCE the oxidation number of the iron back to 0 and you get the iron
metal back and water FeO + H2 -> Fe + H2O. That is reduction.

Ok, now the difference between being an anti-oxidant and being a
reducing agent. An anti-oxidant is a special class of reducing agents
that can accept electrons from free radicals and reactive oxygen
species. Those chemicals do not chemically react with things in such a
nice chela manner as above with the rust. Instead they tent to give
things extra electrons that they do not need and damage them. But they
do not exactally chemically combine with those things. So
anti-oxidants are reducing agents, but reducing agents may not be
anti-oxidants.

The reason I use reduction instead of anti-oxidant is becasue that
oxidation in wine is not always due to free radicals or reactive oxygen
species. Instead it is more like the "rust" example. That is oxygen
(and other stuff) is chemically reacting with wine components and
changing their character. The wine is "rusting"

I dunno, it is a subtle difference. To a chemist like me it is a big
difference.....but to all of you it is probabally a forgettable one.


JEP62 16-12-2005 03:43 PM

Ascorbic acid sources
 

Droopy wrote:

Snipped...

May well be a reducing agent, but numerous experiments using ascorbic
acid in white wines have shown that it actually promotes the browning
effect in whote wines. The ascorbic acid oxidizes and forms
dehyrdroascorbc acid and hydrogen peroxide. We definetly don't want
hydrogen peroxide in our wine.

It was also shown to increase the consumption of sulfur dioxide in the
wine so if ascorbic acid is used, you need to increase the amount of
SO2, not decrease it.

The conclusions I usually see are that while ascorbic acid can have a
short term benefit in preventing oxidation, once the ascorbic acid is
oxidized, is causes more harm than good. Using just SO2 is a better
method of protecting your wine unless you need the ascorbic acid for
other reasons (like a dimercaptan problem).

Andy


billb 17-12-2005 09:10 AM

Ascorbic acid sources
 
So if you take iron and let it rust it goes like this 2 Fe
> + O2 -> 2 FeO the iron lost two of its electrons and has oxidized to
> the Fe2+ state. Now if you heat that rust with hydrogen gas H2 you can
> REDUCE the oxidation number of the iron back to 0 and you get the iron
> metal back and water FeO + H2 -> Fe + H2O. That is reduction.
>

Well now I understand it.

I had that back in chemistry and i think when i was told that oxidation
takes electrons away and reduction didn't, that made no sense so I made no
effort to understand it.

Been one of my lifelong problems, if it doesn't make sense on the surface, I
skip it.

So, if I get some hydrogen gas I can turn a rusty old pinball part back into
its former self?? This I wanna see.

--
billb
I don't care who you are fat man, get those reindeer off my roof.
Life is a series of small disasters leading up to that one big diaster.
Deport illegals to China, that's where the jobs are anyway.
Yes, I know what you mean, but I've already spoken to Ferrari. You'll still
win at roulette.
Ted Nugent called, he want's his shirt back.
"



billb 17-12-2005 09:21 AM

Ascorbic acid sources
 
Those chemicals do not chemically react with things in such a
> nice chela manner as above with the rust.


so is chelation therapy any good?

--
billb
I don't care who you are fat man, get those reindeer off my roof.
Life is a series of small disasters leading up to that one big diaster.
Deport illegals to China, that's where the jobs are anyway.
Yes, I know what you mean, but I've already spoken to Ferrari. You'll still
win at roulette.
Ted Nugent called, he want's his shirt back.
"Droopy" > wrote in message
oups.com...
> I was not saying "no" to you sam, but to Tom.
>
> Reduction is the opposite of oxidation.
>
> Being an anti-oxidant is often the thing as being a reducing agent.
> Oxidation is when an atom loses electrons (and its oxidation number
> increases. So if you take iron and let it rust it goes like this 2 Fe
> + O2 -> 2 FeO the iron lost two of its electrons and has oxidized to
> the Fe2+ state. Now if you heat that rust with hydrogen gas H2 you can
> REDUCE the oxidation number of the iron back to 0 and you get the iron
> metal back and water FeO + H2 -> Fe + H2O. That is reduction.
>
> Ok, now the difference between being an anti-oxidant and being a
> reducing agent. An anti-oxidant is a special class of reducing agents
> that can accept electrons from free radicals and reactive oxygen
> species. Instead they tent to give
> things extra electrons that they do not need and damage them. But they
> do not exactally chemically combine with those things. So
> anti-oxidants are reducing agents, but reducing agents may not be
> anti-oxidants.
>
> The reason I use reduction instead of anti-oxidant is becasue that
> oxidation in wine is not always due to free radicals or reactive oxygen
> species. Instead it is more like the "rust" example. That is oxygen
> (and other stuff) is chemically reacting with wine components and
> changing their character. The wine is "rusting"
>
> I dunno, it is a subtle difference. To a chemist like me it is a big
> difference.....but to all of you it is probabally a forgettable one.
>




gene 17-12-2005 12:12 PM

Ascorbic acid sources
 
billb wrote:

> So if you take iron and let it rust it goes like this 2 Fe
>
>>+ O2 -> 2 FeO the iron lost two of its electrons and has oxidized to
>>the Fe2+ state. Now if you heat that rust with hydrogen gas H2 you can
>>REDUCE the oxidation number of the iron back to 0 and you get the iron
>>metal back and water FeO + H2 -> Fe + H2O. That is reduction.
>>

>
> Well now I understand it.
>
> I had that back in chemistry and i think when i was told that oxidation
> takes electrons away and reduction didn't, that made no sense so I made no
> effort to understand it.
>
> Been one of my lifelong problems, if it doesn't make sense on the surface, I
> skip it.
>
> So, if I get some hydrogen gas I can turn a rusty old pinball part back into
> its former self?? This I wanna see.
>


The rust would go back to being iron, though the surface will never be
as smooth as before.

With wine it's not so simple... the heat would change the flavor big
time; nevva be anything like its former self.


All times are GMT +1. The time now is 04:38 PM.

Powered by vBulletin® Copyright ©2000 - 2024, Jelsoft Enterprises Ltd.
FoodBanter