Ascorbic Acid and Beer

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An Ankoù

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Just come across a product called Ascorvit, which is basically ascorbic acid (vitamin C). It is claimed that it can be used as an antioxidant in beer. While I see there are plenty of references to ascorbic acid in wine and cider making, I can't find much on its use in brewing beer. Has anybody used it in beer? Does it work?
Thanks.
 
There appears to be research showing that it often works as intended, but apparently for some odd (and unknown?) reason it can also randomly have the opposite effect.
 
This is an interesting one. Although ascorbic acid is a reducing agent, under certain conditions (I think in the presence of copper for one) the redox reaction produces hydrogen peroxide which is actually a stronger oxidant than oxygen is.

But if ascorbic acid is used in conjunction with sodium metabisulphite (Campden tablets) then the sulphur dioxide released reacts with the H2O2 to produce sulphuric acid. So you'll get the antioxidant effect plus a small increase in sulphates (and H+).

There doesn't seem to be a lot of info on this though so it could be worth an experiment, a 3 way split batch, one with ascorbic acid, one with ascorbic acid and campden, and a control.
 
I detect it in a fair few 'craft' sours. The idea often being that it wasn't quite tangy enough prior to packaging. Especially in the ones labelled 'sherbet'.

Edit. Not the product you describe, but straight ascorbic acid.
 
I heard that used together with sulphite they work a lot better than on their own. No idea what ratios of each.
 
This is an interesting one. Although ascorbic acid is a reducing agent, under certain conditions (I think in the presence of copper for one) the redox reaction produces hydrogen peroxide which is actually a stronger oxidant than oxygen is.

But if ascorbic acid is used in conjunction with sodium metabisulphite (Campden tablets) then the sulphur dioxide released reacts with the H2O2 to produce sulphuric acid. So you'll get the antioxidant effect plus a small increase in sulphates (and H+).

There doesn't seem to be a lot of info on this though so it could be worth an experiment, a 3 way split batch, one with ascorbic acid, one with ascorbic acid and campden, and a control.
Indeed, this becomes more and more interesting. I shall have to look at how little SO2 I can get away with so I can still carbonate the bottled beer. Come to think of it, SO2 is a reducing agent itself and would act as an antioxidant so I wouldn't need the ascorbic acid if I could get enough in there and still carbonate. Hmm. And fruit wines and beers with fruit added with loads of natural Vit C don't seem to go off particularly quickly. I bit more reading and googling required on my part, I think.
 
I detect it in a fair few 'craft' sours. The idea often being that it wasn't quite tangy enough prior to packaging. Especially in the ones labelled 'sherbet'.

Edit. Not the product you describe, but straight ascorbic acid.
I thought it was pretty much straight ascorbic acid, in any case I was just going to grind down some vit C tablets and not bother about the lactose and other fillers. At least we know the dose of a single tablet.
 
Come to think of it, SO2 is a reducing agent itself and would act as an antioxidant so I wouldn't need the ascorbic acid if I could get enough in there and still carbonate
It is but it's not really a strong antioxidant. I have a feeling the amount you'd need would be pretty hard on the yeast which is why it's not really used for beer making (cold-side at least, I think the LODO guys use it hot-side because the SO2 is driven off during the boil).
 
I added 2g dissolved ascorbic to my current keg of Oktoberfest. Certainly no side effects noted so far and if the keg tastes as fresh when it's finished as it does now then I will use it again. I got my AA from cream supplies.
 
Have you read this? That's what put me onto the 10ppm thing I'm doing right now.
http://brulosophy.com/2019/02/11/po...at-packaging-has-on-beer-exbeeriment-results/
Thanks. No I hadn't seen it, but I've read it now. It's fine to sulphite your beer if you're going to force carbonate it in a keg, but if you want to bottle condition it, the presence of sulphur dioxide hampers the yeast. So we're back to square one. The "Real Ale in a Bottle" brigade must have found a way.
 
ut if you want to bottle condition it, the presence of sulphur dioxide hampers the yeast.
I'm bottle conditioning with sulphite right now, only a few days in - just cracked the cap on one bottle and it is carbed out the wazooo. 10ppm has done nothing to hamper this yeast.
 
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Thanks Steve, Drunkula, Foxbat et al.
This has been a very interesting discussion. I'm not aware that I've even got a issue with oxidation. My question was prompted by seeing Ascorvit on a homebrew suppliers website being plugged as an antioxidant in beer and I wondered if I was missing something. Maybe I am and I won't know until I've tried it. Indeed, I opened a very old bottle of very strong homebrew the other day and, although most of the citra character had disappeared, the beer was delicious- until the last mouthful when I detected a distinct "sherry" note. On the other hand, I've opened bottles of Duvel Tripple Hop- Citra (my wife's tipple of choice) over a year old and there's not all that much difference to a fresh one. Even the hops are still there!
So I'm going to set up an experiment along the lines Steve suggested above: a batch of strong, hoppy, blonde split three ways at bottling time: one with an appropriate amount of ascorbic acid as soon as I've determined what an appropriate amount is; one with 10ppm sulphur dioxide from sodium metabisuphite; and the last with no antioxidant- not even an oxygen scavenging cap.
I'll report back in about 3 months.
(Steve's comment about the present of copper: I use a coper wort chiller and while this puts insufficient copper in the wort to cause any toxicity to man or beast, there should be enough of a trace to catalyse the reaction he outlines above.)
 
@An Ankoù I had my first ever bottle bomb yesterday - It was one of the ones I'd sulphited, too. If you haven't looked it up 1g of metabusulphite powder is enough for 66 litres, one campden tablet is enough for 26 litres.
 
@An Ankoù I had my first ever bottle bomb yesterday - It was one of the ones I'd sulphited, too. If you haven't looked it up 1g of metabusulphite powder is enough for 66 litres, one campden tablet is enough for 26 litres.
No I hadn't looked it up, just clocked the 10 ppm. Nothing to bottle at the moment as it's too hot to brew. That's to say, it's too hot for me. Might get a saison on during the weeks.
 
Thanks Steve, Drunkula, Foxbat et al.
This has been a very interesting discussion. I'm not aware that I've even got a issue with oxidation. My question was prompted by seeing Ascorvit on a homebrew suppliers website being plugged as an antioxidant in beer and I wondered if I was missing something. Maybe I am and I won't know until I've tried it. Indeed, I opened a very old bottle of very strong homebrew the other day and, although most of the citra character had disappeared, the beer was delicious- until the last mouthful when I detected a distinct "sherry" note. On the other hand, I've opened bottles of Duvel Tripple Hop- Citra (my wife's tipple of choice) over a year old and there's not all that much difference to a fresh one. Even the hops are still there!
So I'm going to set up an experiment along the lines Steve suggested above: a batch of strong, hoppy, blonde split three ways at bottling time: one with an appropriate amount of ascorbic acid as soon as I've determined what an appropriate amount is; one with 10ppm sulphur dioxide from sodium metabisuphite; and the last with no antioxidant- not even an oxygen scavenging cap.
I'll report back in about 3 months.
(Steve's comment about the present of copper: I use a coper wort chiller and while this puts insufficient copper in the wort to cause any toxicity to man or beast, there should be enough of a trace to catalyse the reaction he outlines above.)
Did you ever do this experiment? I recently bought some ascorbic acid and was thinking of adding it with my dry hops until I read this thread.
 
Did you ever do this experiment? I recently bought some ascorbic acid and was thinking of adding it with my dry hops until I read this thread.
No. I didn't carry out the experiment I outlined above. Instead there was another thread to which @DocAnna contributed some input from various scholarly papers, which boiled down to adding 0.73 grams of vitamin C to the beer for every litre of headspace in the second fermenter after racking. She thought that would be quite sufficient and would leave a tad left over to deal with the headspace in the bottle- if bottling. So that's what I've done.
I don't know if it's made any difference because I wasn't away of a problem to start with.
 
Right. I was perhaps trying to be over cautious when buying it. I was concerned about oxygen contact when dry hopping, if fermentation had ceased. Even though I would always flush my fermenter with co2 afterwards, if that was the case. Are you aware of any negative effects of adding it during the dry hopping stage?
 
Right. I was perhaps trying to be over cautious when buying it. I was concerned about oxygen contact when dry hopping, if fermentation had ceased. Even though I would always flush my fermenter with co2 afterwards, if that was the case. Are you aware of any negative effects of adding it during the dry hopping stage?
None whatsoever. But, I rack my beer into secondary, add the Vit C and dry hop a couple of days later, when the beer starts to clear down.
 

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