Purging headspace when bottling

[DuncB]

What about the suggestion by some that a dose of Sodium Metabisulphite will also absorb any oxygen, I'd like to find the hard facts about this rather than anecdotal it works!

 

[Silver_Is_Money]

Beware that roughly 1 in 100 people suffer allergic reactions to metabisulfite, up to and including anaphylaxis.

 

[Birrofilo]

Nope, I meant it the way I wrote it. I think an excessive dosage might be the reason.

I see. It's probably the scarce dosing that it is the reason as it appears that, below a certain unknown threshold, ascorbic acid can act as a "superoxidizer" - post #106 by @Silver_Is_Money - and the remedy is either to add a little bit of sulphides or increase the ascorbic acid dose substantially.

Adding sulphite has several cons:
- Beyond a certain threshold, it stinks;
- At any threshold, is not something good for you;
- Some people is allergic to sulphites - which is one of the reason why there is a compulsory mention in the label above 10 mg / litre - and I would like to avoid asking people, when I offer a glass of my beer, whether they have an allergy for sulphites.

Ascorbic acid was proven in this thread to be effective against oxidation if used in massive amount, 1 gram per US gallon or circa 5 grams for a 20 litres batch.

The cons of massive dose of ascorbic acid are:
- 5g on 10 litres is 20g for hectolitre and the law in Italy, or probably in the EU, for what I know, states a maximum of 15g / hl. Not clear to me whether this is the limit beyond which a mention in the label is compulsory, or an absolute limit. If the latter is true, it's an "illegal" beer. And imagine you offer it to somebody, who has an allergy to ascorbic acid (if that exists) and dies, you go behind bars.
- Not clear the effect on beer flavour for such massive amounts;

With my next bottling, I will use the 15g / hl maximum allowed, which I hope is sufficient to avoid the superoxidiser effect, and see how it works.

I tend to lay down beer for at least three months and I happen to drink beer which are 6 - 9 - even 12 months old.

 

[Birrofilo]

What about the suggestion by some that a dose of Sodium Metabisulphite will also absorb any oxygen, I'd like to find the hard facts about this rather than anecdotal it works!

Besides adverse reactions, in general sulphites are very nasty substances that wise people avoid. People rightly worry about "preservatives" and anything with an Exxx code, but in fact the two seriously toxic things are nitrites & nitrates, and sulphites. The rest is more or less not something I worry about from a health point of view (and I am pretty much paranoid about health).

Putting sulphites in the purest form of food that exists, beer, is blasphemy, it's a dirty trick to compensate poor brewing procedures. Say no to sulphites.

The LODO use of sulphite is different, because they use them in the kettle and they will be neutralized by the subsequent oxygenation. They will not be present in the final product, that practice might even pass the Reinheitsgebot "test". But adding them in the bottle, no thanks!

 

[DuncB]

So how come it is in so much wine if it is that dangerous?

 

[DuncB]

I see an incidence of sensitivity to sulphites when looking on Medline but not that high an allergic reaction.
Sulfites are ubiquitous in foods, cosmeticss etc.

 

[Birrofilo]

So how come it is in so much wine if it is that dangerous?

Wine naturally contains less than 10 mg / litre. Addition as a preservative is admitted in wine according to a set of rules which differentiates white, red, sweet wine. Up to 200 mg/l are allowed for white wine (40 times the natural occurrence, more or less), and more for sweet wine.

A medical theory, which I think is correct, says that the liver damage that drunkards undergo is due not to alcohol per se, but to sulphites.

The good news is that sulphites smell and can be detected by your nose. Very cheap stabilized wine is full of sulphite, up to the maximum extent allowed by the law. Quality wines normally don't smell sulphur, not a hint. When they do, change winery! A competent winemaker will not add more than 10 mg/litre and will additionally rinse the bottles in a sulphite solution (just like some homebrewer do) and drip them without rinsing them, and soak the corks in a sulphite solution. An incompetent winemaker will make you drink much more sulphur than necessary. Overall, the lack of sulphites is what makes beer (even) healthier than wine.

Small sulphite quantities will not give you a liver damage per se but they will compound with all the other toxic substances to which we inevitably expose our body (from food, from air, and even from underwear possibly, or jewels or watches). It's all tiny things that at the end sum up end make our liver life complicated or even miserable.

Quality wine, beer and distillates are good for your health. It's bad quality that makes bad health.

 

[DuncB]

@Birrofilo Thank you for that answer.
Not sure that the ethanoics liver issues are because of the sulphites so much. I don't expect there is any sulphites in methylated spirits.
Most likely it is actually the toxic effect of the ethanol and it's breakdown products by the P450 system, there may well be synergistic effects of poor diet, nutritional insufficiency and genetics all mixed in.

Still undecided whether a tiny quantity of Sod Met in the keg for very sensitive beers to oxygenation is worthwhile. Don't want to smell any sulphur in my pint.

 

[Birrofilo]

@Birrofilo Thank you for that answer.
Not sure that the ethanoics liver issues are because of the sulphites so much. I don't expect there is any sulphites in methylated spirits.

Quite correct. Drunkards in my country (I mean clochards who drink great amounts of alcohol each single day) don't buy distillates, they buy very cheap wine sold in tetrapak, because it's cheaper. And believe me, it stinks of sulphur markedly.

But if somebody gets drunk every day with gin, his liver will probably survive much, much better. Gin contains much fewer congeners than wine (and vodka, Campari etc.) Some royal family members of a certain state are a shocking demonstration of this basic truth, from hearsay