Potassium Metabisulphite - to prevent oxidation?

[BlackSands]

After reading this I started to wonder...

THE IMPACT OF AGE ON PLINY THE ELDER

Many homebrewers complain of 'hop-fade' but it seems commercial IPA's (well, this particular one anyway) suffer a lot less from this - certainly compared to my hoppier beers and this exbeeriment implies oxygen is to blame.  I was under the understanding though that with bottle conditioned beer the yeast actually scavenges up any oxygen that has found its way into the brew - e.g. from CC'ing and the bottling process itself,  but my current NZPA has already faded in just a matter of a few weeks. 

Having just made my first batch of wine where sulphite additions are a vital part of the process I then wondered why low doses of K-met aren't commonly used in brewing - particularly pre-packaging?  It seems a small dose of K-met can not only help scavenge up oxygen but also kill off bacteria and wild yeasts - a dose low enough that it doesn't effect the beer yeast itself which is still needed for bottle carbonation. 

Thoughts?  

Edited September 14, 2019 by BlackSands

[Otto Von Blotto]

I've always been sceptical of the idea that yeast scavenge all of the oxygen that might be in the beer or headspace after bottling, but temperature also plays a part in how quickly these things happen. 

It may be that there is no dose small enough to avoid killing the beer yeast that would actually have any benefit. I use the stuff in my brewing water to remove chloramine (and as a disinfectant in distilled water, just in case), but the sulphur dioxide gets boiled off well before any yeast goes near it. 

[ChristinaS1]

Brewers yeast are more sensitive to sulphites than wine yeasts, so I would be very hesitant to try it for bottle conditioned beers, unless you use EC-1118 champagne yeast for bottle conditioning. Might be worth an experiment.

Of course killing off the yeast would not be a concern to someone who kegs and force carbonates.

While the idea is intriguing, I suspect that there is a reason commercial breweries don't use K-meta. 

Cheers,

Christina.

Edited September 15, 2019 by ChristinaS1

[BlackSands]

6 hours ago, ChristinaS1 said:

Brewers yeast are more sensitive to sulphites than wine yeasts, so I would be very hesitant to try it for bottle conditioned beers, unless you use EC-1118 champagne yeast for bottle conditioning. Might be worth an experiment.

Of course killing off the yeast would not be a concern to someone who kegs and force carbonates.

While the idea is intriguing, I suspect that there is a reason commercial breweries don't use K-meta. 

 

I just read the following: 

Quote

KMS is by far the most popular antioxidant used in the brewing industry. Its popularity within some large breweries is because it is highly effective at preventing oxidation and because the added sulfites improve the naturally occurring sulfites produced by the yeast during fermentation. KMS is also active in limiting growth of wild yeasts and bacteria in beer...

...KMS is rarely used by craft brewers anywhere, but it is common in mass-market beers in many countries. In most countries the use of KMS is regulated by specific limits either to the total concentration of sulfites in beer or by maximum allowed dosing rates. The reason for these limitations is that sulfites are known to provoke and worsen certain allergies in humans. For example, in the United States, levels above 10 ppm will require the words “contains sulfites” to be printed on the label.

10ppm is roughly equivalent to one campden tablet in a 23litre batch, compared to the 5 tablets that are typically used to stabilise wine.  

After doing more online searching it would seem using KMS it not in fact unheard of in the homebrew community, and I've read accounts by IPA brewers that claim it has been a significant help to retaining hop freshness in their packaged beers.   Turns out Brulosophy has also done a exbeeriment.   While I guess these would be forced-carbed beers I've also read of some that add a campden tablet prior to bottling their beer, seemingly without concern of killing off the yeast.    

 

 

Edited September 16, 2019 by BlackSands

[ChristinaS1]

Ah, interesting. I did not know that. Thank you.

Are you going to give it a go? If so, I will be interested to hear how it goes. Maybe I will try it too. 

Cheers,

Christina.

Edited September 16, 2019 by ChristinaS1

[Otto Von Blotto]

The campden tablets I had would result in about 25-30ppm K met in a 23 litre volume, they were somewhere around 600-700mg in each one. I don't remember if it specified how much sulphites one would provide though.

[BlackSands]

10 hours ago, ChristinaS1 said:

Ah, interesting. I did not know that. Thank you.

Are you going to give it a go? If so, I will be interested to hear how it goes. Maybe I will try it too. 

Well... you know me!       I'll crush a tablet and add to the brew I'm about to bottle.  It's not a super hoppy beer but it's a light base with mellow hops which I know from my current PA almost fade away to nothing in a very short time.    I do have a slight concern that even if the beer yeast is not killed off it may still be a little compromised and given I already experience a very slow rate of carbonation after CC'ing I'm wondering if it will now take even longer?   

 

9 hours ago, Otto Von Blotto said:

The campden tablets I had would result in about 25-30ppm K met in a 23 litre volume, they were somewhere around 600-700mg in each one. I don't remember if it specified how much sulphites one would provide though.

I don't know how much k-met the tablets I have contain and maybe not all campden tablets are created equal?   I obtained the numbers I quoted from online sources.  Actually the usual dosage mentioned was 0.75 tablet/5gal.  BUT that was US gallons (19 litres) so I figured a whole tablet in 23 litres would be roughly equivalent.    

 

Watch this space!  

[James Lao]

Hey Blacksands,

Are the fading beers dry hopped only?

What hops are used in the fading beers?

I mainly use ‘big’  flavor hops like Citra and Mosaic and don’t tend to notice that hop  fade as an issue, but my beers never get older than 2 months.

Part of the attraction with homebrewing for me is that I know that what I am putting in is all natural, so I don’t get bad  hangovers etc

When I have a glass of wine or 2 the head is a lot worse the next day than 6 IPA homies, (350ml , 6.5% IPA is about the same alcohol as a glass of red) I have always thought this was because of the chemicals and additives they use when making wine?

Pardon my ignorance if K-met sulph is quite harmless, just thinking out loud.

Cheers

James

[ChristinaS1]

 

4 hours ago, BlackSands said:

Well... you know me!       I'll crush a tablet and add to the brew I'm about to bottle.  It's not a super hoppy beer but it's a light base with mellow hops which I know from my current PA almost fade away to nothing in a very short time.    I do have a slight concern that even if the beer yeast is not killed off it may still be a little compromised and given I already experience a very slow rate of carbonation after CC'ing I'm wondering if it will now take even longer?   

 

I don't know how much k-met the tablets I have contain and maybe not all campden tablets are created equal?   I obtained the numbers I quoted from online sources.  Actually the usual dosage mentioned was 0.75 tablet/5gal.  BUT that was US gallons (19 litres) so I figured a whole tablet in 23 litres would be roughly equivalent.    

 

Watch this space!  

Where are you getting that 0.75 tablet/5 US gallons dosage? That dose sounds low. Are you sure is wasn't per US gallon? Is that a dosage for wine? Or beer? 

Not sure if you rack to a bottling bucket to bulk prime BlackSands, but one article I read recommended dissolving the Campden tablet(s) in water first and then putting it into the bottom of the receiving vessel before racking, so it can be present as the oxygen is added.

This article says that prior to bottling wine, you want about 30mg/L of free SO2, which is equal to about 3 Campden tablets in 23L. 

https://winemakermag.com/wine-wizard/629-should-i-add-campden-tablets-each-time-i-rack-my-wine-and-how-do-i-measure-the-level-of-sulfite-in-my-wine

However, one thing I learned making country wines and cider is that how much sulphite you need depends on pH: the higher the pH, the more you need. The pH of beer is higher than that of wine, and the ABV is lower, which is another factor. Here is a sophisticated calculator:

https://winemakermag.com/resource/1301-sulfite-calculator

Using the recommendations for red wine (which are less than those for white wine) the calculator says that with a pH of 4.0 and 5% ABV, you would need 7 Campden tablets in 23L at 20C. That is actually a lot closer to what I usually see recommended: 1 Campden tablet per 4L or US gallon.

Given the uncertainty regarding dose, maybe I will wait and see how it goes for you BlackSands....It might be wise to start off with 1 Campden tablet per 23L, but I doubt that will do anything noticeable. You can always increase the dose by one tablet in subsequent batches, until you either notice it making a positive difference, or a bad smell, or hit seven tablets. With higher dosages, carbonation will likely be delayed. 

Cheers,

Christina.

Edited September 17, 2019 by ChristinaS1

[BlackSands]

14 minutes ago, James Lao said:

Hey Blacksands,

Are the fading beers dry hopped only?

What hops are used in the fading beers?

I mainly use ‘big’  flavor hops like Citra and Mosaic and don’t tend to notice that hop  fade as an issue, but my beers never get older than 2 months.

Part of the attraction with homebrewing for me is that I know that what I am putting in is all natural, so I don’t get bad  hangovers etc

When I have a glass of wine or 2 the head is a lot worse the next day than 6 IPA homies, (350ml , 6.5% IPA is about the same alcohol as a glass of red) I have always thought this was because of the chemicals and additives they use when making wine?

Pardon my ignorance if K-met sulph is quite harmless, just thinking out loud.

Cheers

James

The hop fade I regularly experience is in beers that are both dry hopped and late hopped.  But I think it's the dry hop that suffers mostly,  particularly the aroma.  And I'm talking just a few weeks.  It got to the point where I had decided at one time that dry-hopping was a waste of time because by the time the beer had had a decent amount of time conditioning the benefit of dry hopping was almost completely lost leaving me to think I' may well have not bothered.   As it happens I later changed my mind, as I now believed even a faded dry hopped beer still contributed a desirable character compared to a non-dry hopped brew. 

I read that the sulphites/headache thing is a myth and has actually been debunked, though I haven't actually looked for a direct source of this claim myself.   The dosages used in wine are considered to be well within safe limits, i.e. harmless and the dosage discussed here is 1/5 of that.  Also, it should be noted that sulphites are a natural by product of fermentation anyway.  

[James Lao]

Might be the 6 beers and then the 2 glasses of red that’s causing the headaches for me on a Saturday morning?

Seriously though, without really doing a lot of proper research into wine making, I have heard there are a lot of chemicals and additives on both red and white wine?

Regarding the hops, how much are you dry hopping per litre?

Cheers

James

[BlackSands]

2 hours ago, ChristinaS1 said:

 

Where are you getting that 0.75 tablet/5 US gallons dosage? That dose sounds low. Are you sure is wasn't per US gallon? Is that a dosage for wine? Or beer? 

Not sure if you rack to a bottling bucket to bulk prime BlackSands, but one article I read recommended dissolving the Campden tablet(s) in water first and then putting it into the bottom of the receiving vessel before racking, so it can be present as the oxygen is added.

This article says that prior to bottling wine, you want about 30mg/L of free SO2, which is equal to about 3 Campden tablets in 23L. 

https://winemakermag.com/wine-wizard/629-should-i-add-campden-tablets-each-time-i-rack-my-wine-and-how-do-i-measure-the-level-of-sulfite-in-my-wine

However, one thing I learned making country wines and cider is that how much sulphite you need depends on pH: the higher the pH, the more you need. The pH of beer is higher than that of wine, and the ABV is lower, which is another factor. Here is a sophisticated calculator:

https://winemakermag.com/resource/1301-sulfite-calculator

Using the recommendations for red wine (which are less than those for white wine) the calculator says that with a pH of 4.0 and 5% ABV, you would need 7 Campden tablets in 23L at 20C. That is actually a lot closer to what I usually see recommended: 1 Campden tablet per 4L or US gallon.

Given the uncertainty regarding dose, maybe I will wait and see how it goes for you BlackSands....It might be wise to start off with 1 Campden tablet per 23L, but I doubt that will do anything noticeable. You can always increase the dose by one tablet in subsequent batches, until you either notice it making a positive difference, or a bad smell, or hit seven tablets. With higher dosages, carbonation will likely be delayed. 

Cheers,

Christina.

@ChristinaS1 As mentioned earlier:

Quote

10ppm is roughly equivalent to one campden tablet in a 23litre batch, compared to the 5 tablets that are typically used to stabilise wine.  

Yeah, I've also read much on the topic and am aware of the above.   Roughly 1 campden/gallon for stabilising wine, but this is beer and we're not trying to stabilise.  Try searching for discussions relating specifically to the use of K-met with beer.  While most links will relate to de-chlorination if you keep digging you should find a good number of folks on various forums talking about dosing beer prior to packaging.    

Anyway, the brew has been bottled already.  One campden tablet dissolved in water,  and 150g bulk priming sugar also dissolved in water -  primed in the primary, both solutions gently stirred and given time to disperse.  Nottingham is such a great yeast for this... it compacts down so firm that I was even able to get the last dregs out with a minimal amount of yeast disturbance.  M36 is the same.  

Because I'm trying to build up stock (extra drinker in the house!) this is another brew that benefited from a mere 36 hours CC.  It was pretty clear going into bottles though at icy cold temps (actually - there was small amount of ice floating on top!   )   I have no doubt it will be a crystal clear beer when at served at fridge temps although I usually prefer my beer a little warmer.  It tasted REALLY nice too so I'm very much looking forward to drinking this in a few weeks.   I've placed one bottle in our hot water closet... it's about 25 - 26ºC in there so I should know pretty soon how the carbonation is doing.   In fact, it should be obvious one way or the other by tomorrow I reckon.   It will be weeks before I know if it's benefited in reducing hop fade though which of course is the main point of the exercise.  Anecdotal accounts suggest it does, but we'll see!

Edited September 17, 2019 by BlackSands

[BlackSands]

19 minutes ago, James Lao said:

Might be the 6 beers and then the 2 glasses of red that’s causing the headaches for me on a Saturday morning?

Beer + wine often give me headaches too. Not sure what it is about that combination?  

Quote

Seriously though, without really doing a lot of proper research into wine making, I have heard there are a lot of chemicals and additives on both red and white wine?

No, there's certainly not a lot of chemicals in wine.  Sulphites are added as discussed and in the case of white wine, potassium sorbate is also a common additive, not so much in red wines though.  While some home wine makers often use fining agents to clear the wine, so they can get it bottled as soon as possible, the commercial winemakers tend to bulk condition and allow time to do the clarifying job for them.  And that's about it as far as chemical additives in wine go as far as I know.

 

Quote

Regarding the hops, how much are you dry hopping per litre?

This particular brew is a fairly modest 2.2g/liter (50g) so not a huge dose,  but in the context of the light malt base it's certainly enough to be noticed, and enough to be noticed when it's all faded away!   With my APA's the dosage varies from 0g/liter to 4.3g/Litre (0g - 100g).  

 

Edited September 17, 2019 by BlackSands

[BlackSands]

This experiment doesn't address the issue of hop fade but rather focuses on (perceived) freshness:

POST-FERMENTATION OXIDATION: THE IMPACT ADDING SODIUM METABISULFITE AT PACKAGING HAS ON BEER
 

Quote

 

...participants in this xBmt were able to reliably distinguish a Kölsch packaged with SMB from one packaged without the preservative.

...the beer kegged without SMB had a distinct smell that was reminiscent of Golden Grahams cereal– biscuity and slightly sweet. This characteristic was completely absent in the beer kegged with SMB, which I perceived as having a cleaner Pilsner malt character. While both beers were good, my preference went to the one packaged with SMB.

 

 

 

 

Edited September 17, 2019 by BlackSands

[Norris!]

Could the hop fade be due to the fact that most commercial beers with noticeable hop presence seem to have larger rates of hopping per liter then 2.2g/l?  For example, a few years ago the stone and wood Pacific ale was very hoppy, to me, today it is nice but fairly tame when compared to an XPA or even a NEIPA.

If I want to notice the hops, I am adding more than 50g because I know if I let the beer sit for 2 months I will be drinking a lager, well a bland version of what I wanted.

If you want the hop aroma and flavour, drink early. If the beer is meant to age, then compensate with boiled additions and dry hopping and/or a recipe that favours the malt and yeast profiles versus the delicate hop aromatics. James noted the hops used, this could also be an issue. If you drink a brew bittered to the same level and dry hopped to the same level with azacca versus Hallertau you will get a clear idea about this. With the new beers that are highly hopped it could be a lot of things from pallete, recipe, hops used and rate of hops used and when. I think it comes down to the low rate and maybe the amount of late hops used in the boil.

Try a recipe with all bitterness coming from a flameout addition, or with just 25% from a 60 min addition with high AA hops and the hop fade will magically disappear.

Cheers

Norris

[Otto Von Blotto]

They probably do have higher rates of hopping but they also have the means to easily prevent oxygen from coming in contact with the beer every step of the way after the yeast is pitched, which home brewers generally don't unless you're fermenting in a keg and doing a closed transfer to a serving keg which has been completely purged of oxygen. Too much faffing around for me, although I wouldn't mind trying a closed transfer from the fermenter at some stage.

[ChristinaS1]

1+ what Kelsey said.

@BlackSands Thanks for the link to the Xbeeriment on using SMS in kegged lager. I guess he was looking more at its affect on malt flavour. It will be interesting to see what his results are when he gets around to using it in a NEIPA. But I guess we will get your results first! Bonus! 

In my experience hop fade is definitely a thing,  and this is backed up with research, with some hop compounds fading more quickly than others, and some being transformed into other flavour and aroma compounds. Here is quite a good article about it:

http://www.milkthefunk.com/wiki/Hops

The two most important aroma compounds (that we know about anyway) are geraniol and linalool. Timing of the dry hop and hop choice matter. Timing is more of an issue with geraniol....I read with interest that German and New Zealand hops are naturally low in geraniol, but American hops are high in it. BlackSands, I notice many of your recipes use New Zealand hops, which makes sense considering you live there. But maybe you should pair them with hops high in geraniol? And ones high in thiols too?....Centennial has a really high level of geraniol, and descent amount of linalool as well; it is one reason why I like to include some Centennial in my hop combos. 

I see that choice of yeast also play a role in bio-transformation of esters during fermentation, with lager strains showing the ability to do this whilst ale strains do not. That is another good reason to use the ale/lager blend that comes with the Mexican Cerversa and APA kits.   Not sure if it is true, since I have not used it in years, but I have read comments by some on home brew forums that Nottingham blunts hops. That is actually one reasons I have steered away from it.

Cheers,

Christina.

Edited September 17, 2019 by ChristinaS1

[James Lao]

I pretty much use Nottingham for every brew and haven’t noticed a blunting of hops, but that could be because I am used to it.

Combined with the fact that I am using American ‘heavy’ hops in my Brews ( 3-4g/L), that it is not noticed by me.

Maybe need to do a brew with US05, but am reluctant due to reports of clove flavors etc

Cheers

James

[BlackSands]

13 hours ago, Norris! said:

If I want to notice the hops, I am adding more than 50g because I know if I let the beer sit for 2 months I will be drinking a lager, well a bland version of what I wanted.

Sure, while this particular brew only has a 50g dry hop, on a light malt base that's still enough to produce a noticeable hoppiness at the glass and the point of the discussion really is to look at ways to preserve that for as long as possible.  I realise we can compensate for the loses but what I'm interested in really is minimising the loss and restricting exposure to oxygen seems to be what's required.  Regardless of the hopping rate I'm just curious to know whether k-met will help preserve whatever hop presence there is at time of packaging.

13 hours ago, Norris! said:

Try a recipe with all bitterness coming from a flameout addition, or with just 25% from a 60 min addition with high AA hops and the hop fade will magically disappear.

If this really were the case and it was that simple why is it that so many brewers of APA/IPA/DIPA and NEIPA are still lamenting about ongoing issues with hop-fade?   

10 hours ago, Otto Von Blotto said:

They probably do have higher rates of hopping but they also have the means to easily prevent oxygen from coming in contact with the beer every step of the way after the yeast is pitched, which home brewers generally don't unless you're fermenting in a keg and doing a closed transfer to a serving keg which has been completely purged of oxygen. Too much faffing around for me, although I wouldn't mind trying a closed transfer from the fermenter at some stage.

LODO     I note those that adopt low-oxygen brewing techniques include k-met as part of the process.

 

9 hours ago, ChristinaS1 said:

BlackSands, I notice many of your recipes use New Zealand hops, which makes sense considering you live there. But maybe you should pair them with hops high in geraniol? And ones high in thiols too?....Centennial has a really high level of geraniol, and descent amount of linalool as well; it is one reason why I like to include some Centennial in my hop combos. 

Yes, interesting point actually and now I think about it,  I don't use American hops very often I must admit. Amarillo most recently but as it's also THE most expensive hop here, almost twice the price of say Motueka,  it and other American hops are something of a rare treat.    Though this idea has merit it does seem that it too is  'compensating' for loss rather than 'minimising' it.  Anyway...  time will tell if k-met helps.  I will taste the beer as soon as it's carb'd and try get a REALLY good feel for the hops... then compare as the beer ages.  Not very scientific I know but I'm confident that it'll be obvious if hop-fade has occured. 

And...speaking of carbonation... the bottle that I put next to the hot water tank yesterday is well on the way.  The PET bottle is feeling quite firm already.     

Edited September 17, 2019 by BlackSands

[BlackSands]

Just now, James Lao said:

I pretty much use Nottingham for every brew and haven’t noticed a blunting of hops, but that could be because I am used to it.

Combined with the fact that I am using American ‘heavy’ hops in my Brews ( 3-4g/L), that it is not noticed by me.

Maybe need to do a brew with US05, but am reluctant due to reports of clove flavors etc

I think this unsubstantiated rumour that Notty subdues hops or that it tastes a bit tart is just malicious gossip perpetrated by US05 fanboys!  

I think with a bit of effort we could get a rumour going around the homebrew community about US05 being a bandaid/clove monster that should be avoided by all that value quality beer.  The only difference is some of us can actually substantiate the claim!   

[Otto Von Blotto]

Yes but LODO is mostly all pre fermentation, removing oxygen from the brewing water etc. rather than post fermentation treatment before packaging, at least that's how I understand it. 

I already use the stuff in my water anyway to remove chloramine from tap water and as an insurance policy in my distilled water, but I haven't noticed any difference in the retaining of hop aroma. 

[James Lao]

Thanks Google,

LODO =  LOw Dissolved Oxygen

 

Cant bloody stand TLA's and FLA's!!

Cheers

James

[ChristinaS1]

I actually know what LODO stands for, but I had to look up what TLAs and FLAs are. 

@BlackSands I read that some brewers are adding sodium metabisulphite when they add their dry hops, as that can add oxygen too. Maybe multiple additions of sulphite would be a good idea, as in wine making? But the total would add up....As far as I can tell, the 10ppm dose for adding at bottling is used not because different doses were tried and that was found to be the best, but because that is what commercial breweries can get away with without having to disclose it on the label.  Of course home brewers can do what they want.

Cheers,

Christina.

Edited September 17, 2019 by ChristinaS1

[ChristinaS1]

I have been thinking about ways in which I can reduce introducing oxygen to my beer on the cold side. I recently switched to kegging, from bottling. One nice thing about kegging is that I can transfer directly from the FV into the keg, without the need to first transfer into a bottling bucket (carboy) for bulk priming, which inevitably introduces a bit of oxygen. 

For those who bottle, bulk priming in the primary or using carbonation drops are two good ways to reduce oxygen ingress into your process....I have always been quite dismissive of bottle priming, but this is an important advantage of it that I did not appreciate before....I will actually be trying bottle priming in the near future, with beer that I don't keg. 

Cheers,

Christina.

Edited September 18, 2019 by ChristinaS1

[ChristinaS1]

@BlackSands  Do you use an auto siphon? I use an auto siphon, but the seal can leak air. I just saw a short Beersmith video where Brad said to pour a little sterile water into the outer tube so that if it leaks, it is sterile water and not air being mixed with your beer....I am going to try that. Think I might try applying a smidge of keg lube to my seal next time too.

Cheers,

Christina.

Edited September 18, 2019 by ChristinaS1