Help! metabisulfite and Ascorbic Acid

Homebrew Talk - Beer, Wine, Mead, & Cider Brewing Discussion Forum

Help Support Homebrew Talk - Beer, Wine, Mead, & Cider Brewing Discussion Forum:

Ricochet67

Member
Joined
Feb 20, 2021
Messages
8
Reaction score
2
I have had oxidation problems in my previous beers, I decided to go for some LODO processes, but by mistake I added 0.6 grams of Potassium Metabisulfite and 0.6 grams of ascorbic acid to 18 Liters of strike water, for a final batch of 10.5 Liters (2.5 G), I want to know if this amount of chemicals is detrimental to human health and if I will have sulfur smells and tastes in the finished beer, the wort samples to check FG have a good taste and rich flavor never perceived before. I am very sorry for my bad English. Thank you
 
Last edited:

mac_1103

Supporting Member
HBT Supporter
Joined
Sep 15, 2022
Messages
964
Reaction score
1,450
Location
Virginia
The recommended daily amount of vitamin C is 90 milligrams for adult men and 75 milligrams for adult women. It's also a water soluble vitamin which makes it difficult to overdose. So 600 milligrams in 18 liters of beer isn't going to hurt anybody unless they drink about a dozen pints in one sitting. And at that point there's other stuff in the beer that will probably hurt them more.

I have no idea if that much ascorbic acid is good for your beer however, and I also have no idea about the K Meta.
 

eliastheodosis

Supporting Member
HBT Supporter
Joined
Dec 4, 2021
Messages
296
Reaction score
422
I have had oxidation problems in my previous beers, I decided to go for some LODO processes, but by mistake I added 0.6 grams of Potassium Metabisulfite and 0.6 grams of ascorbic acid to 18 Liters of strike water, for a final batch of 10.5 Liters (2.5 G), I want to know if this amount of chemicals is detrimental to human health and if I will have sulfur smells and tastes in the finished beer, the wort samples to check FG have a good taste and rich flavor never perceived before. I am very sorry for my bad English. Thank you
Hi there! Here is the BSG page for potassium metabisulfite. You can see they say that typical usage is 1-2 g/hL, which gives you 10-20ppm. They also say maximum usage generally shouldn't exceed 100ppm, so that would be 10 g/hL. You have 10.5 liters or .105 hL. So 10 g/hL for .105hL leaves you with a maximum recommended amount of 1.05 grams. I think you're okay there.


I see that @mac_1103 just explained the ascorbic acid better than I could so I will stop here and just say I agree with him.

I think you are good here in terms of safety. If it's tasty then drink it :mug:
 

Red over White

Well-Known Member
Joined
Feb 23, 2022
Messages
252
Reaction score
255
Location
Locust
You scrubbed 4-6 ppm o2 with the kmb depending on tablet or powder almost immediately and the ascorbic acid removed oxygen as well just an unknown amount or how long before before it had an effect. Neither one was harmful in the amounts used, no worries and no sulfur issues downstream.
 

dwhite60

Well-Known Member
Joined
Sep 13, 2009
Messages
1,142
Reaction score
739
Location
Wake County NC
Curious how the boiling process affected the efficacy of the metabisulphite and ascorbic acid. I'd expect some breakdown.

It seems adding these at kegging/bottling would make more sense.

When making wine adding sulphite at each racking is recommended so it does breakdown and outgas at room temperature.
 

Red over White

Well-Known Member
Joined
Feb 23, 2022
Messages
252
Reaction score
255
Location
Locust
Curious how the boiling process affected the efficacy of the metabisulphite and ascorbic acid. I'd expect some breakdown.

It seems adding these at kegging/bottling would make more sense.

When making wine adding sulphite at each racking is recommended so it does breakdown and outgas at room temperature.
With calculated additions of these made at Dough in, they should be expended before the boil. Metabisulfite has the ability to react quickly with oxygen to remove it, I can't speak for ascorbic acid I don't use it at all. I do believe though that it is much, much slower to remove oxygen than Metabisulfite.

I use heavy NaMeta in my kegs when I purge them, but only the very tiny amount left in the keg ends up in the beer. With closed loop xfers under pressure I feel I don't need extra NaMeta in the final package. Bottling however is a different story.
 

KegLand

KegLand.com.au - Delivering Top Innovative Gear!
HBT Supporter
Joined
Dec 20, 2022
Messages
111
Reaction score
77
Location
Australia
I have had oxidation problems in my previous beers, I decided to go for some LODO processes, but by mistake I added 0.6 grams of Potassium Metabisulfite and 0.6 grams of ascorbic acid to 18 Liters of strike water, for a final batch of 10.5 Liters (2.5 G), I want to know if this amount of chemicals is detrimental to human health and if I will have sulfur smells and tastes in the finished beer, the wort samples to check FG have a good taste and rich flavor never perceived before. I am very sorry for my bad English. Thank you

Can you please also tell us what equipment you are using and your process for storing beer. If you have a good process and good storage vessel oxidation should not be an issue so I tend to think some effort should be put into checking your hardware.
 

RPh_Guy

Bringing Sour Back
Joined
Jan 26, 2017
Messages
9,290
Reaction score
7,703
Location
Cleveland
You scrubbed 4-6 ppm o2 with the kmb depending on tablet or powder almost immediately and the ascorbic acid removed oxygen as well just an unknown amount or how long before before it had an effect. Neither one was harmful in the amounts used, no worries and no sulfur issues downstream.
Sulfites don't react immediate with O2, and neither does ascorbic acid (reactive oxygen species are another matter). Also he didn't say whether he deoxygenated the water or not, so there may not have been any oxygen in the strike water.

Curious how the boiling process affected the efficacy of the metabisulphite and ascorbic acid. I'd expect some breakdown.

It seems adding these at kegging/bottling would make more sense.

When making wine adding sulphite at each racking is recommended so it does breakdown and outgas at room temperature.
Boiling will have little effect on these compounds. Their degradation will be largely based on the amount of oxygen introduced during the brewing process.

With low oxygen brewing, antioxidants are used in the strike water during mashing in order the preserve fresh grain flavor, among other benefits. Adding antioxidants later won't recover the flavors lost during mashing to oxidation. Also, adding sulfites at packing can cause off-flavors in some cases.

Can you please also tell us what equipment you are using and your process for storing beer. If you have a good process and good storage vessel oxidation should not be an issue so I tend to think some effort should be put into checking your hardware.
Oxidation occurs throughout the brewing process. For example, the papery/cardboard flavor that may appear during beer storage is formed by lipid oxidation on brew day, most commonly during mashing.
 
OP
OP
R

Ricochet67

Member
Joined
Feb 20, 2021
Messages
8
Reaction score
2
Can you please also tell us what equipment you are using and your process for storing beer. If you have a good process and good storage vessel oxidation should not be an issue so I tend to think some effort should be put into checking your hardware.
I am a newbie, I use BIAB Method, Auto Siphon Racking, plastic fermenter, keep some trub in fermentation, No rack beer from primary to secondary fermenter, do diacetyl Rest or maturation and hot age, cold crash, priming sugar into beer bottle with a syringe, plastic filling tube, carbonation 10 days.
 

mac_1103

Supporting Member
HBT Supporter
Joined
Sep 15, 2022
Messages
964
Reaction score
1,450
Location
Virginia
Their degradation will be largely based on the amount of oxygen introduced during the brewing process.
Right. Degradation isn't even rally the right term. Antioxidants do their job by getting oxidized before the things you don't want to get oxidized. They aren't degrading, they're getting used up.
 
OP
OP
R

Ricochet67

Member
Joined
Feb 20, 2021
Messages
8
Reaction score
2
Los sulfitos no reaccionan inmediatamente con el O2, y tampoco lo hace el ácido ascórbico (las especies reactivas de oxígeno son otra cuestión). Tampoco dijo si desoxigenó el agua o no, por lo que es posible que no haya oxígeno en el agua de la huelga.


La ebullición tendrá poco efecto sobre estos compuestos. Su degradación se basará en gran medida en la cantidad de oxígeno introducido durante el proceso de elaboración.

Con la elaboración de cerveza con poco oxígeno, los antioxidantes se utilizan en el agua de huelga durante la maceración para conservar el sabor del grano fresco, entre otros beneficios. Agregar antioxidantes más tarde no recuperará los sabores perdidos durante la maceración a la oxidación. Además, agregar sulfitos en el empaque puede causar malos sabores en algunos casos.


La oxidación se produce durante todo el proceso de elaboración de la cerveza. Por ejemplo, el sabor a papel/cartón que puede aparecer durante el almacenamiento de la cerveza se forma por la oxidación de lípidos el día de la preparación, más comúnmente durante el macerado.
 
OP
OP
R

Ricochet67

Member
Joined
Feb 20, 2021
Messages
8
Reaction score
2
Sulfites don't react immediate with O2, and neither does ascorbic acid (reactive oxygen species are another matter). Also he didn't say whether he deoxygenated the water or not, so there may not have been any oxygen in the strike water.


Boiling will have little effect on these compounds. Their degradation will be largely based on the amount of oxygen introduced during the brewing process.

With low oxygen brewing, antioxidants are used in the strike water during mashing in order the preserve fresh grain flavor, among other benefits. Adding antioxidants later won't recover the flavors lost during mashing to oxidation. Also, adding sulfites at packing can cause off-flavors in some cases.


Oxidation occurs throughout the brewing process. For example, the papery/cardboard flavor that may appear during beer storage is formed by lipid oxidation on brew day, most commonly during mashing.
Yes, I deoxygenated 22 liters with active dry yeast for 1 hour before adding potassium metabisulfite, A.A + CaCl2 for HEFEW and used 18 liters as strike water and removed 4 liters for grains, then added back in wash. I don't know if it's the best method to make 2.5 gal in a small pot, I always use full volume.
 

RPh_Guy

Bringing Sour Back
Joined
Jan 26, 2017
Messages
9,290
Reaction score
7,703
Location
Cleveland
Yes, I deoxygenated 22 liters with active dry yeast for 1 hour before adding potassium metabisulfite, A.A + CaCl2 for HEFEW and used 18 liters as strike water and removed 4 liters for grains, then added back in wash. I don't know if it's the best method to make 2.5 gal in a small pot, I always use full volume.
¡Muy bien! Full volume is much easier to keep low oxygen, instead of sparging.
 
Top