Peracetic (peroxyacetic) acid

[FatDragon]

A fellow China homebrewer recommended Peracetic acid as a sanitizer. I've got some freshly mixed up right now and I'm going to be bottling a batch in an hour or so. The problem is that this stuff smells strongly of acetic acid (even at 0.2% dilution, which from my reading seems to be a standard low-end dilution for sanitization). Can I sanitize my bottles with this stuff before bottling, or should I be using iodophor like I usually do?

Also, at this concentration, do I need to worry about getting this stuff on my skin, or is 0.2% dilution weak enough that it won't act as an irritant?

 

[The_Bishop]

I'm not familiar with peracetic acid, but I'd stick to common sanitizers. I'd be concerned about the 'vinegar' aroma hanging around in the finished beer.

According to wikipedia, the PEL (permissible exposure limit) for this stuff is low, which means it could have exposure and health concerns. The residue left behind could cause issues.

I'd avoid it.

 

[mabrungard]

Peracetic acid (PAA) is a very useful and safe sanitizer when used at low concentrations. Only about 100 ppm PAA is sufficient to kill virtually all microorganisms.

The presence of acetic acid aroma is not a surprise. It turns out that PAA exists in equilibrium with its two main constituents: acetic acid and hydrogen peroxide. The acetic acid is not a problem in brewing and if PAA is used as a spray or is drained from the equipment, there won't be a flavor impact to the beer.

While the PEL is low, the warning signs of exposure are unmistakable and should be sufficient to get the user to avoid excessive and adverse exposure. If your eyes water or your nose or mouth mucous membranes are irritated, then you need to get away from that area. Spraying the solution in a ventilated area should keep most users out of a hazardous situation.

PAA is widely used in many food and beverage industries including brewing and should be used more by homebrewers.

 

[FatDragon]

I'm not familiar with peracetic acid, but I'd stick to common sanitizers. I'd be concerned about the 'vinegar' aroma hanging around in the finished beer.

According to wikipedia, the PEL (permissible exposure limit) for this stuff is low, which means it could have exposure and health concerns. The residue left behind could cause issues.

I'd avoid it.

It was pitched as a cheap alternative to StarSan, which is hard to get and crazy-expensive here - almost $50 for a 32 oz container if you're lucky enough to find a place that's not perennially sold-out - smaller volumes are significantly more expensive price-volume, as bad as $12/4oz. Peracetic acid, on the other hand, is under $3 for a liter (33.8 oz). The guy who suggested I use it is out for the month, though, so I'll probably just leave it on my shelf until he gets back and can give me a better tutorial.

 

[The_Bishop]

Star San can be used far more economically than most on here do. I'll usually mix up a gallon at brew time, and that's plenty. You don't need to fill the fermenter with it, enough to slosh around and wet everything is enough.

I mix mine using RO water, so it has a good shelf life. I keep a 32 oz spray bottle filled for spot sanitizing, and I'll top it off then I mix up a batch for brewing.

 

[Stealthcruiser]

Star San can be used far more economically than most on here do. I'll usually mix up a gallon at brew time, and that's plenty. You don't need to fill the fermenter with it, enough to slosh around and wet everything is enough.

I mix mine using RO water, so it has a good shelf life. I keep a 32 oz spray bottle filled for spot sanitizing, and I'll top it off then I mix up a batch for brewing.

Check his location.........

 

[The_Bishop]

I get that. He said starsan was available, just expensive. I'd rather spend a buck or two more on a known safe sanitiser and use it conservatively, rather than an unknown that could ruin the beer or make the drinker sick.

 

[FatDragon]

Peracetic acid (PAA) is a very useful and safe sanitizer when used at low concentrations. Only about 100 ppm PAA is sufficient to kill virtually all microorganisms.

The presence of acetic acid aroma is not a surprise. It turns out that PAA exists in equilibrium with its two main constituents: acetic acid and hydrogen peroxide. The acetic acid is not a problem in brewing and if PAA is used as a spray or is drained from the equipment, there won't be a flavor impact to the beer.

While the PEL is low, the warning signs of exposure are unmistakable and should be sufficient to get the user to avoid excessive and adverse exposure. If your eyes water or your nose or mouth mucous membranes are irritated, then you need to get away from that area. Spraying the solution in a ventilated area should keep most users out of a hazardous situation.

PAA is widely used in many food and beverage industries including brewing and should be used more by homebrewers.

Wish I had seen this sooner - this is the kind of informed answer I was hoping for, but I was writing a response while it was posted so I didn't notice it until today.

I was aware that Peracetic was basically H2O2 and Acetic Acid, so I wasn't surprised when I smelled the strong vinegar smell, but I was also deadly afraid that using this stuff in the vinator or rinsing a bucket with it would make a beer taste just a bit too much like kombucha for my liking. I'll probably still use iodophor for my vinator until I run out, but this response makes me feel more comfortable about using this Peracetic in my home brewery. Less than $3 wouldn't have been a great loss if it turned out I couldn't safely use this stuff, but I'm glad that's not an issue.

 

[The_Bishop]

Somehow, I completely missed MBrungard's reply in following up to this thread.

I now find myself more informed. Doh.

 

[Contrarian]

Its what I use. Never noticed any negative effects.

 

[FatDragon]

Its what I use. Never noticed any negative effects.

When I saw there was a reply from username "Contrarian", I was definitely hoping for a hilarious "well, actually" response. Color me disappointed. :fro: Or whatever you call that color, I guess.

 

[Queequeg]

Peracetic acid is what commercial breweries use. I used to use it at work, even at low concentrations is smells bad. It is very effective disinfectant though, its efficacy its very good.

Another consideration if you don't like the smell is chlorine dioxide, again used in commerical breweries, its efficacy is even better than PPA

A third option is hypochlorous acid, but I am not sure about its no rinse potential.

 

[Queequeg]

PAA is widely used in many food and beverage industries including brewing and should be used more by homebrewers.

If it weren't for the smell I would, unfortunately I can't stand it. A lot of pubs use it in the UK and as soon as i walk in if they have been using it I can smell it. Really irritating in all senses of the word.

One thing that always concerns me with Star San is its not fungicidal or sporicidal. When weighing out grain lactobacillus spores are always in the back of my mind.

 

[Brad2287]

If it weren't for the smell I would, unfortunately I can't stand it. A lot of pubs use it in the UK and as soon as i walk in if they have been using it I can smell it. Really irritating in all senses of the word.

One thing that always concerns me with Star San is its not fungicidal or sporicidal. When weighing out grain lactobacillus spores are always in the back of my mind.

Lactobacilus is not a spore former so no worries there. I use PAA fairly regularly as I get it free from work. The smell is hideous when concentrated and bad when diluted. The efficacy is excellant and have experience using it in the formulation of high level disinfectants and chemical sterilants.

 

[Queequeg]

I had to look that up, I simply assumed because they were bacilli they were spore forming. Anyhow I still worry about all the brown card that homebrew stuff gets delivered in. That stuff is full of bacillus

Yeah the smell of the concentrate is beyond description. The procedure is lid off, dispense, close as quickly as possible.

I can get sometimes sterile H2O2 from work which I used to sanitise my fermenter between batches.

 

[shorestyle]

I work in a commercial brewery and we use peracetic acid in 0.2% dilution for sanitizing almost everything in the brewery except yeast brinks (which we use boiling water for). It's great and we've never had an infection. In 0.2% concentration the only dangers I've found from it is it dries out your skin pretty badly if you don't wear gloves while handling it.