Moldy Fermetor -Super Bleach, Super KMeta

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Mar 3, 2010
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Well there was a splash of mold in my fermentor and I am making my first wine kit so I didn't want there to be any trouble. I decided against using boiling Hydrochloric acid to sterilize and went for the next best thing... Bleach.

Someone here in another thread had a link to a brewtalkradio podcast with the maker of Sterisan? talking about using bleach to sterilize (not clean, and to leave it rinse free afterward.) I just doubled/tripled all the doses and rinsed well afterward.

The trick was to add vinger to the bleach solution to lower the pH and produce more of the lethal agent.......whose name I forget.

1oz bleach (30ml), 5 gal water, 1 oz vinger (30ml).

I am sure it must have been a killer solution because it went GREEN. Die mold, die.

Next I rinsed well, and soaked and rinsed to get rid of any bleach aftertaste.

Then I used KMeta. And I had heard that adding Citric Acid to this, (again to lower the pH) made it more effective. And boy did it ever. I had the fermentor sealed up for an hour and when I took the lid off the wall of Sulphurous vapour that came out just about took my head off, cough, cough, cough.

Otherwise it was just my standard dose for sanatizing of 1 teaspoon Sodium Metabisulphate to one litre of cool water (this time with the addition of a teaspoon of citric acid.)

After that I made the wine kit up. Will see how it goes.
Im sure you did a go job but that dosage of k-meta is incorrect, its supposed to be 3 table spoons to 1 gallon of water + additional 3 table spoons of citric acid also.
The podcast you reference was by the inventor of Star San ... in the podcast, he mentions that in a perfect world, a bleach solution is a good sanitizer ... but the problem, he goes on to say, is that not all bleach is created equal ... and that some bleach formations don't sanitize at all. He also said that folks can cause more problems by not using bleach correctly ... so he set out to develop a "perfect" sanitizer ... which is Star San.

We've been using Star San for quite a while ... with excellent results. Not only to sanitize carboys and equipment, but tabletops, chairs and occasionally, the floor. (Ok, so we're messing sometimes!)

We use it in combination with k-meta mixed to sanitizing strength also.

I don't have the link to the star san podcast. I'm sure someone will post it here.
Wow Wade, that sounds like a killer solution of KMeta. Really that much?? To sterilize after cleaning? Sheesh, I have made plenty of beer & sterilized with one teaspoon to a litre (that would be just under a tablespoon to a Gallon) and that was before I started adding the citric acid and no problems so far. This is making a solution that I slosh everything in and leave in a sealed fermentor for an hour or so, assuming that the gas is doing its work, and then I just empty it out, no rinsing, and pour in whatever wort or wash I am making.
Yor actually really not that closeto bein a true sanitizer. There are 3 teaspoons in every table soon and it takes 3 tbls spoons per gallon or approx 4 liters in a gallon so basically you should be using 2.25 teaspoons per liter.
I see they talk about that in the Winemakermag article (I can't provide the link to the other thread in 'sanitation') but they also recommend a good rinse after-wards. Probably no rinse is not a problem for wine, but for my beer-making I might start noticing a sulphity taste at that level???

I will defer to your advice anyway and up the level for my wine-making.

Now on a similar vein, being cheap, and not wanting to waste my valuable NaMeta here is another question, its the gas doing the work right? (in a sealed container at least). So I don't need to put very much of that solution into an otherwise cleaned container.... Will a quarter of a gallon do for my 30 litre container? I can't use the smell test because it just leaves me coughing.
Rinsing could possible recontaminate so its not really advised. You are right about the gases and it doesnt take much at all of the solution to do its thing. I make up a gallon of the solution but dont add the citric acid, I only add the citric acid to the very small amount of solution that Im using at the time to make it work faster and better. Adding citric acid to your whole solution will make it stronger but also make it loose its potency faster because its releasing its S02 much faster when opened. You should use Starsan for making beer its a much better product for beer and what you dont rinse out actually is used as a nutrient for your beer.
Here's the LINK to the podcast. To be honest, despite the fact that both bleach and vinegar are evil to wine, combined I believe the speaker and inventor of Star San is right. WARNING IT CAN KILL YOU IF YOU DO IT WRONG.

The interview part that deals with this starts around 8:55 into the entire podcast.

I've been using this inexpensive method faithfully for our last half a dozen kits or more. For everything from sanitizing primaries to equipment and bottles.

So far, no issue....I'll let you know if it all goes to hell.

And no, my wine room does not sell like a pool room.

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k-meta for wine
starsan for beer
thats my methodology.

i really dont like bleach and esp do not like bleach mixed with vinegar, the slight added benefit of lowering the ph of bleach versus the cost of toxic chlorine gas poisoning is not worth it to me. bleach+vinegar, bleach+ammonia is highly toxic. if you throw caution to the wind and do it, do it outside or in VERY well ventilated area. but i do not recommend it at all. esp when there are so many inexpensive and safe alternatives.