Star San vs Iodophor PH

[TheCookieMonster]

Hi,

Star San needs to be under a 3.5 PH to be effective although it will still kill up to 4 from what I here. Just not as effective. What makes Star San 'no rinse' is that you are going to dilute it with a HIGHER ph wort. This will 'de-activate' the Star San. I think a lot of people do not understand what makes star san 'no rinse'. If the concentration is too strong, it is no longer 'no rinse' and it will kill your yeast. A brew lore myth got created that Star San will kill everything but your yeast. Like somehow it's magic and will kill the foreign yeast and not your WP001. Have a bunch of star san foam sit in your little 1L starter and add your 5.2ph wort to it and see what it does to your yeast if you get it down to 3.5ph. Am I off base here?

I'm trying to figure out Iodophor, but there's just sooo much food industry info on that it's too much to sift through so I'm hoping someone here knows the answer.

Does Iodophor act like Star San in it's PH? What makes it no-rinse or 'de-activates' the killing action of Iodophor?

Also, my 'Homebrewing for Dummies' book calls sodium metabisulphite 'no rinse'. I was told that for beer you can't use it.. Any info on that would be great appreciated.

Thanks!

 

[TipsyDragon]

StarSan is active below 3PH. although i have not personally done this i have heard of people accidentally forgetting to empty their carboys of StarSan and pouring their wort in. the beer fermented fine. granted the resulting solution was higher than 3PH once the beer was added. thats what people are referring to when they say StarSan will not kill your yeast.

Iodophor is just iodine.

Sodium Metabisulfite will kill the yeast at the proper concentrations (1 tablet per gallon). you need the yeast to condition and carbonate your beer.

 

[Hound]

Re Star San - if it only works at 3.5 pH or lower, does one have to get the pH of the water that you mix it into down to 3.5pH or lower for it to work? thi is not mentioned on the Star San container.

 

[kurtism]

Re Star San - if it only works at 3.5 pH or lower, does one have to get the pH of the water that you mix it into down to 3.5pH or lower for it to work? thi is not mentioned on the Star San container.

when you dilute the star san properly, the resulting pH is fine. making your water acidic then adding star san is not advisable. what would you use to drop the pH anyway?

 

[Hound]

I have nitric acid for another item I produce which needs pH to be lowered at times.

so I take it from your answer that all I need do is add the Star San to regular tap water and it will bring the pH down anyway?

 

[erikpete18]

so I take it from your answer that all I need do is add the Star San to regular tap water and it will bring the pH down anyway?

Regular tap water will work just fine for the initial use, but do yourself a favor and pick up some deionized water and mix it with that. The minerals in regular tap water will eventually precipitate out the phosphate in the star san and cause the pH to rise back up. If you make it with deionized water, it should remain at the lower pH for as long as it takes to use it all up. I like to make 1 gal batches in the deionized water jugs, or make up several gallon batches and store it in a corny and just keep using it until its gone. You can do a quick check with a pH strip to make sure that its still at the appropriate point if its been a while since its been used.

 

[Hound]

Thank you both for your informative replies.

I mixed a bucket of Star San yesterday as an experiment. As per the instructions I put one oz of StarSan into 19lts (thats 5 US gallons) and it stayed foggy, it did not clear. I then added 4 litres which brought the total volum of tap water up to 23lts (which is 5 UK gallons). It's still foggy this morning!!

I've read in Palmer that it should be clear and that if it is not that it is not an effective sanitizer. Might my bottle of StarSan be gone off? There's no best by date on it.

Any light that you may be able to shine on this would be appreciated very much.

 

[day_trippr]

I'd say there's a significant mineral load in your tap water.

If I mix Star San with my well water it will become cloudy within a half hour. So I took to mixing up a five gallon batch using distilled water. Three months and many brew days later it's still clear with a pH below 3.

fwiw, I didn't have the pH meter back when I used Star San with my well water so I'd have to experiment to see if cloudy = too high pH for reliable sanitation...

Cheers!

 

[Hound]

I'd say there's a significant mineral load in your tap water.

If I mix Star San with my well water it will become cloudy within a half hour. So I took to mixing up a five gallon batch using distilled water. Three months and many brew days later it's still clear with a pH below 3.

fwiw, I didn't have the pH meter back when I used Star San with my well water so I'd have to experiment to see if cloudy = too high pH for reliable sanitation...

Cheers!

Correct, I have very hard water...I brew/attempt to brew stout. Good suggestion, I'll buy some distilled water today and see if it works later.

 

[erikpete18]

Although with the cloudiness, it doesn't necessarily mean that it won't work anymore. Really the only way to tell is to pH it. I've heard of people with the same problem (mixing it up and immediately clouding) testing it and its still below the pH. If you've got access to some pH strips that should answer it. But yeah, distilled is really the way to go, and provides some peace of mind.

 

[audger]

my starsan mix is usually cloudy when i use tap water. according to pH strips it is still active, and it lasts for 1+ months this way. ive never had it sit around for longer so i have never tested that.

the ONLY test to determine if a starsan soloution is still effective is a pH test. cloudy-ness is not an indication one way or the other.

 

[Hound]

I bought bottled water yesterday and checked the pH - it was 7.1. When StarSan was added at the correct dosage, it sayed clear. So at least I know my StarSan is still ok, it brought the pH down to 2.7

I then tested the 5 gallons to which I had added StarSan two days ago, it gavea pH of 3.2. It's still extremely cloudy, but from what I read here this morning it should be ok. Palmer, whom I have great faith in, says that if it's cloudy it's not good for sanitizing. However I'm inclinded to go with the two previous post on this thread, ie that if the pH is below 3.5 it works, cloudy or not. If anyone has any evidence to the contrary it would be good to have it posted here.