Reusing Star San

[IslandLizard]

I read that it is not the ph thats degrades, its the dodecylbenzenesulfonic acid

That's the inkling I had too, the surfactant breaking down with time. I noticed the foaming character changes with time, say after 14-30 days the foam is not as thick anymore. No exact data on that.

Makes one wonder how it fares at the super high concentrations in the stock bottle... Haven't noticed any issues when using those, even being 7 years old, some were even older.

 

[bwible]

Here's a current discussion of "How Old Is Your Star San?"

How Old Is Your Star San?


I can't provide facts, but just going by my experience, a 5 gallon made batch lasts me a few brew sessions. A spray bottle usually a few months. As long as your ph is around 3, you should be good. I used to keep my batch in a 6 gallon bucket. Now, I use a spare keg for storage. That way I can sanitize a cleaned empty keg and transfer lines before kegging.

I've been brewing for 11 years and I'm on my second bottle of Star San. The first bottle was a 32oz bottle that got years of use. I got down to 4 oz left before buying a 16oz bottle. The first bottle starting getting a weird smell to it, so I chucked it.

I started the “how old is your Star San” thread and the question at the time was not regarding mixed Star San but rather your bottle of unmixed Star San. I had a very old bottle of unmixed Star San, (16 years old?) I was having some contamination issues at the time and I was wondering if my really old bottle of unmixed Star San was no longer effective. I later got some ph test strips and proved it was still good.

 

[bwible]

I’ve been using the same 5gal bucket of star san mix since March. I’m about halfway through it (lose some every batch). It still foams as if brand new and I’ve not had even a hint of an issue.

That and I also read if its clear. Some seem to believe if its cloudy then its no longer effective.

I also re-use mixed Star San when its reasonable. I keep a carboy full and I syphon the Star San from one carboy to another to sanitize my auto syphon and tubing, for example.

 

[balrog]

Some seem to believe if its cloudy then its no longer effective

I believe that if you have high carbonate water it will be cloudy the instant you make some up; so that the cloudy metric is not necessarily foolproof, while pH is much better indicator of effectiveness.

 

[mac_1103]

I don't really see how it could be ineffective if the pH is below 3 and it still foams, but I always make up a little bit fresh on brew days for the FV.

 

[Yesfan]

I started the “how old is your Star San” thread and the question at the time was not regarding mixed Star San but rather your bottle of unmixed Star San. I had a very old bottle of unmixed Star San, (16 years old?) I was having some contamination issues at the time and I was wondering if my really old bottle of unmixed Star San was no longer effective. I later got some ph test strips and proved it was still good.

But the link I provided to your thread is relevant, is it not? How else would a bottle of Star-San last 16 years if one isn't reusing made up batches?

 

[IslandLizard]

I don't really see how it could be ineffective if the pH is below 3 and it still foams, but I always make up a little bit fresh on brew days for the FV.

It's not just the Phosphoric Acid (pH) that makes Starsan work, it's the acid in combination with a soap-like detergent/cleaner, dodecylbenzenesulfonic acid in Starsan's case.

The pH could still be well under 3 (2.5-2.7 from what I've measured), but it's rendered mostly ineffective by itself when the soapy substance, that accompanies it, has degraded beyond a certain threshold for it to do its work.
@Jeroen had mentioned this, above, in #27:

I read that it is not the ph thats degrades, its the dodecylbenzenesulfonic acid, and that is there to break down the cell walls of the bacteria, it that is gone the acid won't be that effective.

 

[mac_1103]

It's not just the Phosphoric Acid (pH) that makes Starsan work, it's the acid in combination with a soap-like detergent/cleaner, dodecylbenzenesulfonic acid in Starsan's case.

That's why I said "and it still foams." The acid doesn't make Starsan foamy. The surfactant does,

 

[IslandLizard]

That's why I said "and it still foams." The acid doesn't make Starsan foamy. The surfactant does,

I know you said that.
We can measure the acid's activity level (pH), but we can't measure the soap's activity that easily. IOW, there's no easy way to determine how much the surfactant has degraded over time, which can hamper Starsan's overall effectiveness as a sanitizer. Longer submersion/contact time may help getting adequate sanitation, overcoming a potentially less active soap function, as the product degrades over time.

I have reported a noticeable change in a Starsan working solution's foaming character over time, when mopping Starsan onto a surface. Over time the foam becomes less thick in its coverage, sticking less to the surface.

With time (several days to weeks) a Starsan working solution becomes more watery and less foamy, so to speak.

 

[user 246304]

Just a current data point.

Hello, I'm hoping you can clear up some confusion. I only recently happened to notice you recommend using a prepared Star San solution immediately, and discarding within an hour. You used to recommend going by a pH benchmark - so long as the pH remained below a certain threshold, the solution is still viable. In this way, in a sealed (gamma-lidded) container, I was able to use the solution for quite some time.
I use RO water to prepare the solution. Can you please advise as to why the information has changed?"

Here's directly from Five Points:

Hi Paul

Thanks for reaching out about our products. If your solution of Star San is at a PH of 3.5 or below and you are using RO water the sanitizer is still good to use. I apologize about the confusion but these are the guidelines from the EPA for a sanitizer to actually sanitize. I would recommend storing the solution in a sealed container or 32oz spray bottles. Please let me know if you have any questions.

Which is what I suspected. There inclusion of "EPA" in the description led me to believe it was a regulatory thing, not a true reflection of the product's sanitizing ability over time.

 

[IslandLizard]

Just a current data point.

Thank you for reaching out and relaying the information you received.

I apologize about the confusion but these are the guidelines from the EPA for a sanitizer to actually sanitize.

The EPA must be using pretty tight guidelines!

Now we know what it takes, maybe we can start making truly good beer, instead of that infected swill we got so used to.

 

[mac_1103]

The EPA must be using pretty tight guidelines!

My guess is that the rule is for use in a commercial setting, but I also guess that I'm mildly surprised that it's EPA rather than FDA.

 

[IslandLizard]

I'm mildly surprised that it's EPA rather than FDA.

Yeah, same here.

 

[fluketamer]

im still using my 3 month old cloudy spray bottle with cat hair ,ants and the odd hop leaf . im convinced thats what adds the flavor.

 

[mschoeffler]

i cycle with each batch but get the most out of it.

7.5 gallons fresh in fermenter
—>
Plate chiller
—>
Keg
—>
Purged to bucket
—>
Empty mash tun
—>
Rinse clean fermenter
—>
Driveway

 

[ncbrewer]

There inclusion of "EPA" in the description led me to believe it was a regulatory thing, not a true reflection of the product's sanitizing ability over time.

When Charlie Talley was the Five Star president, he was on many podcasts and discussed how Star San can actually be used, compared to EPA regulations. After he moved on, they seemed to revert to strict EPA regulations. Judging from the reply you got from them, I guess they are starting to go back to real world capability of the product. I'm glad to see it.

 

[IslandLizard]

I guess they are starting to go back to real world capability of the product.

But with a "pot life" of merely 1 hour it's not very useful in the real world of brewing.

I was not aware that the EPA (Environmental Protection Agency) would be even remotely involved in testing sanitation products and writing guidelines for sanitation practices around food and beverages, being well outside of their typical realm of waste products and effluents and their impact on the environment.

As @mac_1103 mentioned we would expect that domain of sanitary regulations and guidelines for food and beverage products and handling to lie with the FDA (Food and Drug Administration).

 

[Dog House Brew]

I mix it with distilled in a 5g jug. I use it all year. I’ve never had any PH reading out of wack. An hour, that covers them for every water mixing hardness. The harder your water, the shorter the life. Mix it with distilled and no worries.

 

[day_trippr]

EPA has some purview over surface sanitizers and disinfecting agents. If it was meant to be applied on a human, nope, but on surfaces, yup.
Generally I appreciate that the EPA exists and generally have no issues with their machinations, but I think this looks hinky. Given I've been using Star San for almost 20 years, routinely maintain a ~6 gallon reservoir of standard mix for months for all of the sanitation needs around my humble brew space including occasional keg purging (hence the reservoir volume) and have yet to experience an evident infection.

fwiw, wrt Star San "life time", I came across this:

"Direct quote from Charlie Talley:

[Star San has three active ingredients: phosphoric acid, DDBSA, and propylene glycol] The acid-ionic [detergent or surfactant] is a synergistic killing machine. The acid by itself will not kill bacteria. The anionic detergent by itself will not kill bacteria. The combination of the two, at the correct ratio, is an absolute stone killer ... [The EPA requires you to make a fresh batch of sanitizer for every use ...] The material is kind of interesting. Like I mentioned before it is a, uh, it is a soap. It’s an acid anionic detergent. Um, if it’s made with deionized water, if the used solution is made with deionized water and there are no minerals in the water itself, um, the used solution is active for literally months. Uh, if there’s minerals in the water, what will happen over a period of time, the minerals will win out over time and they’ll start to create a hard water soap. The hard water soap will make the product cloudy. Only because, just like people use bar soap and they get soap tub rings. It works identically. There’s no difference in the chemical reactions behind it. And any brewer that uses the product and is in a hard water situation, I always tell ‘em to go to the supermarket and buy a jug of deionized water off the shelf. Um, they’ll thank me for it later on — and they do. They call me back up and they say, “Boy the water, you know, the sanitizing solution is crystal clear. Some of ‘em even have pH meters, um, some home brewers. And, uh, they go, “My pH it, uh, remains at 3, um, for two or three months.” I say, “Yeah, you’re still sanitizing. You’re still killing ... You can test the effectiveness in two ways, by the pH, or by the, uh, turbidity of the actual used solution. How cloudy it is.”

Cheers!

 

[G_robertus]

EPA has some purview over surface sanitizers and disinfecting agents. If it was meant to be applied on a human, nope, but on surfaces, yup.
Generally I appreciate that the EPA exists and generally have no issues with their machinations, but I think this looks hinky. Given I've been using Star San for almost 20 years, routinely maintain a ~6 gallon reservoir of standard mix for months for all of the sanitation needs around my humble brew space including occasional keg purging (hence the reservoir volume) and have yet to experience an evident infection.

fwiw, wrt Star San "life time", I came across this:

"Direct quote from Charlie Talley:


Cheers!

I'm not sure I understand the part on hard water soap and cloudiness. Does that imply the surfactant properties decline with time and/or minerals present?
FWIW I've tested tap water Star San after months and the pH was fine. The product was also still foaming, although it might've declined somewhat. I've yet to experience issues with old solution though. I usually throw it out when enough of the surfactant precipitates and I get a thin soapy film on the bucket, but that can be months. Or when stuff gets in there.

 

[day_trippr]

Or when stuff gets in there.

Yeah, material loading is what gets me to mix up a fresh batch. I use a 6.5g virgin bucket and if I see some debris on the bottom that'll do it
I use my RO system water and it stays bell clear and the pH will sit right where it was from the day it was mixed...

Cheers!

 

[G_robertus]

Mine gets cloudy incredibly fast, but like I said, it seems to remain functional a long time. I'll dive a bit deeper into the exact mechanics when I have some spare time.

 

[balrog]

I generally use it until it smells (typically hoppy) or gets to that degree of un-foamy that I subjectively and personally define as "not foamy enough, makes me feel utzy". And no, I do not have a device that can quantitatively measure that, or bluetooth IOT the results to a spreadsheet.

Yet.

 

[MaxStout]

And no, I do not have a device that can quantitatively measure that, or bluetooth IOT the results to a spreadsheet.

Yet.

Don't worry, someone will come up with one.

"Look for the Tilt Sanitizer Suds Defender with WiFi, available soon! Pre-orders taken now, $99, plus shipping."

 

[cubalz]

I just learned that Five Star recommends throwing the solution out after an hour. At that rate, one brew day would cost several dollars.

Yeah, that is just ridiculous

 

[FloppyKnockers]

I just learned that Five Star recommends throwing the solution out after an hour. At that rate, one brew day would cost several dollars.

I don't take any chances with sanitation. I throw it out as soon as I mix it up. Sanitation is key people!

 

[Ninoid]

I have a 10L plastic canister into which I pour 5L of demineralized water and 10mL of Starsan concentrate every few months and close it tightly. The bottle of Starsan concentrate of 118 mL has lasted me several years and I have not noticed any problem with disinfection. I only use the spray bottle and Viator, so I don't need a large amount (less than half a liter per double batch, and most of it is for disinfecting the bottles with Viator). But I don't reuse the used solution.
There is probably a durability problem if the disinfectant has been exposed to air for more than an hour or if tap water is used.

 

[ncbrewer]

I don't take any chances with sanitation. I throw it out as soon as I mix it up. Sanitation is key people!

I'm not such a fanatic. If my brew day is six hours, I make up six batches of Star San - one per hour. Be reasonable.

 

[FloppyKnockers]

I hope you check the pH every five minutes to ensure viability.