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Thank you guys!
@Queequeg it would be really greate contribution to the community if you could validate the test of Inquisitor Home Brewing discussed in the other thread about StarSan efficiency. My personall perception is that StarSan does not do what it says it does. In addition, their follow up test shows that minimal inhibitory concentration of StarSan is around 6%. Given the number of people using it, I believe you would do a huge favor to everyone.
One of the key things missing in that test to which you linked is the actual populations of organisms introduced into the solutions of disinfectants. That alone makes it impossible to validate the results to a tee. You'd be better off inoculating hard surfaces (PE or stainless steel coupons, as those are relevant materials) and testing a matrix of exposure conditions and exposure times.

If you're interested in the exact tests that Star-San would have had to under go to be labeled as a food-safe sanitizer on hard surfaces, they are listed here: https://www.homebrewtalk.com/forum/threads/sanitizing-products-exist.648816/#post-8277404
 
One of the key things missing in that test to which you linked is the actual populations of organisms introduced into the solutions of disinfectants. That alone makes it impossible to validate the results to a tee. You'd be better off inoculating hard surfaces (PE or stainless steel coupons, as those are relevant materials) and testing a matrix of exposure conditions and exposure times.

If you're interested in the exact tests that Star-San would have had to under go to be labeled as a food-safe sanitizer on hard surfaces, they are listed here: https://www.homebrewtalk.com/forum/threads/sanitizing-products-exist.648816/#post-8277404

But here we are entering into a sort of gray area. Nowhere on its labels it says sanitatizer, thereore legally it might have never been a sanitizer.

https://www.jstrack.org/brewing/msds/starsan.pdf again no single word "sanitizer". It is reffered as sanitizer by the community but may technically not be it.

Don't get me wrong, I am not telling you or anyone how to do the test, I am in no way a professional. But my user level observation is that changing from StarSan to 3% H2O2 made a huge difference. So I do trust to people mentioned in that other thread, but it would be great if someone could actually prove with empirical not anecdotal evidence if StarSan actually works. Because my perception is that it does not.

It seems to me it should not be a big deal for a professional to test wether or not something else is growing from the sample of beer brewed on equipment sanitized with StarSan.

And I think someone has mentioned the population here Is Starsan good desinfectant? (spolier: no). Which was reffered as "a lot", but that could be adjusted to the proper values faced in typical brewing environments (i.e. kitchen or garage).
 
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But here we are entering into a sort of gray area. Nowhere on it's label it says sanitatizerm thereore legally it might have never been a sanitizer.

https://www.jstrack.org/brewing/msds/starsan.pdf again no single word "sanitizer". It is reffered as sanitizer by the community but may technically not be it....


It seems to me it should not be a big deal for a professional to test wether or not something else is growing from the sample of beer brewed on equipment sanitized with StarSan.

You are looking at the wrong label. You linked to the safety data sheet (SDS), which only provides information related to safety of the chemicals in the solution. You need to look at the EPA-mandated label that is required for legally-marketed, EPA-registered sanitizers. The label is present on the bottle of Star San, but you can also find it on EPA's website using the registration number: 65001-1 (https://www3.epa.gov/pesticides/chem_search/ppls/065001-00001-20171219.pdf). Note that the federal definition of "label" includes all product information like brochures, websites, and instructions for use.

Again, Star San is registered as a sanitizer with the EPA. To do so, it had to be registered under the federal insecticide, fungicide, rodenticide act (FIFRA). I have been through the FIFRA process on the pharma/med-dev sterilization side of things, and the EPA only accepts hard evidence, not anecdotal. But, that also comes with the understanding that the testing is done under very controlled circumstances that do not represent every real-world situation.

As to how easy it is for professionals to test this; it may actually be quite difficult from a logistics and policy standpoint. Most professional microbiology labs, especially those that are used in regulated industries, don't exactly smile upon unsanctioned testing done after hours.
 
You are looking at the wrong label. You linked to the safety data sheet (SDS), which only provides information related to safety of the chemicals in the solution. You need to look at the EPA-mandated label that is required for legally-marketed, EPA-registered sanitizers. The label is present on the bottle of Star San, but you can also find it on EPA's website using the registration number: 65001-1 (https://www3.epa.gov/pesticides/chem_search/ppls/065001-00001-20171219.pdf). Note that the federal definition of "label" includes all product information like brochures, websites, and instructions for use.

Again, Star San is registered as a sanitizer with the EPA. To do so, it had to be registered under the federal insecticide, fungicide, rodenticide act (FIFRA). I have been through the FIFRA process on the pharma/med-dev sterilization side of things, and the EPA only accepts hard evidence, not anecdotal. But, that also comes with the understanding that the testing is done under very controlled circumstances that do not represent every real-world situation.

As to how easy it is for professionals to test this; it may actually be quite difficult from a logistics and policy standpoint. Most professional microbiology labs, especially those that are used in regulated industries, don't exactly smile upon unsanctioned testing done after hours.
Thank you once again for giving your time and efforts to this discussion. I apologize for being so annoying, but the letter of the label registration states the following "On pre-cleaned food contact surfaces STAR SAN ACID SANITIZER is effective against Escherichia coli (ATCC 43888) and Staphylococcus aureus (ATCC 6538)." Someone, please, correct me if I am wrong, but viability of those two beasts referenced in the label and on the list of tests is incomparable to bacillus subtilits or clostridium botulinum in both vegetative and spore forms. The first one generates higher spirits and the second botulinum toxin. Either can be easily found in the soil and dust, but neither you want in your beer, do you?
 
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Thank you once again for giving your time and efforts to this discussion. I apologize for being so annoying, but the letter of the label registration states the following "On pre-cleaned food contact surfaces STAR SAN ACID SANITIZER is effective against Escherichia coli (ATCC 43888) and Staphylococcus aureus (ATCC 6538)." Someone, please, correct me if I am wrong, but viability of those two beasts referenced in the label and on the list of tests is incomparable to bacillus subtilits or clostridium botulinum in both vegetative and spore forms. The first one generates higher spirits and the second botulinum toxin. Either can be easily found in the soil and dust, but neither you want in your beer, do you?
Not annoying at all, I think it's a good discussion.

E. coli
and S. aureus are the standard organisms that are used to challenge a sanitizer for food-contact applications during the FIFRA registration process.

Sanitizers are not required to demonstrate efficacy against spore-forming organisms. That would fall under a sporicidal claim, which has another set of requirements where the test organisms are B. subtilis and C. sporogenes (Clostridium strain that does not result in toxins, but serves as a surrogate for C. botulinum). The sanitizer claims are limited to food-borne pathogens. It is a matter of using organisms that are representative of what one would normally encounter in the application. I don't think one often encounters C. botulinum in their brewing (or food preparation) areas when other sanitary (cleaning) practices are regularly applied. The relatively low pH of beer is not favorable for growth of either of those organisms.

If you're interested, I tracked down a PDF of the method that would have been used for Star San (AOAC Method 960.09). Note that this PDF is outdated; the method was last revised in 2013, but this is probably darn close to the current effective version: http://bscw.rediris.es/pub/bscw.cgi/d4461343/Desinf3.pdf Note that the PDF also contains a few other methods, including AOAC 966.04, which is used for sterilants with a sporicidal claim. Here is the EPA method for applying AOAC 960.09: https://www.epa.gov/sites/production/files/2018-01/documents/mb-27-02.pdf
 
The sanitizer claims are limited to food-borne pathogens. It is a matter of using organisms that are representative of what one would normally encounter in the application. I don't think one often encounters C. botulinum in their brewing (or food preparation) areas when other sanitary (cleaning) practices are regularly applied. The relatively low pH of beer is not favorable for growth of either of those organisms.

Yes, this is the point! The label we have disscussed does prove that StarSan is a sanitizer, no quesitons here. But is it useful in hombrew applications? Is any other product labeled as sanitizer useful in homebrew applications? Given the sources we went through, I am still convinced that the answer is no to both questions. As it follows from the labels, for the product to be marketed as sanitizer it has to prove 5-6 log reduction in E.Coli and S.Aureus.

Sure, C.Botulinum is not much the case here, I gave it just as an example where StarSan is likely to fail. However, normal homebrewing environment is not limited to E.Coli and S.Aureus, but also B.Subtilis, various kinds of molds and many other nasty stuff. Sure, most likely it won't make you sick, because, as you pointed out, wort is highly selective substratum. But beer quality will suffer, because two (or more) cultures will grow in the fermenter and each will try to make life of the other unbearable by producing various kinds of toxins aimed to killing the competitor (one of those toxins is C2H5OH, which we all like). Of course, the yeast is likely to win the battle, but we will ingest all the byproducts that would spoil taste of beer and our head feeling in the morning. I can even go forward and say, that commercial brewing standards may allow some amount of foreign flora in the end product. But is the point of homerewing to get a cheap commercial grade buzz or to produce a clean and enjoyable product for ourselves?
 
I would like to but I have got no time at work and I leave in June. I will see if I can get some supply validation for some options though.
 
Right I have got some data, I will post when I get home. As it is confidential information I will need to censor it a little
 
If you want to use weak stuff, you can make up your own PAA with distilled 5% vinegar and the typical drugstore 3% peroxide. Its mixed at about the same ratio as is used to make the pickling solution for removing lead from brass. (I don't remember what the ratio is)

From my research, it apparently takes at least 24 hours for the chemical reaction to move forward and the sanitizing power to be in effect. You can't spray a little vinegar and a little peroxide on a surface and expect it to sanitize (even though you will find instances on the internet where people says it works).
How did you test that they reacted? The paper I read suggested that a strong acid (sulphuric) was needed as a catalyst. On the other hand, I remember reading somewhere that with no catalyst, they will react a little bit but not a strong PAA solution (i.e., not suitable for further dilution).

Note for anyone that tries this: the paper that suggested adding sulfuric acid also suggested neutralizing it afterwards. And if you are doing no-rinse, you should use food grade acids and peroxide.
 

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