Change for the worse in Star San longevity? At least in my new bottle...

[ajk]

This thread has a quote from a StarSan employee stating the solution must have a pH below 3.5 AND be clear.  Cloudiness indicates the surfactant has reacted with minerals in the water and become ineffective.  The surfactant renders more permeable the cell walls of the unwanted flora, and the low pH then kills them.

[mugwort]

Thanks everyone for the input, especially ajk for that link to the thread with the additional Star San info.

In this case of an immediate, drastic change in the time-to-clouding observed from one bottle of SS to the next, all I can suppose there is some appreciable difference between the two batches of Star San that I own.  How and why they came to be different is unknown.

What I do know now is that I need to change my usage practices.  I'll immediately start with the suggestion of using distilled water to mix up solutions that go into my spray bottles or in any situation in which I wish to keep the mix beyond a day.

Cheers and happy sanitizing!

[narvin]

This thread has a quote from a StarSan employee stating the solution must have a pH below 3.5 AND be clear.  Cloudiness indicates the surfactant has reacted with minerals in the water and become ineffective.  The surfactant renders more permeable the cell walls of the unwanted flora, and the low pH then kills them.

If that's true, I might consider switching back to Iodophor for everything.  I sanitize my kegs with star san and push it out with CO2 to purge all the oxygen, and by the second keg it's already cloudy.  I have relatively soft water (Ca 28, HCO3 59), and I'm not going to buy 5 gallons of distilled water just for sanitizing.

[tygo]

This thread has a quote from a StarSan employee stating the solution must have a pH below 3.5 AND be clear.  Cloudiness indicates the surfactant has reacted with minerals in the water and become ineffective.  The surfactant renders more permeable the cell walls of the unwanted flora, and the low pH then kills them.

If that's true, I might consider switching back to Iodophor for everything.  I sanitize my kegs with star san and push it out with CO2 to purge all the oxygen, and by the second keg it's already cloudy.  I have relatively soft water (Ca 28, HCO3 59), and I'm not going to buy 5 gallons of distilled water just for sanitizing.

That five gallons with distilled will last for a long time though if you keep it around.  I do the same thing and always have one keg filled with starsan.

[ajk]

This thread has a quote from a StarSan employee stating the solution must have a pH below 3.5 AND be clear.  Cloudiness indicates the surfactant has reacted with minerals in the water and become ineffective.  The surfactant renders more permeable the cell walls of the unwanted flora, and the low pH then kills them.

If that's true, I might consider switching back to Iodophor for everything.  I sanitize my kegs with star san and push it out with CO2 to purge all the oxygen, and by the second keg it's already cloudy.  I have relatively soft water (Ca 28, HCO3 59), and I'm not going to buy 5 gallons of distilled water just for sanitizing.

I use "softened" water (from my Culligan system).  I keep the mixed StarSan solution in a corny keg, and it lasts for anywhere from weeks to months.  A solution made with distilled water would surely last even longer.

[quattlebaum]

This is my H2o profile in Idaho Falls. In the early days when i didnt pay attention to my H20 brews were just off. My starsan immediately clouded when poured into my tap water. Hell $2 for RO water has made a huge difference. It last 3 to 4 months for me and i brew often.
Calcium   66
Sulfate S04-s   12
Magnesium   20
Sodium   27
Chloride   18
Hardness   262
Alkalinity   224
Idaho Falls PH 8.1

[mtnrockhopper]

When I make it with distilled water it stays cloud-free as you'd expect.  It just struck me interesting that when I make it with tap water it clouds up much much quicker than before, and just like mugwort this seemed to have happened coincidentally after using a new 32oz bottle.

Does StarSan lose its acidity over time in storage and perhaps the stuff in my old bottle was "old"?  It takes me a very long time to go through a 32oz bottle.

I've never heard of an acid that looses it's acidity during storage.