Starsan shelf life in a bottle

[KernelCrush]

Bought a 32 oz bottle last October.  Got a new bottle yesterday.  The color difference is startling (it scared me anyway). https://www.dropbox.com/s/0b27kcd030bheyd/2014-11-22%2008.33.14.jpg?dl=0 I use RO for mixing and the old bottle once in solution was going cloudy immediately, within 5 minutes.  pH was still fine but hard to see small items in my soaking bucket.  Will save the old bottle for paint removal on beer bottles.  A several day soak takes the paint off Stone IPA bottles.

[brewfun]

Are you making the RO water or buying it? The cloudiness would seem to indicate minerals are in the water. RO membranes can load up and some minerals can get through. Check it with a TDS meter.

The color is a reaction by the phosphoric acid with oxygen and heat. It doesn't reduce the effectiveness of the Starsan.

[KernelCrush]

I am making the RO.  First thing I did when that cloudy started was get a check from Wards.  No change there.  TDS 19.  The cloudy its a misconception on many boards, even though 5Star dispels the myth on every single podcast.  It was just inconvenient for me in a StarSan cooler, pH was in the 2's.  Glad to hear the color change in the bottle just caused by oxygen/heat, its been in the brewbarn all summer in FL.  Maybe it should get refrigerated...But it must be the oxygen causing it, my phosphoric 85% bottle hasnt change color in 2 years or more.

[KernelCrush]

The more I think about it it must be the oxygen, cause I leave the caps loose so the bottle doesn't collapse.  When that happens you need to be Hercules to draw an oz.

[texasdan]

I'm thinking you have more than an oxygen problem going on here.  I think there might be heat/temp changes going on if the bottle is collapsing.  I keep my caps closed, at room temps.   A bottle lasts me between one and two years and I have never had a color change.  Caution:  If you have children you need to take proper precautions on storing this product.

[KernelCrush]

I guess collapsing was an exaggeration, the sides just go concave and stay that way after squeezing if I tighten down the caps.  If I leave the caps loose the sides eventually return to their convex shape again.  Maybe I just squeeze too hard.

I was never concerned about storing my stuff, theres a lot more harmful things I use than starsan. Part of my business is commercial access control...no one is getting in my brewbarn, and I never had kids.

I read or heard somewhere that to dispel the myth of toxic starsan one of the 5star employees I think it was Charles Talley the owner, actually drank it neat on the air to prove his point. 

[texasdan]

Are you sure one of the caps is not cracked cap around the top...  That happened to me once when I tightened it too tight.  I could never get the right vacuum after that. 

[KernelCrush]

I 've had that happen before too, but no, the caps are good.  Every bottle does the same thing.

[Scott Ickes]

The bottle I'm using now is hard to get the starsan up into the measuring chamber.  I don't know why either.

[KernelCrush]

We must not know our own strength!  Its like...golly...this shouldn't be that difficult.  I am thinking it has to do with once the sides cave in theres not enough air left in the bottle to push it up the feed tube.

I am back to square 1.  The brand new bottle clouded up almost as quickly this morning in RO water.  So its not the water, its not the starsan, so I bleached out the starsan cooler and tried again.  same.  cleaned and filled a corny.  same.  Filled a kettle.  same thing.  I'll try to get some store RO tomorrow and try it again.  I used to be able to keep starsan for a very long time with no clouding, I usually only discarded it when I got sick & tired of looking at it.

[KernelCrush]

The cloudiness would seem to indicate minerals are in the water.

So it is the water.  What would make the dodecylbenzenesulfonic acid fall out?  From what I understand it is basically a detergent and its only purpose is a bonding or sticking agent, I forget the exact term for that at the moment.  Its the same as what makes weed killer work.  The brewers test at wards came back basically unchanged from any previous. Obviously didn't test for the mineral I am getting.  This pic is about 30 seconds after adding starsan to store bought RO and my RO.  The 5 G carboy is my RO with phosphoric 85% only.

https://www.dropbox.com/s/k3h8lq7bznfex6j/2014-11-24%2019.40.42.jpg?dl=0

[KernelCrush]

the word I couldn't remember is surfactant