Starsan going cloudy, acid eating plastic?

[pablo_h]

Like many I've had starsan go cloudy. I usually make up 5-10L and store it into my 20L cube after use.
But it always comes out cloudy when using it again 2-3 weeks later.
Though I have experienced an interesting thing, sometimes I store it in clear plastic bottles, and it never goes cloudy. So is starsan going cloudy in fermenters and my cube because the acid is eating the plastic and getting some colour in it that way?

 

[manticle]

Usually minerals in the water. Should be ok if pH is still right. Otherwise use deionised.

 

[GABBA110360]

i mix up about 70 l in a 80l tropical esky that i use for bottle sanitising etc and even using filtered water .5 micron water it goes cloudy overnight and i just use it as normal to i feel like replacing it.
i do admit i do waste a fair bit it costs 5 dollars to mix the volume i said and i think thats pretty cheap .

 

[pablo_h]

It's just wierd to me, clear plastic = clear starsan (even from the same batch) Opaque plastic = opaque starsan over a few days.

 

[Lyrebird_Cycles]

So is starsan going cloudy in fermenters and my cube because the acid is eating the plastic and getting some colour in it that way?

No. PE (polythene), the polymer in the cube, is not attacked by normal mineral acids.

The more likely cause is PE (translucent plastic with high oxygen transfer rate) -> polymerisation, PET ( transparent plastic with low OTR) -> no polymerisation.

If it's the SDS / SLS that's polymerising I'm not sure how: there are no double bonds in the carbon chain so there's no obvious path. It may be that it needs metal ions in the water to catalyse the reaction. A 0.5 um filter will obviously have no effect on metal ion concentration.

An alternative is that the phosphoric acid is polymerising, some water supplies have polyphosphates added as chelating agents and these may cause nucleation in the presence of oxygen.

One way to tell would be to try to isolate the material that comes out of solution and see if it burns.

 

[Danscraftbeer]

My rule of thumb is basically what the producers say. If its gone cloudy then its soiled somehow. Mix up some new.
I've kept it contained in buckets for weeks, sanitized many components and its stayed crystal clear.
If for example you rinse your bare hands in that solution then it will go cloudy fairly quick. I've tried different food handling gloves and some (latex) will turn star san and equivalents cloudy overnight.
Its so cheap in my opinion I mix new small quantities more frequently than mixing up bulk quantities. I don't like the idea of reusing it too much.

 

[GalBrew]

I make up 10l and store it in a cube, lasts me a year then I will make a new batch. Never had issues with it going cloudy with filtered water or just plain tap water from either Sylvan or Cardinia reservoirs in Melbourne.

 

[zeggie]

It's so cheap, just mix it up fresh each time

 

[pablo_h]

I make up 10l and store it in a cube, lasts me a year then I will make a new batch. Never had issues with it going cloudy with filtered water or just plain tap water from either Sylvan or Cardinia reservoirs in Melbourne.

Yeah but I do have a problem, that's why I started and thread and you didn't.
I used to make 5-10L and store it in a spare empty fermenter or my cube. Seems to go cloudy quickly in those opaque containers.
I've recently started storing in clear old 2L juice containers and it doesn't go cloudy, so I thought I'd ask half question and half comment for others to try if they had similar issues to me and wanted to keep starsan better.
But it's OK now, zeggie thinks it's cheap so I assume they'll send me some free.

Seriously though, It can't be the plastic then, it could be something to do with air for me.
Obviously with me only storing 5-10 L in a 20L cube or 30L fermenter compared to a 2L clear bottle I fill to the brim? It's not the water as the same water stays clear in the clear bottles, but goes cloudy in the cube (or fermenter).
E: I just remembered when I fill (an opaque) spray bottle to the brim, it's clear for a few weeks as well.

When it's in my cube I am not putting hands or gear or anything into it to soil it, it's a cube with a small cap, so only used for storage, ie I'm only wishing to reuse it once, not forever. Most of my usage is from a spray bottle and all that is totally discarded/wastee3: I use that spray bottle for dirty things like my hands, utensils etc.
I just wish to keep the odd large mixed up quantity for 3-4 weeks for one reuse at least, ie sanatise cleaned fermenter, store, use that 2-3 week old starsan batch just to sanatise the precleaned bottles for that same beer 2-3 weeks later, then discard

 

[fungrel]

Usually minerals in the water. Should be ok if pH is still right. Otherwise use deionised.

As long as it maintains a pH of 3.5 or below, it's good to go.

 

[damoninja]

My rule of thumb is basically what the producers say. If its gone cloudy then its soiled somehow. Mix up some new.

Producers say if it's < pH 3.5 it's good to use.

Mine's cloudy almost the moment I mix it.

 

[huez]

Are you referring to the branded 5star Starsan or the cheap knockoff brand that most homebrew shops in australia sells? Possibly a keg king product. I always find that the cheapo one almost always turns cloudy near straight away or within a few hours. I've stored the 5star one for over a month and its still crystal clear. I was under the impression it was the surfactant coming out of the solution. Could be wrong, there's definitely a podcast out there that talks about it specifically.

 

[pablo_h]

Proper starsan.

Anyway, I think I've found out a system.
When cleaning fermenters and storing for bottles for that batch later, it gets contaminated somehow.
So I have to make a new batch just for the bottles at bottling time 2-3 week later.
However that new batch never goes cloudy after rinsing bottles as I store that in juice bottles - as fermenters/cuber big pails etc unavailable due to being used for cleaning or whatever.
I can use that second batch of starsan in the clear juice bottles for heaps of beer bottles over the period of 2-3 weeks and it's not going cloudy unlike the starsan that's been in the fermenters/cube/pails etc

Solution: Get more juice bottles, make a fresh batch to store in clear plastic bottles at bottling time, say 4-5x clear 2L juice bottles full, Treat the beer bottles, funnel back into juice bottles for storage.
Then when ready to use fermenters, pour them into fermenters and not be suprised if it's cloudy/contaminated and need to be discarded. At least I get one re-use out of it.

 

[peteru]

Sounds like you are cleaning your plastic equipment with sodium percarbonate, caustic or bleach cleaner and not rinsing well enough. The residue then stuffs up your starsan.

 

[pablo_h]

It's possible, but I also cleaned the beer bottles and juice bottles the same way...
I was thinking about it this morrning and I actually think it may be due to the strength I mix. I follow bottle directions for making up 10L (about 15ml starsan), but often make it stronger, but it's around that.
When making up for the 2L juice bottles I use about 5ml because it's hard to guestimate anything smaller, so it's a bit stronger; but also 5ml-6ml -7ml, not much visual difference, so it could be a lot stronger.

 

[peteru]

:unsure:

 

[Rocker1986]

I use a syringe to measure out exactly 1.5mL for my litre spray bottle. I don't bother soaking anything in it because I can't see the point for the equipment I use, a spray will achieve the same thing anyway. So I only have a litre spray bottle. Perhaps a syringe might be the go for measuring it out, just get one with a wide needle because the **** is thick. I also use leftover distilled water from my pilsner batches for mixing it up, have noticed since doing this that it seems to foam up more than it did when I used tap water, not that that in itself means anything, but interesting to note.

 

[GABBA110360]

i have mixed up 80 l mixes of starsan @ 1.5 % using 0.45 micron filtered water here in yamba and had it go cloudy overnight mixed in a orange tropical esky food grade but still goes cloudy i dont worry about just use it as normal and no probs so far

 

[Jack of all biers]

I just mixed up a 500ml batch at 1.5% (I have a 2 ml glass pipette and can measure 0.1ml so it's accurate) to sanitize some stuff for a yeast starter just then and made it up in a clean glass jar. Shook it about a bit, put it down and it hadn't touched plastic, but an hour later it was cloudy. So I guess there is some evidence that it's probably not your plastic, but maybe aeration or the water (I used tap water). I'm not bothered as it will still kill most of the bad stuff.

 

[2much2spend]

Like many I've had starsan go cloudy. I usually make up 5-10L and store it into my 20L cube after use.
But it always comes out cloudy when using it again 2-3 weeks later.
Though I have experienced an interesting thing, sometimes I store it in clear plastic bottles, and it never goes cloudy. So is starsan going cloudy in fermenters and my cube because the acid is eating the plastic and getting some colour in it that way?

usually means the water is hard. High mineral content