Negative Pressure in Carboy Issue

[Pizombie]

Been fermenting cider for awhile but never had this problem before as southern California weather is typically pretty stable. I have two garaged carboys (5 gal and 6.5 gal) going about 5 weeks in now with blowout tubes to a single gallon jug of star sans solution. Over the holiday the temp dropped a good ten degrees (low from 50 to 40) along with a good rainstorm for about two days. Apparently the pressure and temp change was enough to pull up at least a half gallon of solution into the carboys. Has anyone had this issue and was able to recover? I hoping the batch isn't ruined but I've never dealt with more than a few drops ever coming coming back into the cider. The first picture shows how the setup has been sitting with the red lines showing the increased amount. The 5 gallon seemed to get more of the solution than the larger carboy. Any advise would be welcome on how to proceed.

 

[Coldfrog]

Been fermenting cider for awhile but never had this problem before as southern California weather is typically pretty stable. I have two garaged carboys (5 gal and 6.5 gal) going about 5 weeks in now with blowout tubes to a single gallon jug of star sans solution. Over the holiday the temp dropped a good ten degrees (low from 50 to 40) along with a good rainstorm for about two days. Apparently the pressure and temp change was enough to pull up at least a half gallon of solution into the carboys. Has anyone had this issue and was able to recover? I hoping the batch isn't ruined but I've never dealt with more than a few drops ever coming coming back into the cider. The first picture shows how the setup has been sitting with the red lines showing the increased amount. The 5 gallon seemed to get more of the solution than the larger carboy. Any advise would be welcome on how to proceed.
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I’ve had it happen before with cider (accidentally unplugged fermenter controller and temp dropped). I sucked approximately 2-3 pints into a 5 gallon batch with no ill effect. The final product had no noticeable difference in taste (house recipe I’ve made a dozen times - so I know what it should taste like) and no ill health effects among the 10 of us that drank it.

 

[A-man]

I wouldn't ingest Star San: https://www.jstrack.org/brewing/msds/starsan.pdf

 

[MarkKF]

I wouldn't ingest Star San: https://www.jstrack.org/brewing/msds/starsan.pdf

So why does it advertise no rinse?

I would only use a blow off or three piece airlock during (very) active fermentation. After that I switch to a bi-directional “S” airlock.

 

[A-man]

So why does it advertise no rinse?

That's a good question. After I posted this AM I did further research on one of the active chems in Star San, dodecylbenzenesulfonic acid, and I would be even less inclined to use it at all now. I sure as hell wouldn't drink anything with a half gallon of Star San solution in it.

 

[Maylar]

I always rinse starsan off with clean water, and use vodka in airlocks.

 

[Pizombie]

I have plans for secondary fermentation so I was more worried about the batch being ruined in the flavor/fermentation direction than being safe to drink. While drinking the star sans solution undiluted (ph of 1) is dangerous, it's heavily diluted when you prep it for actual use (pH of 3.8). The directions say to use 1 ounce of solution in 5 gallons of water. I typically make a gallon at a time so I usually just make sure to stay under the 1/4 ounce mark on the bottle of star sans when I add it to the water. Running the math, even if I round up to a full 1/4 ounce pure solution added to a rounded down 100 ounces of water (full gallon is 128 ounces) to account for some evaporation over the weeks the setup has been sitting, the solution that got sucked back into the carboys at worst had a pH of about 3.5-3.6. That's in the range of the apple juice I started with.

 

[theinterneti]

Despite the warnings in the materials sheet, starsan is pretty innocuous stuff. Watch out for the undiluted stuff, don't drink THAT.

I would be really surprised if it affected the flavor, starsan is 50% phosphoric acid and that gets used in soda!

Watch out though, 25% of starsan is unknown components and those could be quite bad for you.

 

[Sequoiacider]

That MSDS is for undiluted Star-San. At actual usage dilution you can (practically) drink it. Those of you who are saying you are wary about using it will therefore never want to go to restaurants or bars, as star-san (and similar products) are used as no-rinse sanitizers on almost everything in the commercial food and beverage industry.

I have heard many stories about people getting some star-san suckback into their beers/ciders. It is less than ideal and should be avoided. It may have an effect on the taste, but it definitely will not ruin it.

To help avoid it in the future, you should put your carboys a few feet elevated from your blowoff reservoir. The extra elevation will help prevent the negative pressure from pulling the starsan into your fermenter. It may still happen if there is an extreme temp change, but will definitely help.

 

[A-man]

That MSDS is for undiluted Star-San. At actual usage dilution you can (practically) drink it. Those of you who are saying you are wary about using it will therefore never want to go to restaurants or bars, as star-san (and similar products) are used as no-rinse sanitizers on almost everything in the commercial food and beverage industry.

I have heard many stories about people getting some star-san suckback into their beers/ciders. It is less than ideal and should be avoided. It may have an effect on the taste, but it definitely will not ruin it.

To help avoid it in the future, you should put your carboys a few feet elevated from your blowoff reservoir. The extra elevation will help prevent the negative pressure from pulling the starsan into your fermenter. It may still happen if there is an extreme temp change, but will definitely help.

Yes, the MSDS for undiluted Star San carries the warning for mucosal erosion. There is nothing re: dodecylbenzenesulfonic acid
and it's long-term effects, the easily obtainable published literature for which is notably lacking. As noted, the metabolism of this chemical would be of interest at it contains the molecule benzene. The concern is mine and apparently mine alone so don't let me poo poo anybody's Star San party.