Adding surfactant to sanitizer

[piojo]

So I made my own iodophor*, and was wondering if this sanitizer (and all others) need a surfactant. When you shake up some sanitizer in your carboy or bottling bucket, it would be ideal if it coats the surface and keeps it wet. This is why Star San makes foam and teat dip (bulk iodophor for dairies) uses thickeners. Even CIP depends on the surface staying wet, because there's usually not a constant "gallons per second" flow.

When I tried to shake up the sanitizer in my bottling bucket, it stayed almost totally dry. I ended up adding a bunch of surfactant to make it wet, but I don't have a good food-grade tasteless nonfoaming surfactant.

Do all good sanitizers contain a lot of surfactant? When you properly dilute BTF Iodophor, does it fully wet plastics?

* I ordered povidone-iodine powder from taobao. (Sorry, I looked hard but could not find this product on any western web site.) I buffered it to pH=3, warmed it up, and put it on a stir plate for half an hour. I was rewarded with something that looks exactly like iodophor from a phramacy. However, it's totally different than BTF Iodophor, but I couldn't tell you how without a laboratory.

 

[RPh_Guy]

? Sanitizer is very cheap and reusable.

If the surface is both clean and non-porous, necessary contact time is very short.

 

[piojo]

? Sanitizer is very cheap and reusable.

If the surface is both clean and non-porous, necessary contact time is very short.

That's a common claim, but I've never seen any science that supports it. Sanitizers are measured when in intimate contact with the soil (a liquid suspension), never on a hydrophobic (dry!) surface.

Keep in mind that infections are rare, so if you've never had one, it still doesn't mean you are achieving the full log-3 microbial reduction you technically should be. It's also never reusable except in the case of acid anionic rinses like star san.

Soaking is wasteful no matter what sanitizer you are using, and won't reach the crevices where the lid meets the body. And of course it would cost a ton for CIP of big fermenters.

 

[RPh_Guy]

I do mainly use star san for the reasons I mentioned. I reserve iodophor (which is even less expensive) for non-plastic. I don't want stains.

For what it's worth, iodophor uses sodium lauryl sulfate or sodium dodecylbenzene sulfonate or sodium dihexylsulfosuccinate.

 

[piojo]

For what it's worth, iodophor uses sodium lauryl sulfate or sodium dodecylbenzene sulfonate or sodium dihexylsulfosuccinate.

Thanks, that's very helpful! I just shared my formulation for iodophor here, so it's helpful to know exactly what is missing.

How did you narrow down which surfactant it uses? I don't see anything about that in the data sheets or EPA pesticide registration for BTF or IO Star.

 

[RPh_Guy]

The patent
https://patents.google.com/patent/US4088597A/en