Some very interesting (and potentially scary) stuff. Apparently iodophor, especially at no-rinse concentrations, isn’t really very effective. Worth a listen.
I can’t review the podcast apparently, but the abstract does provide some indication of their findings.
Hmm, considering that the recommended contact time for no-rinse Iodophor is about 15 minutes, I suppose I’m not surprised that it was ineffective with only 8 minutes contact time. I guess pro-brewers are in a hurry!!
Bell’s brewery did experiments inoculating iodophor and ethanol with various organisms and plating at various contact times. At 25ppm everything was growing out past 8, even to 20 minutes in iodophor. To get to reasonable times they had to go to 75ppm. Ethanol was pretty quick.
Two takeaways upfront:
How did we get here? We (including pros) have relied on data about the effectiveness of iodophor in hospitals against human pathogens and assumed the same guidelines would apply in the brewery. But beer spoilers are different.
What do they prefer? Ethanol for spray bottles, peracetic acid where applicable (which is nowhere in homebrewing.)
And they need to do more experiments.
Denny, I’m with you on personal experience, and I’ll stick with my SOP. But if I ever have an infection I’ll know to try something different to clean up my brewery. (It sounds like Bell’s is going to keep using iodophor in many applications but with eyes open.) And maybe I’ll rotate sanitizers like you do, though that doesn’t seem to address this immediate subject. Unfortunately I can’t buy Everclear in Ohio.
I’ll +1 on the use of Iodophor. Since switching to Iodophor as my primary sanitizer, I’ve stopped finding mold colonies in my fermenter. I would often see them when using only StarSan and that is to be expected since it is not effective at killing mold spores. I’m curious if the various sanitizers used in the MBAA study are effective against mold spores?
I realize that breweries are now concerned about Diastaticus in their breweries. I’m curious if its more resistant to sanitizers than other yeast???
On Diastaicus, it sounds like they had equal results with that and Brett. Not absolutely sure. They also tested lactobacilli with similar outcome. It looks like iodophor is just slower than ethanol across the board, so not suited to spray bottle use.
Martin, once after a summer hiatus, I found mold growing in my Star San bucket!
Maybe I am in the minority, but I always completely fill my containers, and allow to sit for at least 8hrs before dumping and filling, and I use Iodiophor. Have never had any issues with infections or weird things in over 1300 batches. Do I use a lot of sanitizer? Yes. Am I 100% sure everything is dead? Also yes.
Goose, thanks! 175 is probably what you want, as they said 100% laboratory grade ethanol evaporates too quickly. I guess I just have to try a different liquor store.
There’s a podcast (I think it’s Basic Brewing Radio) interview with a rep from the company that manufactures Iodophor. I believe he said that at a concentration of 12.5 ppm, it takes 2 minutes to sanitize.
I’ve been using Iodophor at that concentration for 13 years, and I’ve never lost a batch to contamination.
That said, I haven’t been looking at my homebrew with a microscope. Whatever is surviving the Iodophor contact isn’t causing me any problems though, and I’ve used 3711 quite a bit in the last few years.
Apparently those guidelines were the starting place for the experiment, and they found it not to apply in brewery situations as it might in others. But somehow all of us have had good results. Maybe it comes down to the old distinction between sanitary and sterile. If we get the population of organisms low enough that they can’t compete with our yeast, we’re good enough. I’m just glad to know this, and I think I’ll increase my soak time a little. Not 8 hours, Beerery, I’m not that patient. Just a little longer. 8)
I have never had a contamination problem. I used to only use Starsan until maybe 6 months ago too. When I do use iodophor my ppm count is somewhere between 12.5ppm and 25ppm. Typically I only use iodophor if I have put bugs into a carboy (one carboy had two Brett strains, lacto, pedio, sac). But I also rinse and use Starsan right after, then I spray some isopropyl in to wipe out the foam before I transfer from kettle to carboy.
Also on my brew days I let my carboy soak in hot pbw for 30 or so mins while I shake it around to cover the inside surface (my hot water heater gets water out above 120*, I just know if I fill my sink I can’t leave my hand in the water), and sanitizer for 30-60 minutes. I think the only way to get an actual sterile environment is to apply heat, but sterile isn’t what is really needed anyways.
The only thing I put in a bottle is Starsan, but I don’t depend on that bottle to sanitize effectively, it’s more a precaution if something I just sanitized got slightly dirty or touched the ground
/counter before beer.
Yep! I’ve seen that too. After a while, things do grow in StarSan solution.
It’s clear that we homebrewers have different equipment and timeframes for sanitizing. Pro’s have equipment turn-over and production requirements to meet. Time is of the essence for them.
I just used WB-06 on my wheat beer. I’d not thought about rubbing the fermenter down with everclear prior to next brew to eliminate the Saccharomyces Cerevisiae Var. Diastaticus. I guess I’ll rub down the the jumper hoses and keg once it kicks as well.
Short of relistening to the podcast, I believe they suggested a 70% ethanol solution for spray bottle use, as it would evaporate slowly enough to give a sufficient contact time. The 190 proof might need to be cut. I see the stuff that’s legal here in Ohio is probably 151, so just about right. Makes me think you could use any high proof vodka.
Or just use iodophor in a good, long soak for objects that can be adequately covered, like kegs, parts in a pail, etc. I’m sure something short of Bryan’s 8 hours would do, but if I was concerned about diastaticus I would not begrudge the time. If really worried about cross contamination from that, or Brett, or whatever, why not increase the concentration to 75ppm and rinse?
The real lesson of this presentation is just that we shouldn’t expect 12.5-25ppm for 2 minutes or 10 minutes to perform as advertised, not that iodophor doesn’t kill stuff. It does. Although they point out that, unlike ethanol, the mechanism whereby it kills is not yet understood, which makes it harder to predict its performance.
I grew up on a farm and have a vineyard even today. I also study food, gmo’s, etc. I know that when treating for unwanted pests, bugs or plants, a diversified approach is always superior, biologically speaking. For instance, if I treat for two years in a row with the same pesticide in the vineyard, I absolutely have bugs that the pesticide will not kill at the end of that time. It’s the biggest issue in herbicides policy recently, where we have weeds that cannot be killed - actually first became a problem in your neck of the woods Denney. I cannot imagine that the microbes in a brewery are any different. I usually make sure to use 2 or 3 different kinds of sanitizers throughout the year.
By the way, note that hospitals are now hotbeds for staph in part because of over- reliance on one treatment. Life at the level of microbes adapts really quickly.
Im using Distilled water, Bleach and Vinegar for 3 reasons:
1.) It’s dirt cheap;
2.) @ 1 oz./1 oz. per 5 gallons of water it’s no-rinse;
3.) @ that same concentration and the proper pH, Charlie Talley identifies it as a “stone cold killer”.
Everything I’ve read suggests you’ve got a winner, although pH control (dead-nuts 5.0) is essential to get all the free chlorine in the form of hypochlorous acid at only 80ppm. But it seems almost ideal. I can, however, see how this might be as inconvenient for a commercial operation as some of their solutions (peracetic acid, chlorine dioxide) are inappropriate for us. If I was a little more ambitious and a little more miserly, I could see going your route. Someday.
(Also don’t remember the stability of this stuff. Iodophor can remain effective for hours to days. Derek, how long does it stay effective when properly mixed?))
I’m not sure. The goal is to mix what I need day of and use it then. The test batches I’ve made were right on at pH of 5 with the mix quoted above. Close enough at least.