- Cooling wort / No-chill / Botulism?

Homebrew Talk

Help Support Homebrew Talk:

This site may earn a commission from merchant affiliate links, including eBay, Amazon, and others.
Here are a few... It appears more hoppy beers (ones done with dry hops especially) also raise the pH level.
I could be wrong, but I did test a few beers (pilsner and stout) I had in my fridge and noticed they were closer to 5pH (using a pH strip test so maybe less accurate

I would be curious to see more experiments though and from looking just now, there isn't a whole lot of data on finished beer pH I can find. Still looking though.

https://www.oculyze.net/the-beer-acidity-chart/
https://scottjanish.com/a-look-at-ph-in-hoppy-beers/
https://atlas-scientific.com/blog/ph-of-beer/
The first link uses the third link's data. The third link is is a site trying to sell you pH equipment. I'm not saying the information is incorrect but it's pretty weak as far as how and what was measured. I'll read the Janish article at some point. I have six beers kegged, maybe I will test them if I get a chance. Three IPAs, an Octoberfest, a Schwarzbier, and an Irish Stout.
 
The first link uses the third link's data. The third link is is a site trying to sell you pH equipment. I'm not saying the information is incorrect but it's pretty weak as far as how and what was measured. I'll read the Janish article at some point. I have six beers kegged, maybe I will test them if I get a chance. Three IPAs, an Octoberfest, a Schwarzbier, and an Irish Stout.
Yeah I do see that it's questionable data, but it was the only data I could find. I also found a few forums talking about keeping the post boil pH closer to 5. I'm not sure how far pH is typically dropped at end of fermentation if at all
 
It does appear people who brew IPA shoot for. 5.0pH post boil and add acid knowing that dry hopping will increase pH
Some people do this, but I'm not sure that it's actually a common practice.
I'm not sure how far pH is typically dropped at end of fermentation if at all
My biochemistry is more than a little bit rusty, but IIRC most of the drop in pH actually happens during the growth phase as a result of nitrogen assimilation which produces organic acids.
Yeah I do see that it's questionable data, but it was the only data I could find.
Bad data isn't really any better than no data.
 
Yeah I do see that it's questionable data, but it was the only data I could find. I also found a few forums talking about keeping the post boil pH closer to 5. I'm not sure how far pH is typically dropped at end of fermentation if at all
There are a lot of observations in that thread you linked to in post #39. While the final pH may be interesting for reasons other than botulism, I don't find one alleged case of botulism in homebrewing to be of much credibility given the many active homebrewers there are in the world. And let's face it, not everyone sanitizes sufficiently and once in a while may get an infection, yet botulism poisoning is still not happening. You'd be getter off chasing down some other rabbit hole for perfecting your brewing. You really have to hit the trifecta to get food born botulism in canning even, with canning having a much wider set of products to muck up.
 
There are a lot of observations in that thread you linked to in post #39. While the final pH may be interesting for reasons other than botulism, I don't find one alleged case of botulism in homebrewing to be of much credibility given the many active homebrewers there are in the world. And let's face it, not everyone sanitizes sufficiently and once in a while may get an infection, yet botulism poisoning is still not happening. You'd be getter off chasing down some other rabbit hole for perfecting your brewing. You really have to hit the trifecta to get food born botulism in canning even, with canning having a much wider set of products to muck up.
I'm not changing any processes to my brewing. I'm not really worried about botulism anymore. I'm more just interested. Like if I happened to be a microbiologist right now, I would be curious to do this more as a research project to disprove myself (my previous worries). Like yeah I started off this forum feeling like it was a risk, and now I know it's not much of any risk, I'm just curious given what I've read about conditions. Like I was satisfied with answer that the reason it's not a problem is because beer is below 4.6pH but that doesn't seem to always be the case, so then my question would be, why? More just interested. I am more curious and will research more about hops. Like I know it's kind of a pointless because it shouldnt matter, but these kinds of things interest me is all
 
Bad data isn't really any better than no data.

Yeah, I see that now, but I haven't seen much data to the contrary and my tests with my beer at home did suggest higher pH. So ill look into it more..the forum posted did show IPA at 5 pH
 
I'm not changing any processes to my brewing. I'm not really worried about botulism anymore. I'm more just interested. Like if I happened to be a microbiologist right now, I would be curious to do this more as a research project to disprove myself (my previous worries). Like yeah I started off this forum feeling like it was a risk, and now I know it's not much of any risk, I'm just curious given what I've read about conditions. Like I was satisfied with answer that the reason it's not a problem is because beer is below 4.6pH but that doesn't seem to always be the case, so then my question would be, why? More just interested. I am more curious and will research more about hops. Like I know it's kind of a pointless because it shouldnt matter, but these kinds of things interest me is all
I read some of your other posts in the other thread. I will attempt to help you as to why the toxin is not present in homebrew. In order for the bacteria to produce the toxin, it needs to be in its niche. Suppose only two conditions are important for the organism's niche. For simplicity, we will make these conditions measurable on a continuous scale. We plot one condition on the x-axis and one on the y-axis. This will form a plane on the graph which is the organisms niche. Example, the values for condition 1 are 5-10, and for condition 2 also 5-10, this will form a square flat region on the XY plane. Now, add in a third condition and a z-axis and for simplicity again the range is 5-10. Now you have a cube. Now we can't really draw another dimension but each condition that is important will have its own axis and a hyperdimensional region of space, a hyperdimensional cloud will describe the niche of the bacteria. Homebrew does not fall in that cloud. Your mistake is considering the various conditions separately or perhaps somewhat in context to the other conditions but not all at once. The full niche is where the bacteria can reproduce, including creating the toxin. Given the number of times people have reproduced the experiment of creating beer, it does not seem at that homebrew is any where near the niche.
 
I read some of your other posts in the other thread. I will attempt to help you as to why the toxin is not present in homebrew. In order for the bacteria to produce the toxin, it needs to be in its niche. Suppose only two conditions are important for the organism's niche. For simplicity, we will make these conditions measurable on a continuous scale. We plot one condition on the x-axis and one on the y-axis. This will form a plane on the graph which is the organisms niche. Example, the values for condition 1 are 5-10, and for condition 2 also 5-10, this will form a square flat region on the XY plane. Now, add in a third condition and a z-axis and for simplicity again the range is 5-10. Now you have a cube. Now we can't really draw another dimension but each condition that is important will have its own axis and a hyperdimensional region of space, a hyperdimensional cloud will describe the niche of the bacteria. Homebrew does not fall in that cloud. Your mistake is considering the various conditions separately or perhaps somewhat in context to the other conditions but not all at once. The full niche is where the bacteria can reproduce, including creating the toxin. Given the number of times people have reproduced the experiment of creating beer, it does not seem at that homebrew is any where near the niche.

I have considered this. I think in the other post, I mentioned the 'combination' of factors that prohibit growth, so like your graph cloud of different niche's.
For simplicity sake, let's just leave this at 2 dimensions and we can add further dimensions later. If the substance is above 4.6 pH, it technically can be in the cube, but it might not have right Y value to call into the cube. So it also needs less than 6% alcohol to fall into that cube. If both of those values are met then it falls into the cube. But let's say that's variable. We do know that 4% abv *begins* to stunt the growth of the bacteria (not entirely) so the y axis is probably not a straight line or there is a gray area of probability. So above 4% and below 6% alcohol, you'll have a grayer area of probability. The bacteria could grow, but it is less likely to do so the higher it goes (so a slope of sorts). Now from my research, I'm not sure if probability slopes as pH goes up or if there is a cap of probability. But I think the bacteria prefers base and not acid so I would assume it begins slope. Below 4.6 though completely prohibits growth and 4.7 doesn't, but maybe it is a lot less probable than when pH is 5.5.
So about probability, I completely agree. The combination of different factors probably decreases likelihood to very low probabilities (or complete inhibition). Like if beer has 5.0ph and 5.5% alcohol, it is way less likely than something that has 5.0ph and 3.9% alcohol. And something 4.4pH and 6% alcohol is also very very unlikely.
One of the scientific journals I read noted that if even one inhibitory factor was removed, the likelihood would go up. (They noted something like pH being >4.6pH) Thus getting us a lot closer to the theoretical cloud. I'm not saying we ever reach that cloud, but as you noted, experimentation suggests that we don't ever get to the cloud.. I'm sure a low abv (1-2%) high pH beer is a heck of a lot closer to the threshold than normal beer.
But yeah I'm totally on board with that concept that there's a lot of variables that push it away from the cloud. I'm more curious what all those variables are (like what is the threshold IBU that completely inhibits growth). Because I'm not sure it's *just* alcohol and pH.
For instance, the FDA only considers one variable (pH) when making recommendations for home canning. Now canned foods aren't typically alcoholic, but if they were, I'm sure they would include that as a factor and if they did they would probably suggest that you either have at least 6% alcohol or below 4.6 pH. Maybe at that point they'd even have a combination range like as long as you have 4% and less than 5.5pH you're good or something like that.
That could be the case but there's not much research on that or combination factors.

All of this would depend on whether there was a slope of likelihood and cut offs. Like from the articles I've read we know below 4% abv, the bacteria completely resists (and grows) but above 4% it begins to struggle. I'm unsure if it's the same for pH or if there's a cut-off. Like above 4.6pH, it could have no struggle at all and likelihood would be the completely same whether it was 5.3 or 6.8.
So under 4%abv, the inhibitory factor is completely removed as a variable because it has no effect on the bacteria

Okay new info: I have read a small amount and it appears likelihood remains close to the same around 5-7pH and from 4.6-5 there is a drop in probability and requires incubation for longer.
Then below 4.6 it is pretty much completely inhibited. So there is the curve from 4.6-5 and then it kind of levels out at 5. So there would be negligible difference in probability between something at 5.3 or 7.0pH, it appears
 
Last edited:
I have considered this. I think in the other post, I mentioned the 'combination' of factors that prohibit growth, so like your graph cloud of different niche's.
For simplicity sake, let's just leave this at 2 dimensions and we can add further dimensions later. ...
No. They are all important at the same time. If you want to investigate some you still need to control the others. And honestly I'm not seeing the level of rigor on your part necessary to make your claims as you haven't referenced much original research. You are just talking it through without concrete data or a plan to properly investigate it. You went from removing an inhibitory factor to "getting us a lot closer to the theoretical cloud". That's biased. You didn't even name the factor. But for what anyway? For something that only happened maybe once? Definitely not interesting enough for me to spend much time on myself, this is about my limit.
 
Back
Top