Spooky season Friday - ahhhghhh! Botulism !

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Most home brewers bottle and most store them at room temperature. I keg now, but I've brewed hundreds of gallons of beer that I bottled and stored at room temperature and botulism is something that never even crossed my mind. I've not only never met a homebrewer who got botulism, I've never even heard of one.

I'm a pretty OCD guy myself, so I have thought about the risks of botulism before... just never in association with beer. I can't even imagine how wort or beer could produce botulism. Before fermentation starts, there's likely too much oxygen there for it to happen, plus it's at too cool of a temperature. Then once fermentation starts, the pH drops drastically and you've got ethanol being produced. It's just an extremely inhospitable environment for it.
I wonder what's the longest you've left at room temp in bottles? I have a batch I bottled in April and have been off and on in fridge and room temp. Been a couple of weeks at room temp though and I'm skeptical. I used pH strips and it's definitely a bit high but I suspect the pH strips are inaccurate.
 
I wonder what's the longest you've left at room temp in bottles? I have a batch I bottled in April and have been off and on in fridge and room temp. Been a couple of weeks at room temp though and I'm skeptical. I used pH strips and it's definitely a bit high but I suspect the pH strips are inaccurate.
3 years.
 
Did it taste good? I've heard flavor begins to suck...
It was a lambic-style sour that kept getting more and more sour very very slowly in the bottle, so the pH of the last bottle I drank was probably around 3.4 to 3.5. I bottled it after almost a year in a tertiary glass carboy and it was pretty sour at that point, but it got progressively more sour as time went on. I love sours, so I thought it tasted better after 3 years than it did early on.
 
So I've learned that some styles like IPA and pale ales typically finish closer to around 5 pH. The alcohol probably still a problem for the bacteria
 
It was a lambic-style sour that kept getting more and more sour very very slowly in the bottle, so the pH of the last bottle I drank was probably around 3.4 to 3.5. I bottled it after almost a year in a tertiary glass carboy and it was pretty sour at that point, but it got progressively more sour as time went on. I love sours, so I thought it tasted better after 3 years than it did early on.
I guess that's a bit different non-sours being that pH can be higher.
Just reading about pH level of certain beers, some beers like pale ales get close or higher than 5 pH which is enough for growth of the bacteria. Of course alcohol content likely counteracts that
 
I guess that's a bit different non-sours being that pH can be higher.
Just reading about pH level of certain beers, some beers like pale ales get close or higher than 5 pH which is enough for growth of the bacteria. Of course alcohol content likely counteracts that
At this point, I'm not sure if there's anything we can do to convince you otherwise, so it might just be best to give up homebrewing altogether. But to sum up, alcohol, pH, and hops' antibacterial effects make botulism incredibly unlikely. Boiling your beer after it's done is just going to ruin it, so if you're considering doing that, just stick to commercial brews and find a different hobby.
 
I have had Westvleteren 12 (belgian trappist quad) bottles from 0 to 10 years old. I'd say the best bottles were 3-5 years old. Definitely 7+ shows its age, but is still drinkable.

I've heard some big barleywines are still good after 10 years.

Hoppy beer shows age much faster.
 
I can a lot of garden vegetables. Botulism is on my radar. It only takes about 150°F to destroy the toxins. However, the spores are a little harder to kill. The good news is that healthy adults can tolerate the spores without adverse effects. I suppose that there are limits to this.
As mentioned, it takes extreme temperatures to kill the spores, and even freezing temperatures won’t kill them. Acidic conditions are a problem for them, so pickles, tomatoes, etc only require water bath canning. Low acid foods like green beans require pressure canning to achieve the high temperature above the boiling point.

Use your Starsan, be clean, RDWHAHB!
 
I can a lot of garden vegetables. Botulism is on my radar. It only takes about 150°F to destroy the toxins. However, the spores are a little harder to kill. The good news is that healthy adults can tolerate the spores without adverse effects. I suppose that there are limits to this.
As mentioned, it takes extreme temperatures to kill the spores, and even freezing temperatures won’t kill them. Acidic conditions are a problem for them, so pickles, tomatoes, etc only require water bath canning. Low acid foods like green beans require pressure canning to achieve the high temperature above the boiling point.

Use your Starsan, be clean, RDWHAHB!
I can jalapenos with vinegar and no heat. pH works great. 1/3 vinegar, 2/3 water, last forever. Pickling FTW.
 
I can jalapenos with vinegar and no heat. pH works great. 1/3 vinegar, 2/3 water, last forever. Pickling FTW.
I do jalapeños as well. I do 50/50 vinegar and water with a 10 minute boiling water bath. I have had jars for years and opened them up and had no problems. 🤷🏻‍♂️

Edit: Typo; only a 10 minute water bath. I don’t want mush!
 
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I also thought some more about how ridiculous this is. Humans have been brewing and drinking beer for around 14,000 years. It is either the third or fourth most drank beverage on the planet right now. Homebrewing today is far more safe and consistent than professional brewing from hundreds or thousands of years ago where no one knew about yeast, bacteria, or so on, and beer was generally considered safer than water back then. And in those days, spontaneous fermentation was the norm where you let all the microorganisms into the wort.

Being OCD is one thing, but this is like being terrified of making wine because you think the French government will sue you for encroaching on their domain.
 
I also thought some more about how ridiculous this is. Humans have been brewing and drinking beer for around 14,000 years. It is either the third or fourth most drank beverage on the planet right now. Homebrewing today is far more safe and consistent than professional brewing from hundreds or thousands of years ago where no one knew about yeast, bacteria, or so on, and beer was generally considered safer than water back then. And in those days, spontaneous fermentation was the norm where you let all the microorganisms into the wort.

Being OCD is one thing, but this is like being terrified of making wine because you think the French government will sue you for encroaching on their domain.
I'm not saying it's rational, actual clinically diagnosed OCD, the 0.00000001% chance of it happening means its stuck in the back of my brain forever and ever.
I am however appreciative of everyone's encouragement to keep brewing on and that does help. I will likely keep brewing because I do like it enough to do so.
Also the people thousands of years ago had a lot more to worry about than beer. Life expectancy was like 30 years old and there was death in every food so you kinda were probably pretty used to being blindsided by sickness
 
So would a lot us on here, but we prefer the term; "Detail-Oriented". :p
I suggest simply refraining from brewing in the event of incarceration and in the meantime; a form of active cognitive therapy:
Here's a pic of botulism that you can base a halloween costume on...focus on the fun in translating the image into a human-wearable outfit:
View attachment 859215
🎃 :mug:
Looks like oatmeal with blueberries.
 
I wonder what's the longest you've left at room temp in bottles? I have a batch I bottled in April and have been off and on in fridge and room temp. Been a couple of weeks at room temp though and I'm skeptical. I used pH strips and it's definitely a bit high but I suspect the pH strips are inaccurate.
I made a Christmas Ale many years ago. A small batch with only about a dozen bottles. I let the bottles sit in my closet for 12 months before ever chilling and cracking one open. We consumed about half that first holiday season and I left the rest in the closet and my wife and I enjoyed one every Christmas for the next three years.

I think you need to let go of this PH bone and move on. Between boiling the wort, the environment produced by the yeast... low oxygen and the presence of alcohol... a natural deterrent is formed that inhibit and is even inhospitable to bacteria... including clostridium botulinum.
 
What's that you say? Leaving beer at room temp for a long time? Say it ain't so!

averyfeatured.jpg
 
I’ve quit worrying about contracting botulism from homebrew. Now I worry about dying when a meteorite crashes through my roof while I’m hiding under the bed during the zombie apocalypse. I mean, the odds of that happening must be at least an order of magnitude greater than getting botulism from homebrew, amirite? 😉
 
I’ve quit worrying about contracting botulism from homebrew. Now I worry about dying when a meteorite crashes through my roof while I’m hiding under the bed during the zombie apocalypse. I mean, the odds of that happening must be at least an order of magnitude greater than getting botulism from homebrew, amirite? 😉
Yeah😅😂
I'm not exactly rational. I know that. Albeit I feel a bit better about it
 
What's that you say? Leaving beer at room temp for a long time? Say it ain't so!

View attachment 859375

And then there were the yards at the largest breweries in the world, Barclay Perkins and Whitbread, in London. Stacks and stacks of barrels of beer left OUTSIDE in all seasons and all weather for 12 months. Or the mammoth porter vats that held beer for 12 months. Not just dark beers either... this photo was captioned "Pale Ale Cellar" from the Eldridge Pope brewery.
 

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What's that you say? Leaving beer at room temp for a long time? Say it ain't so!

View attachment 859375
Yes, barrel aged is a thing, but a lot of those are higher alcohol. I'd be more worried about low alcohol (less than 6% beer), high pH sitting at room temperature in low oxygen places with seals.
I should note, I'm getting this from scientific journals where they tested whether the toxin could form in specific environments and they observed that the toxin was present when pH was high enough and alcohol content was low enough. So this isn't just theoretical... It has happened
 
Tannins extracted from oak barrel staves have preservative/antiseptic properties, as do hops. They can suppress the production of toxins from botulism spores, like alcohol does, but does little to destroy the spores that actually produce those toxins. As has previously been stated, destruction of the spores requires exposure to 240F temperature for that to occur.
 
Tannins extracted from oak barrel staves have preservative/antiseptic properties, as do hops. They can suppress the production of toxins from botulism spores, like alcohol does, but does little to destroy the spores that actually produce those toxins. As has previously been stated, destruction of the spores requires exposure to 240F temperature for that to occur.
Yeah, I haven't read much research done from hops, but I can imagine that is a big thing that prevents the growth of the bacteria (and subsequent toxins)!
 
When first getting involved in homebrewing many years ago, I received the reassuring wisdom that food safety was not a concern. Apparently, that was only mostly true. Dang!

However, given all I've read here, triggered by @zosimus's concerns, it seems that if I make fresh starters and don't make low-ABV and oddly high pH beers, the old wisdom is still entirely true.
 
Yes, barrel aged is a thing, but a lot of those are higher alcohol. I'd be more worried about low alcohol (less than 6% beer), high pH sitting at room temperature in low oxygen places with seals.
I should note, I'm getting this from scientific journals where they tested whether the toxin could form in specific environments and they observed that the toxin was present when pH was high enough and alcohol content was low enough. So this isn't just theoretical... It has happened
Kinda odd how your definition of "low alcohol beer" is "less than 6%." 4% to 6% is the most common ABV range on the planet for beers, and thus "average alcohol beer." 90%+ of the beers sold around the world are in between 4% and 6% ABV (most mainstream lagers are typically around 4.5%, 5%, or 5.5%). I don't consider something "low alcohol" unless it's under 4%. Most of the beers I make nowadays are between 3% and 5% ABV. I only consider it low alcohol if it's under 4%.

Although 3% ABV beers aren't as common nowadays, in the past, whenever a brewery made a beer, they would also make a "small beer" from the second runnings. This was typically drank instead of water and was in between 0.5% and 3% alcohol. Were brewers all getting botulism from their low-ABV higher-pH small beers they were drinking with every meal?
 
Kinda odd how your definition of "low alcohol beer" is "less than 6%." 4% to 6% is the most common ABV range on the planet for beers, and thus "average alcohol beer." 90%+ of the beers sold around the world are in between 4% and 6% ABV (most mainstream lagers are typically around 4.5%, 5%, or 5.5%). I don't consider something "low alcohol" unless it's under 4%. Most of the beers I make nowadays are between 3% and 5% ABV. I only consider it low alcohol if it's under 4%.
I am only saying 6% because that is the threshold for the bacteria growth for C. Botulinum which causes botulism.
Above 6% inhibits growth of the bacteria entirely.
So 'low' is more relative to the fact that the bacteria can grow if it is less than the 6%
 
I am only saying 6% because that is the threshold for the bacteria growth for C. Botulinum which causes botulism.
Above 6% inhibits growth of the bacteria entirely.
So 'low' is more relative to the fact that the bacteria can grow if it is less than the 6%
I'm more likely to get botulism from honey than from low-ABV, low-pH beers, but I still eat honey quite often.

Also, for reference:
https://en.wikipedia.org/wiki/Small_beer
 
I'm more likely to get botulism from honey than from low-ABV, low-pH beers, but I still eat honey quite often.

Also, for reference:
https://en.wikipedia.org/wiki/Small_beer
Honey is known to often have the spores that cause botulism. The spores themselves are practically harmless to us because our bodies can filter them out. However, infant botulism exists because infants have not developed those anti-bacterial mechanisms, so it is possible for bacteria to grow in an infants stomach thus creating the toxin.
The bacteria itself is not the cause of Botulism, it is when the spore begins to reproduce that a separate toxin is excreted and it is the toxin that causes botulism.
The bacteria's spore is found on honey, but it does not grow (thus creating the toxin) for a few reasons. One is that honey is too acidic (under 4.6pH) , two is that honey is to syrupy (not enough water content) and three, honey does not have the necessary proteins necessary for the bacteria to begin to reproduce, thus inhibiting any form of growth and toxins to form. Not to mention honey is typically not sealed away from oxygen which also prohibits growth. There is virtually no risk in meads due to those reasons. Beer on the other hand, meets many of the thresholds for the bacteria's growth including the necessary proteins and higher pH
Note: Our bodies do not filter out the toxin and it is incredibly deadly, thus if the toxin exists before it reaches our stomachs, our bodies will be affected (unlike with just consuming the spores)
 
Also here is a study done on the risk of pathogen in low alcohol beers. It is a real risk
https://www.sciencedirect.com/science/article/pii/S0362028X23068679
I'm not going to disagree with the honey part because my point was that there's virtually zero risk of me getting botulism from honey, which ACTUALLY causes botulism quite often (almost always in infants). You can come up with theoreticals for botulism from beer, but you can't actually give a single example of anyone ever having gotten botulism from beer. I'm not saying it's impossible, but it's incredibly unlikely.

I'll also note that the definition of "low alcohol beers" in that study is actually low alcohol such as 0.5% or 1% and not "below 6%" like you theorized. And yes, if you were making 1.5% ABV beer with a high pH, using no hops, and containing little to no CO2 (carbonic acid also lowers pH), then sure, you'd be increasing the risks of it, but even that study is not saying that foodborne pathogens are likely to survive. It actually states that multiple times right from the beginning. It even gives the range of "Traditional ethanol concentration" as 3.5% to 5.0% as making it safe. The 17ppm it mentions would be around 10 IBU, which is a relatively low bittering level (hence why sour beers traditionally have IBUs below 10 IBUs because they don't want the hops to stifle bacterial growth).

I know that you realize botulism in beer is incredibly, incredibly, incredibly unlikely, but you sound like you're trying to convince yourself that it's much more likely than it actually is.

Beer is generally considered safe from foodborne pathogens due to several intrinsic and extrinsic hurdles. These traditional hurdles include ethanol concentration (typically 3.5–5.0%), hops bitter acids (approx. 17–55 ppm iso-alpha acids), low pH (approx. 3.9–4.4), high amounts of dissolved carbon dioxide (2–2.5 v/v), low oxygen (<0.1 ppm), and lack of nutritive substances (Leistner, 2000, Menz et al., 2009). In addition, processing methods such as mashing, wort boiling, pasteurization, sterile filtration, and cold storage provide further protection against harmful microorganisms (Menz et al., 2011).
 
The average pH of honey is 3.9. The range of honey. Typical range is 3.4 - 6.0, according to U.C. Cal/Davis.
The production of the toxin that causes botulism from honey does not occur in the packaged honey but in the stomach of the person who consumed it. This is largely believed to be due to the immune system being unable to prevent this. It mostly happens in infants under 1 years old because their immune system hasn't developed the proper defenses yet, but it very rarely also occurs in adults (known as adult intestinal toxemia).
 

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