Low alcohol beer... botulism?!

[ryderkellan]

Recently started attempting to make low-alcohol beer, inspired by @peebee accounts of 'brewed' low alcohol brews, rather than boil-off. I've done a cold mash and got down to a thrillingly weak OG1018! Way-hey.

Having left the thing to ferment, I of course started reading loads of forum posts. On one hectic US forum there's a load of stuff about the risk of botulism. Is this something I should be worried about? @peebee is this on your radar?
I gather the thing to do is check the pH, so I've got some pH strips on order. I'm not hugely keen on dumping a load of acid in my beer. Does anyone have recommendations for adjusting pH? (Words of one syllable, please).

The brew smells really good and has got down to SG1012. I would be truly humiliated to die of low-alcohol beer. It's one thing to go out in a blaze of glory, but quite another to snuff it from an excess of caution.
Recipe to follow if interested, when I find my notes... Cheers!

 

[foxy]

You will not get botulism, got more chance of botulism eating foil wrapped baked potatoes cold.

 

[peebee]

Eee, 'tis lovely these scare stories. The virus vaccine will turn us into monkeys, etc.. I'm jealous of the imaginations needed to invent these stories; I'm pretty good, but I'm not that good.

First; no-one has ever died of botulism from home-brewed beer: Check it, and then verify any you do find (people write all sorts of rubbish on the Internet and I'm certainly not behind all of it)! Next, as a brewer you spend loads of time and money to attempt to wipe out any bugs that might come in contact with your beer. Thirdly; yeast doesn't care to share its dinner with anything. One trick it uses is ensures the pH drops damn quick. Other bugs use the same trick, but the bug behind botulism doesn't and packs up at pH 4.6 and below. If you are going to leave your wort around for 3 days or more without pitching (the bug needs 3 days to create a fatal dose of toxins <EDIT: Where'd I dig this rubbish up from? Doesn't add up. I think I've just become victim of those people writing rubbish on the Internet ... anyone got a banana?>) then you are running a big risk ... not of suffering botulism, but of creating undrinkable beer.

 

[ryderkellan]

Thanks! Reassuring. I had an extra swing round the cage to celebrate. Now to see if it's drinkable!

 

[steve123]

I’d be interested to see your recipe once you find your notes

 

[chthon]

To wrap it up.

There is only a chance of botulism w.r.t. wort that is stored under anaerobic conditions. This mostly happens in two cases: no-chill cubes that have been left for more than three days, and wort stored in mason jars or cans, but not cooked above 121° C for at least three minutes. In the first case, most worts will be inoculated with yeast before three days are over. In the second case, this might pose a problem. This is the biggest cause of botulism: improper canning.

There are three parts of the botulinum problem:

• The bacteria spores. These are very heat resistant, but according to this document 25 minutes of boiling at 100°C does destroy them
• The bacteria themselves, which develop after three days out of the spores in a supporting environment
• The toxin secreted by the bacteria, which is dangerous in really small doses (0.1-1.0 µg)

Storing wort that has been boiled for an hour, and at boiling temperature in Mason jars (weck) should pose no problem.

Cooled wort that has been inoculated with yeast in less than 48 hours should pose no problem.

When fermenting, the yeast lowers the pH of the beer, thus again no problem.

Suppose wort has been boiled and stored no-chill for longer than three days, the safest way to handle it would be to boil it again for a quarter of an hour:

• Possible botulinum bacteria will be destroyed
• Possible toxins from the bacteria will be denatured

Of course, the wort will again need to be cooled.

 

[ryderkellan]

That's really helpful - thanks @chthon @peebee
And here's the recipe @steve123 . This was to use some NZ hops I was given a while back - an attempt to make a low-alcohol NZ bitter.

10L
1.7kg lager malt (including a bit of mild ale malt)
200g pale wheat malt
40g chocolate malt
6g Challenger 60 min (adjusted down because of funny things that happen with LA beer)
15g Wai-ti @45 degrees (should have been earlier, but too busy)
15g Motueka @45 degrees
Malt cold mashed overnight. I'm a bit down on final volume. OG1018. Yeast: Gervin.

Let's hope I end up with something drinkable!

 

[An Ankoù]

On one hectic US forum there's a load of stuff about the risk of botulism. Is this something I should be worried about?

While one shouldn't ignore a risk, no matter how remote, I would say the much greater and immediate risk is that of drowning. Have you ever tried getting p1ssed on anything less than 2% abv?
Titter ye not and don't say you haven't been warned.

 

[foxy]

To wrap it up.

There is only a chance of botulism w.r.t. wort that is stored under anaerobic conditions. This mostly happens in two cases: no-chill cubes that have been left for more than three days, and wort stored in mason jars or cans, but not cooked above 121° C for at least three minutes. In the first case, most worts will be inoculated with yeast before three days are over. In the second case, this might pose a problem. This is the biggest cause of botulism: improper canning.

There are three parts of the botulinum problem:

• The bacteria spores. These are very heat resistant, but according to this document 25 minutes of boiling at 100°C does destroy them
• The bacteria themselves, which develop after three days out of the spores in a supporting environment
• The toxin secreted by the bacteria, which is dangerous in really small doses (0.1-1.0 µg)

Storing wort that has been boiled for an hour, and at boiling temperature in Mason jars (weck) should pose no problem.

Cooled wort that has been inoculated with yeast in less than 48 hours should pose no problem.

When fermenting, the yeast lowers the pH of the beer, thus again no problem.

Suppose wort has been boiled and stored no-chill for longer than three days, the safest way to handle it would be to boil it again for a quarter of an hour:

• Possible botulinum bacteria will be destroyed
• Possible toxins from the bacteria will be denatured

Of course, the wort will again need to be cooled.

The key words there are 'a supporting environment' wort is a hostile environment for botulinum, three key things hops, pH and high sugar content. Cooling wort is a modern process in the history of brewing, even when wort was cooled naturally then stirred with a filthy stick as way of pitching yeast there wasn't any cause to fear botulism. This was even in the days when people would drink weak beer and cider in preference to the water which would make them ill.
Beware of internet scaremongering and Marshall Schott.

 

[Wynne]

The attached web article gives a balanced, scientific review of the hazhard and risk related to botulinum poisoning in brewing. A key protecting factor in normal, all-grain brewing is low pH and this needs to be checked when brewing low or no alcohol beers, particularly, if using no-chill wort cooling and storing wort more than a day or two before adding yeast.

http://suigenerisbrewing.com/index.php/2020/01/29/botulism-in-beer/

 

[foxy]

The attached web article gives a balanced, scientific review of the hazhard and risk related to botulinum poisoning in brewing. A key protecting factor in normal, all-grain brewing is low pH and this needs to be checked when brewing low or no alcohol beers, particularly, if using no-chill wort cooling and storing wort more than a day or two before adding yeast.

http://suigenerisbrewing.com/index.php/2020/01/29/botulism-in-beer/

For a well balanced scientific review, it failed to mention the sugar content and the alpha and beta acids from the hops in wort inhibiting botulinum.
Another thing to consider is would anyone wait 3 days before pitching the yeast?

 

[ryderkellan]

The key words there are 'a supporting environment' wort is a hostile environment for botulinum, three key things hops, pH and high sugar content. Cooling wort is a modern process in the history of brewing, even when wort was cooled naturally then stirred with a filthy stick as way of pitching yeast there wasn't any cause to fear botulism. This was even in the days when people would drink weak beer and cider in preference to the water which would make them ill.
Beware of internet scaremongering and Marshall Schott.

Thanks. All good stuff.

 

[Wynne]

For a well balanced scientific review, it failed to mention the sugar content and the alpha and beta acids from the hops in wort inhibiting botulinum.
Another thing to consider is would anyone wait 3 days before pitching the yeast?

@foxy the article does consider both sugar content:

“Botulism grows under a limited range of conditions: it needs a source of protein for growth, a pH above 5.0, a salt concentration below 5-10%, a sugar concentration below 30%, and an oxygen concentration below 1%.”

and hops:

“It is unclear whether hops inhibit growth of botulism, although inhibition has been observed with highly purified extracts.” and links a US patent that cites a number of scientific papers in support: US6251461B1 - Antimicrobial activity of hops extract against Clostridium botulinum, Clostridium difficile and Helicobacter pylori - Google Patents

Like you, I’m happy that normal homebrewing carries little risk from botulism but, personally, I wouldn’t prepare and store wort e.g. for yeast starters without putting it through heat treatment at >121C.

 

[ryderkellan]

Well, this brew is the foulest I have ever made. Overripe fruit aroma, putrescent. Effortlessly horrible. Hey no.

 

[peebee]

Ahh, that's poo i'nit, It's all those negative vibes you put about, 'bout botulism an'like. Bit like the weather; we've just been upgraded to "yellow warning for rain". Am I going to be worried? Na, not me, I'll just put on a brave fac... 'scuse me, I'm just off to tighten me flood gates.