New BYO Aussi brewing article

[Laughing_Gnome_Invisible]

This is actually a very interesting thread once you navigate all the OT chatter and the feud between remilard and Revvy.

I'll admit- botulism toxin scares the bejeezus out of me, and the technique being discussed here makes me very uneasy.

I don't see myself trying it.

Perhaps a mod (A new one even) could tidy it all up?

 

[Madman]

There has to be one microbiologist out there that brews and can weigh in on this. I'm comforted enough by the Aussies, Palmer, and the Pratt quote, but I'd like to hear something authoritative from an expert on bacteria as well.

Hrm, is "authoritative" right, sheckster?

 

[remilard]

There has to be one microbiologist out there that brews and can weigh in on this. I'm comforted enough by the Aussies, Palmer, and the Pratt quote, but I'd like to hear something authoritative from an expert on bacteria as well.

Hrm, is "authoritative" right, sheckster?

The Pratt quote cannot be interpreted as saying that botulism cannot grow in wort since Pratt, in fact, said just the opposite.

 

[flyangler18]

Perhaps a mod (A new one even) could tidy it all up?

A splendid idea!

One more comment regard this 'cubing' technique. I'm not particularly well-versed (or at all!) in microbiology, but I know that both time and temperature are the largest factors regarding microbial growth. Allowing a volume of 5 gallons of near-boiling wort to cool to ambient must take an excruciatingly inordinate amount of time, creating what to is, to my mind, a big honkin' petri dish. If the bacteria responsible for causing botulism is as ubiquitous as an earlier post in this thread indicates, then certainly some must be present in the cubed wort (especially since the spores withstand boiling). I'd very curious to know if Saccharomyces is able to consume botulism toxin; that may quell our fears about this method.

It's clear that it seems to be working for our brewing brethren down under. Having spent some time in that country, I can speak to their ingenuity in just about everything!

 

[remilard]

Well, food is canned improperly all the time and only a few dozen people a year die from food borne botulism.

Given how much more popular canning is world wide than no chill home brewing, you would expect perhaps very close to zero (but not exactly zero) cases a year of food borne botulism from brewing, even if the risk were roughly comparable to improper canning.

I think that anecdotal evidence is worthless in this (and most) cases. All the anecdotal evidence proves is that it is very likely that you won't kill yourself. It certainly does not prove that it is impossible.

I seem to recall Dan Gordon having a very negative reaction to this technique. While not a microbiologist, he is possibly the most technically trained brewer in the US. The problem with asking a microbiologist is that they may not know enough about the properties of wort to give a confident answer.

Someone working at a yeast supplier is probably the best authority available given that they can be reached, have very good knowledge of microbiology, and have very good knowledge of the properties of wort.

 

[Madman]

The Pratt quote cannot be interpreted as saying that botulism cannot grow in wort since Pratt, in fact, said just the opposite.

Oh, Botulism specifically... did you know that this is an anaerobic pathogen? It's toxin is one of the few that is broken down by boiling. Did you know tht it is strongly inhibited by isomerized alpha acids, even in water? Since fresh wort has a healthy amount of oxygen in it, the beastie cannot even get started, then once the O2 is used up, it doesn't have a chance against the hops or the yeast.

It seems to me that he's saying that the botulism will die in a boil, but does stand a very very slight chance in cool wort (strongly inhibited). However, he goes on to say that whatever tiny amount may have grown in the cooled wort can't compete with the yeasties.

So, you are right to a point, but he's still saying that despite that, it's not a problem.

 

[remilard]

It seems to me that he's saying that the botulism will die in a boil, but does stand a very very slight chance in cool wort (strongly inhibited). However, he goes on to say that whatever tiny amount may have grown in the cooled wort can't compete with the yeasties.

So, you are right to a point, but he's still saying that despite that, it's not a problem.

Well, he is making a mistake in terminology.

Botulism is a disease caused by botulin toxin. Botulin toxin is produced by C. Botulinum, which is a spore forming bacteria.

Now, C. Botulinum will be killed by prolonged boiling such as in the typical production of wort. Also, any existing botulin toxin would be denatured as well and would be no longer harmful. Pratt is quite right about that.

However, C. Botulinum spores are not killed by boiling. In normal beer production this is of no concern at all because the fermenting beer will be an environment hostile to C. Botulinum and soon the pH of of the beer will be too low for it to grow and produce any toxin.

The potential problem with no chill methods, especially if the wort is stored longer than necessary to chill which seems to be the case, is that C. Botulinum probably can grow in wort (wort meets all of the stated criteria). Hot packing the wort as in no chill will create the required anaerobic environment (note that immediately chilling and oxygenating the wort would create an aerobic environment hostile to C. Botulinum), the pH is right in the state range for C. Botulinum growth, there is plenty of nutrient.

I disagree with nothing Pratt said and later in the same thread the above quote came from, he clarified that his comments were about beer, not stored wort.

Read it in context for yourself.

Beer and Homebrew Forums - Brew-Monkey.Com - Foodpoisoning

 

[Parker36]

AM I the only one here that thinks botulism is really cool? The mechanism it works by is rather ingenious actually. It enters the pre synaptic terminal of nerve cells and cleaves the SNARE complex all of which essentially act as an acetylcholine inhibitor. Very cool.

 

[Madman]

Then, the real question is this: after the boil and if botulism makes it into the wort, will the inhibited bacteria have the time to thrive and create enough botulin to be toxic? This is where a microbiologist would come in handy, because I would like to know how much the AA inhibit the bacteria, how many ppm it would take for botulin to become toxic, how fast the bacteria grows, how how fast it makes the botulin.

 

[Madman]

And, yes, that's very cool, Parker

 

[flyangler18]

Then, the real question is this: after the boil and if botulism makes it into the wort, will the inhibited bacteria have the time to thrive and create enough botulin to be toxic? This is where a microbiologist would come in handy, because I would like to know how much the AA inhibit the bacteria, how many ppm it would take for botulin to become toxic, how fast the bacteria grows, how how fast it makes the botulin.

I'd say this would be a perfect opportunity to email White Labs and Wyeast for their professional opinions. I'm not well-versed enough in the terminology to compose one that hits all the major points.

 

[remilard]

1 microgram of botulin is toxic to humans.

The hop question is interesting. Pratt is light on specifics and the internet doesn't seem to fill that gap.

A couple of thoughts.

Generally the anti-microbial properties of hops are due primarily to beta acids, not alpha acids. Not that this is of any practical importance if hops and not some extract are used.

Beta acids in hops are anti-fungal as well as anti-bacterial, however yeast does pretty well in hopped wort. Clearly the presence of hops is not biocidal so I think it would be wise to discount the notion that hopping wort will prevent C. Botulinum growth unless the magnitude of the effect can be quantified.

 

[Fatgodzilla]

Crikey .. some of you blokes are really thick, aren't you. Rabbiting on about botulism as if you know anything about it. Now I don't know anything about it much either. I just go on the fact that thousands and thousands of brews have been made using the no chill method and no one I know of has died.

We have commercial no chill cubes of wort for sale in Australia and I assume you have them also in the USA and Great Britain. Google "Fresh Wort Kit" if you don't believe me. Maybe wort kits are an Australian thing too, because I couldn't find any overseas references (but I didn't look hard). Anyways, with a number of commercial breweries making and selling these wort kits to the public here in Australia, I'm sure they are subject to strict health regulations which would mean that if there was a botulism chance, they wouldn't be on sale. Homebrewers are using exactly the same techniques. No problems.

Like BIAB, no chill cubing is a personal choice. Either do it or don't. If you want to use your chiller systems, go for it. If however you want to try this method, go for it.

Simple advice. Do your research. If you have a question, PM me. I'll send you some info from Aussie brew sites. I'm sure YouTube has some demos on file. But please, no more bull**** about botulism and how you you won't respect this method because of it. Gotta warn you Americans the world is not flat and there is life beyond your borders.

Cheers

 

[Fatgodzilla]

Cut and pasted this from the AussieHomeBrewer site. It'll give you some ideas on the matter, discussions we have had about it here and some methodology. Hope this helps.

You will find a lot of posts on this forum mentioning the "no-chill" method and also the use of a cube. There isn't really any great mystery about the no-chill method and it can be utilised easily, cheaply and with excellent results.

Traditionally there has been a school of thought that suggests; that after boiling wort it must be cooled quickly to promote the formation of cold break and allow for the pitching of yeast ASAP. As a result there are a plethora of weird and wonderful chillers out there to allow you to chill your wort quickly and effectively.

Another school of though has recently gained momentum which promotes the use of cube to effectively "hot-pack" the wort post boiling, thereby allowing it to cool over an extended period of time eg overnight.

I will try and explain, to the best of my ability, what this method involves, possible problems and important points to consider in its use. I'll start at the beginning...

What is a Cube?

This is a common question one sees on beer forums. Essentially it is a food grade sealable plastic water container or jerry can made of the same material as a fermenter. A picture is worth a thousand words, so...



They are available in a range of sizes eg 15L, 20L, 25L from camping / hardware stores and typically range from $10 to $15.

Also worth mentioning is that, for example a 20L cube will actually hold 23 odd litres.

OK I've Got A Cube, Now What?

Essentially the method involves the following:

- You make your wort as you normally would.
- After flameout and whirlpooling, and with appropriate hosing, drain the still near boiling wort into a plastic cube, trying to avoiding splashing.
- Once you have drained the kettle into the cube, squeeze as much of the air out of the cube as you can and seal it with the lid.
- Put the cube on its side for 10 minutes or so to allow the hot wort to come into contact with handle and lid.
- Leave the hot cube to cool overnight (upright) or however long it takes to arrive at pitching temperatures.
- Pour the contents of the cube into a fermenter, splashing as much as possible to assist in aeration and pitch yeast as you would normally.

That's the crux of it!

Sanitising

Cleanliness with this method as with all aspects of brewing is essential.

Before using the cube ensure that it is clean and sanitised. My personal regime sees me storing cubes (when not in use) with a couple of litres of bleach solution in them. I occasionally give the cube a shake when passing to cover the cube walls. On brew day I clean out the bleach solution and give it a shot with idophor to sanitise. I always clean out the cube thoroughly immediately after use. There are many ways to clean the cube - use what works for you in other aspects of your brewing.

The hose used for transferring the hot wort must also be cleaned. Typically I connect the hose to the kettle during the later parts of the boil and recirculate boiling wort through it and the ball valve to flush out any nasties. The end of the hose that goes into the cube gets put into the boiling wort during the boil to sanitise. Again do what works for you to ensure everything is sanitary.

Storability (Extended Storage)

Cubes that have been properly packed may be stored for extended periods. Some users have reported good results with cubes being stored for over a year. Personally I have stored cubes for 1 to 2 months without issue.

Getting The Air Out / Squeezing The Cube

It is suggested that most if not all of the air in a cube should be expelled when sealing. However occasionally it may be impossible to do so. I have not encountered any ill effects from not expelling all the air. But as a general rule, if I intend to store a cube for over a week I ensure that most of the air has been expelled or use a smaller cube.

Benefits

No-chilling has a series of benefits including
- minimal outlay (no chiller required to make all grain beer, only a cube)
- minimal time required (the time usually allocated to chill the wort is avoided on brew day)
- minimal water required (ie sanitisation only)
- storability of the wort for extended periods (wort production does not have to coincide with yeast starter preparation)
- ability to make wort in bulk and store for later fermentation
- portability of wort in the cube

Making Higher Gravity Wort (Dilution at Fermentation Time)

An option with this method is take wort of a higher gravity eg 17 litres of 1.060 SG wort can be diluted with 3 litres to give 20 litres of 1.051 SG wort. This allows you to use cubes of a smaller capacity and make double batches ie two cubes of wort without having the capacity of doing a full final volume boil.

Dry Hopping In The Cube (Cube Hopping)

No-chilling allows hops to be added to the cube before the hot wort is transferred into it. There is some discussion about the possibility of doing away with the normal aroma / late addition and replacing it with cube hopping - effectively allowing more of the hop aroma to be trapped within the cube. I am not aware of any definitive examination of this however but have dry hopped in the cube for extra hoppiness.

Can I Replace the Cube's Bung With A Tap?

I have put taps on a couple of my cubes and have not had a problem. They do make it easier when transferring wort to the fermenter. I find it a bit of a challange sometimes, when trying to tip a full cube into a fermenter, to get the wort in without spilling any.

What If My Cube Starts to Swell?

You will find that as a cube cools its sides begin to get sucked in (essentially cooled wort is about 4% smaller (volume wise) than hot/boiling wort). This is nothing to be concerned about.

However should the cube begin to swell after it has cooled this may be an indication of an infection. What you do in this scenario is your choice. You can discard the wort or ferment it to see how it turns out.

I have never had a cube swell / be infected in over 20 batches. Some users report the same for 100 plus batches.

Caveats

- Ensure the cube and hose are sanitary.
- Do not be tempted to cool the cube prematurely by putting it into a swimming pool or other body of water. Rapidly cooled hot packed wort can give rise to infections as it does not allow for the cube to be exposed to the hot wort for long enough to ensure that any bacteria in the cube is killed.
- Remember to place the cube on its side after packing to expose the handle and cap directly to the hot wort.

No-Chill Critics

Some research into the no-chill method will bring up some criticism of the method. Arguments against include
- Beer haziness
- Problems with long term beer stability
- Loss of hop aroma
- Increased bitterness
- Leeching plastic
- DMS production
- And in the extreme the risk of botulism (a deadly anaerobic bacteria)

I have not encountered any of these problems in the beer I have made nor have members of the Illawarra Brewers Union who employ the method almost exclusively.

Other Remarks

The no-chill method is advantageous to the brewer as it allows him/her to do away with a chiller (which can be expensive and consume water / resources / time). It basically allows the novice brewer to cross over to all grain brewing (the dark side) much more easily. Further other advantages are to be found in storability of bulk wort and being able to control when you ferment the wort.

Before discounting the method give it a go to see if you find any of the benefits to be had in no-chilling exist for your brewing.

Cheers

 

[Revvy]

Actually, Fatgodzilla, that's the issue...this is totally new to most of us...it was jusr written up for the first time (that I know of) in the latest BYO...

Hence all the discussion..it's really unknown territory to us in the states...But I've been reading and listening to some of the stuff from your side of the world, even lurking on Aussie homebrewer a time or two, and I've been impressed with some of the stuff you guys do...

Methinks the fact the we had prohibition might have had something to do with the fact that in many ways you are ahead of us in inventedness....but who knows.

Thanks for the info!

 

[Parker36]

Few things:

1) Madman: The boiling should destroy any toxins (from what I've read, haven't seen any read scientific evidence of it, sorry) and should kill the bacteria. Also, it is not the actual bacteria that is being inhibited. The bacteria creates the toxin and is not affected by it. The problems occurs when the toxin (Botulinum toxin) enters human (or other mammal cells) and interferes with the communication in neuro-muscular junctions (which is carried out by the acetylcholine).

2) Flyangler: I'll work on asking White Labs about it (they are the local yeast guys for me - just across town)

3) remmy: Any potential C. botulinum would be killed by the boil. Give me a few minutes and I'll explain how the the hops interact with both yeast cells and with various undesirable bacteria, I just need to find some sources to double check some things.

4) fatgodzailla: We really don't have those premade worts (or at least I haven't seen them) so it is all pretty new to us over here

 

[Revvy]

4) fatgodzailla: We really don't have those premade worts (or at least I haven't seen them) so it is all pretty new to us over here

Parker, there is at least ONE premade no boil wort product out here now..I know there's even a thread about it on here, though the name escapes me..But it's in like a 3 liter pop bottle with an airlock...and all you do is pitch the yeast...

 

[Madman]

Few things:

1) Madman: The boiling should destroy any toxins (from what I've read, haven't seen any read scientific evidence of it, sorry) and should kill the bacteria. Also, it is not the actual bacteria that is being inhibited. The bacteria creates the toxin and is not affected by it. The problems occurs when the toxin (Botulinum toxin) enters human (or other mammal cells) and interferes with the communication in neuro-muscular junctions (which is carried out by the acetylcholine).e

Yeah, the boil will definitely kill the bacteria and destroy the toxin. What I'm curious about is the remote possibility of bacterial spores being introduced after the boil and before packaging. The toxin is actually produced as the spores mature, which could happen in the cool stored wort.

I have to be honest, it seems to me that the chances are so remote as to not cause any anxiety. The questions for me are academic at this point.

 

[Parker36]

Parker, there is at least ONE premade no boil wort product out here now..I know there's even a thread about it on here, though the name escapes me..But it's in like a 3 liter pop bottle with an airlock...and all you do is pitch the yeast...

They might be out there, I guess its one of those things I didn't even know existed so didn't bother looking.

Now, back to remmy's question about how hops affect different yeasts and bacteria. The way the acids work in inhibiting various cells is by coating their membrane's and reduces the viability. It works exactly the same for yeast cells as well with undesirable bacteria cells. The major difference is that your cell pitch count for yeast should be so high that any effect that the hops have on the cells will be outdone by the sheer number of yeast cells - this is why you don't hop starters. On the reverse side, using the Aussie method, if you did have any C. botulinum cells, they should be so low in number that between the hops coating their membranes, acidity and the yeasts just out competing them not too mention abundance of )2 in the wort (and then beer) they should be destroyed/neutralized.

Bottom line. Is botulism possible brewing with this method? Of course. Is it any more likely than brewing with out standard cooling/pitching of the yeast? No, not significantly at least. Either way the possible is extremely remote and even if you do have infection rates high enough to produce the toxin in quantities large enough to cause bodily harm, it is more likely due to your sanitation process than using this particular method

 

[Danek]

I can see why you'd want to get rid of the need to use a chiller if you're living in a country where water is a relatively precious resource. For that situation, I think the no-chill method is a truly ingenious idea. But is there any real advantage to no-chilling it in the US or UK, other than a very rare situation where you make a wort but (for some reason) don't want to pitch it?

 

[remilard]

3) remmy: Any potential C. botulinum would be killed by the boil. Give me a few minutes and I'll explain how the the hops interact with both yeast cells and with various undesirable bacteria, I just need to find some sources to double check some things.

Yes, I have said myself that the bacteria are killed by boiling. The spores are not.

I understand the mechanism by which hops are anti-fungal and anti-bacterial, however this whole argument that hops will prevent C. Botulinum from growing in wort is extremely hand wavy.

 

[Parker36]

Yes, I have said myself that the bacteria are killed by boiling. The spores are not.

It is true that most companies that package botulism vulnerable food (such as canned green beans, the most common culprit) heat at temperatures around 120C (~250F), it is more because they do not want to cook the edible food rather than because it is the minimum temperature to kill the bacteria. They only heat the produce for between 2-3 minutes at this temperature, then rapidly cool to keep it "fresh". Added to this fact is that the our wort is much more acidic than the environment found in canned foods (which just happen to be right in its wheel house). Thus we can conclude that our boiling (between 200 and 212F depending on you altitude) for 1 hour + is sufficient to destroy most of (if not all) spores from the potentially dangerous bacteria. I suggest reading up

for more information if you are still not convinced that our friends from down under's methods are less safe than our own

 

[BierMuncher]

Perhaps a mod (A new one even) could tidy it all up?

Done.

OT posts deleted.

OT lines edited out of otherwise useful posts.

This topic has value. Let's keep it that way.

Now I'm late for my Chimay Blue waiting for me. You happy?

 

[remilard]

I would love to read up about botulism spores being reliably destroyed by one hour exposure to 100 C and pH of about 5.2. Please list references here.

 

[remilard]

I would think the mere existence of the Tyndallization procedure indicates that hour long bouts of boiling at atmospheric pressure are not sufficient to kill spores.

Tyndallization involves boiling, waiting for spores to germinate, boiling again, rinse repeat.

 

[Kaiser]

Fatgodzilla,

Sorry if our discussion of this subject offended you. Let me tell you that there was no intention to discredit the no-chill method. The no-chill method is certainly new to us and it seems that it has been used down under much more extensively including the sale of commercial fresh wort.

My intentions are not to banish this method but understand it more fully. From what I know there should be the same risk as canning low acid foods but based on your accounts there is not. So I'd like to expand my knowledge about canning low acid foods.

That's why I brought up the botulism thing and would like this discussion to continue.

If it is ok to keep wort in a cube for an extended time, would it also be ok to can hopped starter wort without a pressure cooker?

Kai

 

[remilard]

Not much info on botulism and wort on the internet other than forum posts. I would guess that wort is never hot packed and then not boiled again in any kind of commercial venture, which may explain the lack of interest in the topic.

Nate Sampson, who I believe is a microbiologist, believes that botulin toxin in hot packed wort is possible but would be extremely rare (as it is in food).

TastyBrew.com | Forum | canned wort/Botulism

 

[Fatgodzilla]

Fatgodzilla, Sorry if our discussion of this subject offended you...

Far from offended Kai. I've got extremely thick skin that goes with the thick head. Australians play sport not for fun but to sledge .. we are a weird mob after all. I was expressing my amazement at the depth of the discussion into botulism and how far removed from reality I perceive the threads to be and the Off Topic side bar conversations going on.

In Australian discussions I haven't seen any debate on botulism. We were more concerned about cold breaks, chill haze etc. We just assumed that botulism was not an issue. Aeration is an issue, infection from poor sanitation is an issue. Botulism .. not an issue. You have more chance of botulism as an kit & kilo brewer - add can goo, add sugar, add water, wait till cool then add yeast. Can't see anyone raising that possibility yet.

Let me tell you that there was no intention to discredit the no-chill method. The no-chill method is certainly new to us and it seems that it has been used down under much more extensively including the sale of commercial fresh wort.

Again, a little amazed that America hasn't got fresh wort kits - business opportunity ? Seems UK also in same boat, though an excuse offered is the number of pubs in UK so close to population base.

My intentions are not to banish this method but understand it more fully. From what I know there should be the same risk as canning low acid foods but based on your accounts there is not. So I'd like to expand my knowledge about canning low acid foods.That's why I brought up the botulism thing and would like this discussion to continue.

I hope you read the article I cut/pasted from AHB source - the author is a mate and this offers a simple but concise explanation of the process.

There should be a similiar risk of botulism in canning wort extract - read tins of Coopers, as to the no chill of wort. After all, extract is wort that has been evaporated to remove water. Nothing else differs. The extract is not cooked in the can, as a number of food products are; it is stored in the can. The only logical difference I see is that there will be slightly more air stored in a cube and that the canning line will probably have better sanitary process when compared to a home brewer's shed. To the best of knowledge, no one has ever mentioned botulism and cans of extract.

If it is ok to keep wort in a cube for an extended time, would it also be ok to can hopped starter wort without a pressure cooker?

I assume this is you talking about what I said above .. it's the terminology I can't really decipher. As I see it, the contents of Coopers cans are not pressure cooked. I'll email Coopers directly and see if I can get an answer about how the wort is canned and specifically mention botulism concerns. We'll see what they say.


Cheers

 

[Parker36]

I would love to read up about botulism spores being reliably destroyed by one hour exposure to 100 C and pH of about 5.2. Please list references here.

Sorry, thought I had linked to it. Here are two very interesting articles that should help you understand the topic:

International Handbook of Foodborne ... - Google Book Search

ScienceDirect Login

 

[chefmike]

I knew my old ServSafe class would come i handy.

the spores have problems going vegetative in sugar solutions, which would be the case in a wort. I do not have a source for exact concentrations/gravities... It is a weird quirk that I do not understand, but it is related to why you do not feed babies honey. When the sugar solution has the bacteria in it, it can only harm an infant eating it due to the non acidic nature of an infants digestive track.

I pulled the following from the wiki (my only source at the moment): "Growth of the bacterium can be prevented by high acidity, high ratio of dissolved sugar, high levels of oxygen, very low levels of moisture or storage at temperatures below 38°F (type A). For example in a low acid, canned vegetable such as green beans that are not heated hot enough to kill the spores (i.e., a pressurized environment) may provide an oxygen free medium for the spores to grow and produce the toxin. On the other hand, pickles are sufficiently acidic to prevent growth; even if the spores are present, they pose no danger to the consumer. Honey, corn syrup, and other sweeteners may contain spores but the spores cannot grow in a highly concentrated sugar solution; however, when a sweetener is diluted in the low oxygen, low acid digestive system of an infant, the spores can grow and produce toxin. As soon as infants begin eating solid food, the digestive juices become too acidic for the bacterium to grow."

Fascinating thread... I have been reading a ton over on the aussie boards...
Corny Instead Of A No-chill Cube..... - AussieHomeBrewer.com

They discuss this technique with cubes, in brew kettles and the thread above, in cornies!