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gonna make some wort to freeze, for starters

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Hoochin'Fool

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Plan is to make one gallon of 1.040 wort from some briess 2-row, split it into two 1 gallon jugs, and freeze. Do I need to add any hops? I've got some already opened packs I could use. Do I need to boil it for longer than a minute?
 
Canning in quart Mason jars in a pressure cooker is much easier / safer way.
No need to boil as pressure cooker sterilizes.
You risk bacterial contamination otherwise as you can only sanitize.
Add no hops, just add yeast nutrient.
 
Why would this be any different from making beer normally, as regards botulism? I am going to bring it to a short boil, then chill in the sink (while covered), just like every other wort I've ever made -- only difference, is this will get poured back into the clean plastic jug that the distilled water came in, and then frozen.
 
I guess I still don't see how freezing a half-gallon of wort would be in the "danger zone" any longer than when I have to wait a couple of hours for the full-batch of wort to be cool enough to add yeast to.

But that said, I can see frozen wort won't be that much of a time-saver, when it will need to be un-frozen and warmed to yeast pitching temps anyways. 🤔
 
Obviously, storage time is a factor. If the last of your frozen wort isn't used for a few months and there's an active botulism infection that isn't going away on its own, bad things could happen when you thaw it out and use it...

Cheers!
 
I guess I still don't see how freezing a half-gallon of wort would be in the "danger zone" any longer than when I have to wait a couple of hours for the full-batch of wort to be cool enough to add yeast to.
Because you're storing it before it's fermented. Fermented beer has a low enough pH to prevent the spores from germinating. Wort isn't acidic enough.
 
If the last of your frozen wort isn't used for a few months and there's an active botulism infection that isn't going away on its own, bad things could happen when you thaw it out and use it...
However... both the vegetative bacteria and the toxin can be destroyed by boiling. Only the spores are resistant. So if you boiled (and chilled) the starter wort again just before use it would be safe.
 
I routinely make fairly big batches (3-4 gallons) of concentrated all-grain starter wort. It gets boiled down for an hour or longer, to an OG between 1.095 and 1.115. That concentrate is then kept deep frozen in 48oz cottage cheese containers.

Upon use it's diluted to starter wort gravity (1.037) and boiled for 15-20 minutes. Then chilled in the sink with cold water.
 
Do I need to boil it for longer than a minute?
I would boil it for at least 10-15 minutes to thoroughly pasteurize it.

I then reboil (and chill) the (previously frozen) diluted stock right before use, [Rephrased] After adding water to dilute the (concentrated) stock to starter gravity I then reboil that batch (and chill it in the sink) right before use, for all security.
It may be overkill, nothing is going to grow in the frozen stock, and the very soft tap or RO water used for dilution is 100% potable.
 
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Is all that worth not simply using DME when you get the urge to breed some yeast? :oops:

I remain unconvinced that mashing barley to 1.040 gravity, bringing it just to a boil (which will take at least 20 minutes going from 150F to 212F on my crappy stove), and then rapidly chilling and then freezing for infinite weeks is any more botulistic than the mashing/brewing I do for all my other beers. But yeah, DME is cheaper than my time, at least when it's for a yeast-starter, as opposed to actual beer!

But with that said, making a "big starter" that way, isn't really going to be much quicker than doing a quick mash/chill/pitch yeast. :bigmug:
 
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I remain unconvinced that mashing barley to 1.040 gravity, bringing it just to a boil (which will take at least 20 minutes going from 150F to 212F on my crappy stove), and then rapidly chilling and then freezing for infinite weeks is any more botulistic than the mashing/brewing I do for all my other beers.
Food safety practices generally tend toward overkill. For very good reasons.
 
I remain unconvinced that mashing barley to 1.040 gravity, bringing it just to a boil (which will take at least 20 minutes going from 150F to 212F on my crappy stove), and then rapidly chilling and then freezing for infinite weeks is any more botulistic than the mashing/brewing I do for all my other beers. But yeah, DME is cheaper than my time, at least when it's for a yeast-starter, as opposed to actual beer!

But with that said, making a "big starter" that way, isn't really going to be much quicker than doing a quick mash/chill/pitch yeast. :bigmug:
The Clostridium bacteria/spore is inactive at cold temperatures, so yes - you are fine leaving it frozen.

Thawing out a big chunk of wort is probably going to take some time though.
 
Thawing out a big chunk of wort is probably going to take some time though.
Yeah, that's a bit of a drawback. Even more so when stored in a milk jug, it all has to be melted inside the container to get it out.

I therefore really like my frozen concentrated starter wort stored in slightly conical containers. Once the outer edge has melted (by putting it in a pot with some hot or boiling water), it slides out.

I make many starters. and it's as easy to make starters from that as it is from DME.
 
When I grow up yeast for a batch, I generally will make up new. The canning process does produce break in the jar that I don’t care for. It’s my easy backup to keep everything going. I’m not into freezing and wondering and leaving anything to chance. To each their own, just how I personally roll.
 
I remain unconvinced that mashing barley to 1.040 gravity, bringing it just to a boil (which will take at least 20 minutes going from 150F to 212F on my crappy stove), and then rapidly chilling and then freezing for infinite weeks is any more botulistic than the mashing/brewing I do for all my other beers. But yeah, DME is cheaper than my time, at least when it's for a yeast-starter, as opposed to actual beer!

But with that said, making a "big starter" that way, isn't really going to be much quicker than doing a quick mash/chill/pitch yeast. :bigmug:
It takes 10 minutes at boiling to destroy botulism toxin. Longer for temps between 185F and 212F, with 185 being the minimum to destroy the toxin. The spores are more heat resistant and require a temperature at the 240-250F range to kill the spore. The spores are common everywhere. Just to a boil is not 10 minutes. How long you are at 185 until you take it off would indicate whether you potentially have destroyed any growth and toxin but 20 minutes may not be long enough. I water bath can pickles and you can use 180F for 30 minutes as a comparison. That is specifically for pickles however. They run specific experiments for canning times and these do vary by product. I lean towards your 20 minutes not being sufficient.

Wort usually ranges upwards from 5 as far as ph. Growth and toxin formation are inhibited at a ph of 4.6 and less. Beer itself ranges from 4.1-4.5. We aren't sterilizing with beer, we are sanitizing. The idea is to have a sanitized environment (boiled wort) into which a healthy and large population of yeast is added such that the yeast can outcompete other microorganisms and then create an environment more suitable for the yeast. The drop in pH from yeast activity is what then stops the growth and toxin formation of the botulism spores. Now as far as how much of a head start the yeast are getting, it would be best if all botulism growth and toxin were completely knocked out with the proper amount of time between 185-212F. Also important is minimizing time between cooling below 185 and pitching, since any spores aren't destroyed in the wort.
 
Also important is minimizing time between cooling below 185 and pitching, since any spores aren't destroyed in the wort.
This is true. However, the spores will not germinate under aerobic conditions and the wort shouldn't become anaerobic until the yeast get to work and use up the oxygen. I assume this is why no chill brewers aren't all dead. I guess this would also mean that it would be a bad idea to combine hot side LoDO with no chill, but who would do that anyway?
 
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This is true. However, the spores will not germinate under aerobic conditions and the wort shouldn't become anaerobic until the yeast get to work and use up the oxygen. I assume this is why no chill brewers aren't all dead. I guess this would also mean that it would be a bad idea to combine hot side LoDo with no chill, but who would do that anyway?
Yes anaerobic is also a condition although low-oxygen is also used. As the temperature is increased to a boil oxygen is released. I haven't delved into the LODO discussion beyond closed transfers however. The measureable level of oxygen would be the imporant value, aerobic and anaerobic are just two categorical measurements. I don't know if the amounts of oxygen that might be present are sufficent to inhibit growth or not. Blasting it with O2 for instance might be all that is needed. I think with healthy and comparatively large numbers of yeast cells it is most likely it will get outcompeted anyway but I wouldn't want to say that without actual data. Low sugar and salt also are mentioned as being beneficial to its growth. I don't have any numbers for those either. It generally takes a few deviations from good practice to accidentally kill someone with botulism from foods.
 
I'm with @Dog House Brew in the pressure canned wort camp. Mostly because I have waaaaay more shelf space than freezer space and more jars than common sense.

What @Hoochin'Fool is proposing is no different than making some soup and freezing the extra. It'll be fine.
Weeelll context matters.

Was the soup commercially canned and you put the leftovers in the freezer immediately, than boiled again on the stove for say 10 minutes. Or did the soup sit on the stovetop and let cool then frozen?

Did you make the soup from scratch? Then did you bring it to a potluck an hour away, bringing the leftovers home to be frozen then reheated in the microwave or just get it hot on the stove? Was it someone else's soup at the potluck that you brought home? Was it their canned soup they brought? Does that sweet church lady own a pressure canner? Again it's very rare, I've looked into cases before as far as canning and potlucks and gatherings were situations where botulism poisoning has occurred. I did not read about any related to beer. There are different scenarios too for getting botulism but I can only remember one that was different from food and it was infant botulism. I'm more emphasizing breaking the chain of a series of small mistakes, intentional or not, to prevent serious consequences. This applies to other safety situations as well. Like how not to die out in nature.
 
A major problem is that no research has been done on "wort canning". All recipes we see on the interwebs are just spit-balling. Sure, 15 minutes at 15psi "seems" reasonable, but it's just a guess.

I sent the following query to the National Center for Home Food Preservation in Georgia:
There are a number of "Internet recipes" for preserving a sweet liquid used to make beer yeast starter, known as "wort". This liquid is usually made by adding water to dried malt extract. The resulting liquid can have various concentrations of sugar, and in general would be considered low-acid.

Most recipes arbitrarily call for a 15 minute process at 15 psi in a pressure canner. I cannot find documentation confirming 15 minutes is a valid time. Can you help to clarify the proper processing time?

The response received was:
We do not know of any research validating the safety of canning a malt extract solution is there any information on determining a safe processing time. Processing times are not something that can be estimated so we cannot recommend canning a product such as this as safety cannot be ensured.


Thank you for your interest in the National Center for Home Food Preservation.

National Center for Home Food Preservation Team
Cooperative Extension
University of Georgia

(Any aspiring brewers working for the NIH or Ag Dept or microbiology lab at a university who want to do the work?)

The lack of an established procedure is a not-insignificant problem, IMO. If you look at pressure canner "recipes" for chicken, beef, and vegetable stocks, processing times (for quarts) range from 15 to 50 minutes. Not to mention altitude adjustments (though above 1000ft, it's a good idea to use 15psi). Head-space requirements seem to be consistent at one-inch head-space. Pressure, jar volume, concentration, pH, time, altitude, head-space--they all count and must be accounted for!

I use 25 minutes at 15psi in quarts, using a 1-inch head space, at 4682' above sea level, with 1.030-1.040 wort. And I don't keep it stored for more than a couple of months, and I always check my seals.

I would simply exercise caution in performing pressure canning on wort (and, no the Instant Pot or your wife's hot water caner WILL NOT be sufficient to pressure-can ANYTHING--Use a true Pressure Canner!)

C. botulinum is no joke.
 
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