Storing Sterile Wort

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MoronBrothersBrewery

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I've heard of people keeping some sterile wort around for yeast starters, especially if you're stepping them up, and I'm curious about the process. Can you use sterile mason jars, keep in the fridge, and when ready to use, just pour? Do you need to freeze? How long will it last? What are some of the benefits of keeping sterile wort?

Thanks!
 
I just put it in 1 qt plastic sports drink bottles and freeze it. Boil it for a few minutes to re-sterilize before you use it.
 
I often make a quart or two of wort after sparging. It's usually around 1.020, so I boil it down more if I want a 1.040 starter or just boil it for a few minutes it if I'm looking for wort to step up dregs. I put them in sterile mason jars - put some water in them and boil it in the microwave for a few minutes to sterilize & StarSan the lids - and then store them in the fridge since I don't pressure can them afterward. I reboil them some times if they've been in the fridge for a while just for piece of mind.
 
I often make a quart or two of wort after sparging. It's usually around 1.020, so I boil it down more if I want a 1.040 starter or just boil it for a few minutes it if I'm looking for wort to step up dregs. I put them in sterile mason jars - put some water in them and boil it in the microwave for a few minutes to sterilize & StarSan the lids - and then store them in the fridge since I don't pressure can them afterward. I reboil them some times if they've been in the fridge for a while just for piece of mind.

Boiling does not ensure it is sterile. You need higher temps than 212. Hence, pressure canning.
 
Boiling does not ensure it is sterile. You need higher temps than 212. Hence, pressure canning.

I believe it needs to be at 250F for 5mins to kill botulism spores. That means it needs to be held at 15PSI to reach that temp. I'm going from memory here so don't crucify me too badly if I'm wrong.

My process is to add measured amounts of DME and Yeast Nutrient to a mason jar, then add filtered water, then I pressure can at 15PSI for 15-20mins. Sometimes I'll also can the 2nd runnings from a mash but not too often.
 
Boiling does not ensure it is sterile. You need higher temps than 212. Hence, pressure canning.

True, although I've never had a problem with just boiling for a few minutes. I also don't keep boiled wort in the fridge too long because I know there is a small chance of contamination. The large amount of yeast in a small amount of starter wort also keeps the nasties at bay.
 
This is what I intend on doing if I ever get a frigging pressure canner. I've been putting it off forever. Looking for a big one on craigslist.

For the money THIS one on Amazon is what I'll go with when I purchase another one. I can only fit 2 quart jars in my current one.

True, although I've never had a problem with just boiling for a few minutes. I also don't keep boiled wort in the fridge too long because I know there is a small chance of contamination. The large amount of yeast in a small amount of starter wort also keeps the nasties at bay.

I don't see contamination a real issue in this scenario, the possible issue is the toxins created by the Botulism Spores as they grow. It's a health issue that necessitates canning your wort, not a possible infection issue. Once fermentation begins the botulism spores cannot do their thing in an anaerobic environment so it's a non issue at that point. BUT if they've already pushed those toxins in to the wort...

I guess it's all a calculated risk, for all I know the toxins can't survive fermentation but I'd rather be safe and can my wort.
 
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I pressure can my starter wort, but someone posted a while back that boiling temperatures will neutralize the toxins produced by botulism. I would want to at least boil the wort prior to putting it in mason jars if pressure canning is not an option.

I run a 3.5 gallon no sparge to make the starter wort, so I might as well pressure can it if it needs to be boiled anyway. Not a big difference in effort, but more time is required for the canning process. Mostly the cool down part. I bought a 23 qt Presto canner which will do 7 quart jars at a time. These can be had for about $50 or so if you shop around.
 
From Wikipedia:

Botulin toxin produced by C. botulinum is often believed to be a potential bioweapon as it is so potent that it takes about 75 nanograms to kill a person (LD50 of 1 ng/kg,[23] assuming an average person weighs ~75 kg); 500 grams of it would be enough to kill half of the entire human population.

Clostridium botulinum is a soil bacterium. The spores can survive in most environments and are very hard to kill. They can survive the temperature of boiling water at sea level, thus many foods are canned with a pressurized boil that achieves an even higher temperature, sufficient to kill the spores.

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 3°C (38°F) for 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.
 
From the CDC:

Despite its extreme potency, botulinum toxin is easily destroyed. Heating to an internal temperature of 85°C for at least 5 minutes will decontaminate affected food or drink.

So it looks like re-boiling (Going over 185F) for 5 mins will certainly make the wort safe for consumption by destroying the toxins produced by the spores.
 
From the CDC:



So it looks like re-boiling (Going over 185F) for 5 mins will certainly make the wort safe for consumption by destroying the toxins produced by the spores.

Right. Regardless of how the wort was stored, as long as it is boiled just before use the toxins are taken care of. We don't care about the spores as they aren't an issue (and surround us all the time anyway).

Funny, I think this exact thread comes up every few months (usually with more arguing, but with the same result).

Thanks wyzazz for getting those pieces of info.
 
Right. Regardless of how the wort was stored, as long as it is boiled just before use the toxins are taken care of. We don't care about the spores as they aren't an issue (and surround us all the time anyway).

Funny, I think this exact thread comes up every few months (usually with more arguing, but with the same result).

Thanks wyzazz for getting those pieces of info.

I know I've seen it before in multiple places, and again with more arguing. I'm not one for arguing much, in the end I just want to make great beer and fiddle with cool gadgets. :tank: Oh, and not dying of botulism would be an added benefit. ;)
 
passedpawn said:
If you don't boil your wort before you put it into your jars, I'd think you might end up with something fermenting in there.

People talking about reboiling. Doesn't that mean it was boiled once already? So confused.
 
passedpawn said:
Needs to be boiled before bottling. Then boiled again when used for starter. Sorry for the confusion.

Even when pressure boiled, I should boil again before using as starter wort? Thanks.
 
Even when pressure boiled, I should boil again before using as starter wort? Thanks.

Nope, you could run off of your mash or just add some dme/lme and water to the jar and pressure boil/can. That's the whole point of pressure canning the wort so you don't have to boil/cool to make your starter.
 
Even when pressure boiled, I should boil again before using as starter wort? Thanks.

Scenario 1: Use a Pressure Canner
Pressure canning can get the wort above 250F which is required for sterilization - which kills botulism spores. If the wort is pressure-canned, it will be sterile, and you can store indefinitely on the shelf. When you use it, it does NOT need to be boiled again.

Scenario 2: No Pressure Canner - only boiling
If, however, you don't have a pressure canner, you can boil the wort then store in jars (or bottle with your normal capper). Boiling does not sterilize the wort because it can only reach 212F. At this temperature, the botulism spores are not killed. The botulism toxin is eliminated. It's the toxin that is a problem. Now, since the spores are still in there, they could I guess produce more toxins while in your jars. This is what causes food poisoning. So, when you open the jars, you need to boil again to neutralize the toxins.

At least this is the way I understand it. Of course, as usual, I'm regurgitating what I've read on the webz.
 
passedpawn said:
Scenario 1: Use a Pressure Canner
Pressure canning can get the wort above 250F which is required for sterilization - which kills botulism spores. If the wort is pressure-canned, it will be sterile, and you can store indefinitely on the shelf. When you use it, it does NOT need to be boiled again.

Scenario 2: No Pressure Canner - only boiling
If, however, you don't have a pressure canner, you can boil the wort then store in jars (or bottle with your normal capper). Boiling does not sterilize the wort because it can only reach 212F. At this temperature, the botulism spores are not killed. The botulism toxin is eliminated. It's the toxin that is a problem. Now, since the spores are still in there, they could I guess produce more toxins while in your jars. This is what causes food poisoning. So, when you open the jars, you need to boil again to neutralize the toxins.

At least this is the way I understand it. Of course, as usual, I'm regurgitating what I've read on the webz.

Cool. I do option 1 so I wont be on the news for spreading botulism.
 
manoaction said:
What about the acid? What if you added a bit of citric acid to the wort to make it as acidic as a pickle?

Would that interfere with the starter? Isn't wort already fairly acidic?

This place says the bacteria can't grow at a ph of 4.5 or lower.
http://www.ecolab.com/PublicHealth/Cbotulinum.asp

Thoughts?

Doesn't citric acid inhibit o2 or something. Thought it prevents oxidation.
 
So... You've got yourself a quart of boiled wort that is the ph of my tap water, which is 8. (My alkalinity is 36.2 if you're following along at home)

Bru'n Water tells you to add .1 grams of powdered citric acid to it, and that reduces it to a ph of 4.5.

You store.

Then you open the wort, add 1 gram of Pickling Lime and you should be back up to 5.5 where our yeast loves to live.

Thoughts? Can we get a chemist in here to tell me if I'm off my rocker?


Doesn't citric acid inhibit o2 or something. Thought it prevents oxidation.
eh... give it a shake to get more o2 back in there.
 
Nope, you could run off of your mash or just add some dme/lme and water to the jar and pressure boil/can. That's the whole point of pressure canning the wort so you don't have to boil/cool to make your starter.

If you do this, you will get considerable hot break in your jars, at least w/ all grain. Easy enough to decant, but I'm going w/ the pre-boil next batch.

-d
 
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