How Long Could Wort Sit Before the Boil?

[TAK]

How long do you suppose wort can sit after the mash before the boil without I'll effect?

The reason for my question isn't exactly as straightforward as one might expect. Not that the reason, matters, but this is why I ask... I always adjust my gravity and volume, preboil, to my recipe. Sometimes, due to better than expected efficiency, this requires me to dilute preboil, and then remove the extra volume. Grain is relatively cheap, I know, but I still hate to throw out wort. So, I am trying to start using the extra wort elsewhere.

Over the last year, I've gotten into sour fermentations. The last time I had extra wort on brewday, I got this idea. I started a mixed fermentation project which is, and will likely continue to be, fed solely by extra wort from other batches. The last time I had extra wort, I had a whole gallon of it. I diluted it down and boiled it with a pinch of hops to get about 2.5 gal of 1.030'ish OG wort.

Two boils back to back is a long day for me though. I typically brew in the morning. So, I wonder how the extra wort would do if I let it sit half a day, and I do my second boil at night? Or even, if it sat for a whole day, and I do my second boil the next morning?

What could potentially go wrong?

Should I, or would it help to, adjust the pH down to 4.5 if it's going to sit for a day?

 

[Qhrumphf]

I would suggest that you heat your wort to >170F before letting it sit. That'll denature any enzymes (not sure if you do a mashout), because any enzymes that haven't been denatured will keep cleaving away and can potentially make a wort more fermentable than you want.

The other, more important reason to do that is that it'll also pasteurize your wort. That should keep it plenty stable for boiling later on, or even leaving overnight. I don't think I've personally ever left wort overnight (although I know others have), but I've certainly let wort sit for 7 or 8 hours before boiling with absolutely no detectable ill effects.

 

[oldstyle69]

ive always saved extra wort and made starters from them later in the week. as long as you either use it right away or chill it down for storage, i dont see it going bad any time soon. it is mostly sugar, but does have protein, so getting it cold in quick manner is better. just my guess. could be very wrong.

 

[TAK]

I would suggest that you heat your wort to >170F before letting it sit. That'll denature any enzymes (not sure if you do a mashout), because any enzymes that haven't been denatured will keep cleaving away and can potentially make a wort more fermentable than you want.

I should've mention, yes, I'd definitely take it up to about 175F for a bit while still in the kettle before drawing off the excess.

ive always saved extra wort and made starters from them later in the week. as long as you either use it right away or chill it down for storage, i dont see it going bad any time soon. it is mostly sugar, but does have protein, so getting it cold in quick manner is better. just my guess. could be very wrong.

How do you store it before boiling it later in the week?

 

[oldstyle69]

ive kept it in large ball jars and held them for over a month before using them for starters.

 

[passedpawn]

As long as you're going to boil it later, there's no limit with respect to safety.

Flavor will be affected if spoiling organisms take hold. But if the wort hits 170F and the container you put them in is sterile, no problem.

 

[muels]

Thought I read something about botulism if it isn't done in a pressure canner. I'm just regurgitating what I thought I read so please research on your own.

Edit - I mean for longer term storage

 

[Qhrumphf]

Thought I read something about botulism if it isn't done in a pressure canner. I'm just regurgitating what I thought I read so please research on your own.

Edit - I mean for longer term storage

In this instance, it's not an issue. Botulinum bacteria are not harmful in and of themselves, and neither are their spores. It's the toxin that they produce that is harmful, and that toxin is destroyed by boiling. The OP is going to be boiling this wort later on, making botulism irrelevant. As far as I recall, botulism has no taste or flavor impact either. The bigger concern is wild yeast or bacteria, or even something enteric.

The pressure canner advice is normally given to brewers who want to can wort for starters so that they don't have to boil it later on, just combine with yeast. There, botulism could be an issue (although still incredibly unlikely, the pressure canner advise is just an abundance of caution).

 

[muels]

Thank you for clarifying

 

[paperairplane]

Ever forget to ditch your spend grain after a brew day and leave it in the 95* garage for a day or two? That's a unique smell.

 

[cjones]

Ever forget to ditch your spend grain after a brew day and leave it in the 95* garage for a day or two? That's a unique smell.

lol.... unique.... [emoji40]

 

[Qhrumphf]

Ever forget to ditch your spend grain after a brew day and leave it in the 95* garage for a day or two? That's a unique smell.

Ever have the (dis)pleasure of judging the sour category at a comp, and get a poorly sour mashed Berliner Weisse? Same thing. Butyric acid (and probably some isovaleric acid too) is what you're smelling. The enteric bacteria in your grain bed and in the environment overall. Rotting parmesan cheese and vomit is how I percieve it. It's not pleasant.

 

[passedpawn]

Thought I read something about botulism if it isn't done in a pressure canner. I'm just regurgitating what I thought I read so please research on your own.

Edit - I mean for longer term storage

Exactly - botulism spores can create the toxin in closed containers of wort. But if you boil it before use any toxin in the stored wort is destroyed. So, as long as stuff is boiled there's no health concern.

 

[paperairplane]

Exactly - botulism spores can create the toxin in closed containers of wort. But if you boil it before use any toxin in the stored wort is destroyed. So, as long as stuff is boiled there's no health concern.

While this is correct, I wouldn't call it a best practice.

 

[passedpawn]

While this is correct, I wouldn't call it a best practice.

I agree 1000%.

 

[chudsonvt]

Ever forget to ditch your spend grain after a brew day and leave it in the 95* garage for a day or two? That's a unique smell.

All too often. I commonly brew after work and by the end of the night I'm so tired that I say screw it, I'll take care of it later. I have come to the conclusion that this is not worth getting to bed earlier. lol

 

[TAK]

I wasn't under the impression that the toxin is made inert by boiling. Boiling will kill the bacteria, but not their spores; boiling temps aren't hot enough to kill those. And then there's the toxin, which is a chemical, not an organism. Are we sure that boiling degrades it? Maybe it does, but I don't know how I'd feel about it. However, I would feel more comfortable if the wort was pre-acidified to <4.5, which should inhibit the enteric bacteria.

On the botulism front, I'll play it better safe than sorry.

On other front fronts, butyric acid, etc., how long is a reasonable "safe zone" do people suppose? No chance of catching off flavors like that within 12 hours, right? How about 24? Would the pre-acidification hedge this risk as well?

 

[chudsonvt]

I wasn't under the impression that the toxin is made inert by boiling. Boiling will kill the bacteria, but not their spores; boiling temps aren't hot enough to kill those. And then there's the toxin, which is a chemical, not an organism. Are we sure that boiling degrades it? Maybe it does, but I don't know how I'd feel about it. However, I would feel more comfortable if the wort was pre-acidified to <4.5, which should inhibit the enteric bacteria.

According to Wikipedia, the botulinum toxin is denatured and effectively deactivated at 179°F. However, the spores are not. However high sugar content and low PH also prevents growth. So after the boil, the bacteria is dead and the toxin is denatured. So any spores (harmless on their own) will initially not want to grow due to the sugar concentration and then will not want to grow because of the low PH after fermentation. And it should nto be a problem in your body because of stomach acid. The spores naturally exist all around us with no problem.

So long story short, boiling should suffice on the botulism front.

 

[christyle]

I think the bigger question here is how you're getting an extra gallon of wort....

 

[Qhrumphf]

According to Wikipedia, the botulinum toxin is denatured and effectively deactivated at 179°F. However, the spores are not. However high sugar content and low PH also prevents growth. So after the boil, the bacteria is dead and the toxin is denatured. So any spores (harmless on their own) will initially not want to grow due to the sugar concentration and then will not want to grow because of the low PH after fermentation. And it should nto be a problem in your body because of stomach acid. The spores naturally exist all around us with no problem.

So long story short, boiling should suffice on the botulism front.

More or less.

The sugar content in wort is not high enough to inhibit botulism. If it were, it would be a non-issue. Wort can grow botulism when kept anaerobic for long enough.

Once it ferments though, it's pH and ethanol that will keep it from ever growing. Botulinum toxin does not form overnight and the short time between boiling, chilling, and pitching/fermentation is more than enough to prevent it.

As far as I know, there is not one recorded instance of brewing-related botulism poisoning even with people not following the recommended procedures to prevent it, so it's kind of a non-issue anyway. But I understand and support the abundance of caution there.

But if you're pasteurizating first and keeping sealed and in a sanitized container, there's no reason you couldn't keep it a few days before boiling, especially if it's stored cold.

Hell, I'd give it a shot. It's actually a good way to test your cleaning and sanitizing process. Normally you'd boil first so you would see a reduction in timeframe, but seeing how long wort takes to spontaneously ferment is a good way to tell if you've got a weak link somewhere.