Store Wort for yeast starter

[tll77]

I have been canning wort for many years which makes it very easy to make a starter. I do have a question from a recent canning batch:

I had one jar not pop and seal the lid. I tightened the lid and put it in the fridge for use first on my next brew. My thinking is that everything was killed with the 15 min. at 15psi so it should remain sterile while it sits in the fridge closed up. Am I right is it a risk?

Thanks

When I have had this happen I just reprocess the jar.
Make sure the lid seal and the mouth of the jar are clean and that the jar is not over filled.

 

[specialkayme]

I still think the odds are quite low that if a canned jar hasn't lost its seal after a month that there still may be a botulism infection present. Most everything I've read indicates that the botulism toxin is created in 3-5 days when optimum conditions are present.

But . . . I get the point. Any chance that is greater than zero of instant death is something I'd like to avoid.

So what about an alternative? I do no sparge brewing, and I have left over residual sugars present in the grains after brewing. Why spend money on DME if I don't have to?

From what I've read, Clostridium botulinum, the bacteria that produces the botulinum toxin, can grow in environments from 40–120 °F (4.4–49 °C) when the pH is above 4.6, the oxygen level is below 2%, and the water activity is above 0.85.

So, if I take my second "runnings" and it comes out at 1.040, and I don't pressure can it, I can freeze it (discussed above), keep it above 120 degrees (not very practical), reduce the pH below 4.6 (not optimal for yeast growth), or reduce the water activity below 0.85.

In order to reduce the water activity below 0.85, I'd have to have approximately 67g of sugar for each 100g of water. That would give me a SG of roughly 1.25.

Now, If I had 3 gallons of 1.040 wort, and I boiled it down to 0.5 gallons, I should have a solution with an SG of 1.25, which means botulism wouldn't grow in it, right? Then, I should be able to add one part of this solution to five parts water to get yeast starters in the future. Basically making LME at home.

I don't know if it justifies the time and energy to make, when compared to buying DME, but it should work in theory, right?

 

[z-bob]

@specialkayme You skipped an easy one: Just store it in the refrigerator at 35°F. Couple of quarts. If one develops mold (unlikely but possible) use the other one. If they both go bad, use the DME you keep in reserve just for that possibility. Then save a quart or two from your new brew to replace the one(s) you used.

 

[specialkayme]

@specialkayme You skipped an easy one: Just store it in the refrigerator at 35°F.

True. Not sure how I skipped that.

Of course consuming more fridge real estate may lead to a quicker death from the significant other than the botulism may provide, but we all have to pick our poisons though

 

[SanPancho]

You dont even need the fancy bottles. Regular flask is fine. If you make up some sterile (or damn close) ice cubes then you can be done in 5 minutes. No need for overnight cooling.

Dump dme in flask, cover with 30-40% of the water you need and zap it till it gets hot enough.

Drop in ice cubes until you get to pitch temp. Top off with your sterile water, i.e. purified, bottled, distilled, etc.

Literally a 5 min process. Just need to have your ice ready.

 

[Vale71]

In order to reduce the water activity below 0.85, I'd have to have approximately 67g of sugar for each 100g of water. That would give me a SG of roughly 1.25.

This is exactly what keeps liquid malt extract from spoiling. It's concentrated to the point that most nasties don't have enough available water to grow. Unfortunately mold needs very little water so spoilage through mold ist still a possibility.

 

[pvpeacock]

Yes, they do. Until one goes bad on you and you get food poisoning...

My first reaction was that you were overreacting and what I was doing was perfectly safe because the wort was boiled in the microwave and then sealed hot. However, your post got me to do some research and you were absolutely right. Boiling does not kill the botulism spores only the toxin. Since I was using the bottled wort for starters, I never boiled it again. So, if it went bad, the toxin would go right into my beer.

A sincere thanks Vale71. I’ll be making starter wort fresh from now on.

 

[Bassman2003]

My understanding is that the spores will be killed at the 250f pressure canning temp though.

 

[Vale71]

My understanding is that the spores will be killed at the 250f pressure canning temp though.

Yes, they will.

 

[Bottoms_Up]

I freeze extra runnings from brew day in milk jugs. When needed, just thaw and use. It's not as easy as room temp storage, but i don't have to worry about botulism.

I like that approach. Do you boil the wort again after thawing?

 

[IslandLizard]

I like that approach. Do you boil the wort again after thawing?

I would, yes!

 

[InspectorJon]

Resurrecting an old thread.

I have used second runnings for starter wort for a couple years now. If the gravity is too low I boil it on the stove while my beer wort is boiling until I get 1.035 - 1.040. I then cool it, put it in PET soda bottles and freeze. Be sure to leave a couple inches of empty space at the top of the bottle. Essentially free starter wort. I boil it for a few minutes after thawing. This sanitizes it and you get the hot and cold break, reducing trub in the starter. After boiling, cool it in ice water to pitching temperature.

 

[Bottoms_Up]

Resurrecting an old thread.

I have used second runnings for starter wort for a couple years now. If the gravity is too low I boil it on the stove while my beer wort is boiling until I get 1.035 - 1.040. I then cool it, put it in PET soda bottles and freeze. Be sure to leave a couple inches of empty space at the top of the bottle. Essentially free starter wort. I boil it for a few minutes after thawing. This sanitizes it and you get the hot and cold break, reducing trub in the starter. After boiling, cool it in ice water to pitching temperature.

That is exactly what I've been doing lately.

I start out with 3 liters (I generally use a 3 liter yeast starter so I can later save one liter for the next starter and use the remaining two liters in the lager I'm making) and boil it down to the reduced volume needed to fit the bottles and allow for the expansion of ice. I allow 7% space in the PET bottles for expansion of the ice. Ice expands to 9% but the pressure produced in the bottles reduces it to about 7%. I then pour the wort in the bottles at about 180-190 F, squeeze them to let out the air, and freeze them.

When I'm ready to use them, I let them thaw out at room temperature (takes about 3/4 day), or you can put them in a sink of hot water for much faster thawing. I put this in a pot, add enough water to get it back to 3 liters, plus some for loss during boiling, and then I boil it for 15 minutes, topping up with water when needed to get the right volume (and specific gravity). I use a small measuring dowel to determine if I have the right volume (volume measurement adjusted for boiling temperature).

I then pour the 3 liters of wort in an Erlenmeyer flask and add yeast. Then I start the yeast stirrer. Once done, I save one liter of this in a Mason jar (refrigerated) to use for my next yeast starter, and place the remaining 2 liters in a larger Mason jar and refrigerate it. After a few days, the yeast will have mostly settled to the bottom (lager yeast takes much longer to settle than ale yeast). I pour off the clear liquid, and add the yeast slurry to the beer I'm making.

 

[cactusgarrett]

I like that approach. Do you boil the wort again after thawing?

Absolutely. It wasn't boiled in the first place. Even if it were, I would just to be safe, anyway.