Can I store and use unboiled wort for a starter?

I ended up with too much wort in my kettle so I ran off about a gallon into a small kettle that I covered and put in my fridge. I normally make starters with DME, but I'm thinking that I can just boil this 'unboiled' wort and make a starter with it.

BUT - i'm worried the wort might spoil or something or maybe will have an off flavor from sitting in the fridge.

I know Granite State Breweries ship unboiled wort to their local brew houses and do the boil and hops and fermentation in the local breweries. Therefore, this is obviously possible to do.

I'm wondering if any of you have done this? If it works well, i'll probably do it frequently.

Your thoughts are appreciated. We are in a never ending quest to cut costs and yeast costs are the worst imo.

Thanks.
Matt

If the wort is 1.040 or so then yes you can save it. If it will be short term, the fridge is fine. Long term you can actually freeze it, then thaw and boil when ready and then pitch the yeast.

If it is a stronger wort then you should dilute it down. You ideally do not want to make a starter out of strong wort. The idea being that you want to grow a nice healthy crop of unstressed yeast.

Why not heat it to above 160F for a few minutes to pasteurize it...just a little added safety.

I agree with duboman on this one!

Of course you could really cut costs by slanting and culturing your own yeasts! With a minimum of expense and a little reading you could cut your yeast costs to practically nothing!

Just saying!

ah... 160F... that is a great idea.

Diluting it will actually even work better so I can stretch it even further. the OG is around 62. Any idea how I would figure out how to get it to 40? Perhaps add 25% water?? If I have a gallon of wort at 1.062 and I add just over a quart of H2O, that should get me close enough to 1.040 right?

bierzwinski said:

ah... 160F... that is a great idea.

Diluting it will actually even work better so I can stretch it even further. the OG is around 62. Any idea how I would figure out how to get it to 40? Perhaps add 25% water?? If I have a gallon of wort at 1.062 and I add just over a quart of H2O, that should get me close enough to 1.040 right?

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That sounds about right. In addition, if you make a larger starter than you actually need you can harvest yeast directly from the starter and save that. If I remember right there was just an on line article in How To Brew magazine on this.

I would do every thing that the above post says, but what I do is actually take the wort and bring it to a boil then put it inside a sanitized 1/2 milk jug and then but it in the freezer. I think that bringing it to a boil is key to it keeping longer.

bierzwinski said:

ah... 160F... that is a great idea.

Diluting it will actually even work better so I can stretch it even further. the OG is around 62. Any idea how I would figure out how to get it to 40? Perhaps add 25% water?? If I have a gallon of wort at 1.062 and I add just over a quart of H2O, that should get me close enough to 1.040 right?

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Since water is 1.000, it's easy to do a little math to dilute it to 1.040.

I'd definitely bring it to a quick boil before chilling in the fridge. If you're using it right away, then a short stay in the fridge is fine. Otherwise, what I've done is boil it up really quick, cool, then put it in the freezer in a tupperware pitcher for use later on.

well looks like several people said that already sorry for being repetitive

Thanks guys. this all sounds easy enough. We were too busy with the rest of the brew to boil that right then. It has been in the fridge since Sat. around 3pm. I'm assuming I could just boil it tonight and put it back in the fridge until I get to it next week. Would you agree with that?

@KevinW - I'm working on not buying yeast anymore. It is a matter of laziness for me. But what I do now is make multiple starters with one vial of Whitelabs and keep one starter to make others with.

I didn't know an OG of 1.040 was that important. How important is that really? If the wort is at a higher OG, won't I get more yeast out of it since there is more food for it to use to replicate?

bierzwinski said:

Thanks guys. this all sounds easy enough. We were too busy with the rest of the brew to boil that right then. It has been in the fridge since Sat. around 3pm. I'm assuming I could just boil it tonight and put it back in the fridge until I get to it next week. Would you agree with that?


I didn't know an OG of 1.040 was that important. How important is that really? If the wort is at a higher OG, won't I get more yeast out of it since there is more food for it to use to replicate?

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Taste it. If it's got any sourness to it, toss it. Unboiled wort turns sour fast, even in the fridge, due to the lactobacillus on the grain.

There are good reasons for the 1.040 figure, but the short answer is you want the yeast to be healthy, and reproduce without stress. The best way to do that is give them a small job, to enhance reproduction. After all, the point of a starter is growing yeast and not making a higher gravity beer!

Thank Yooper. that makes good sense.

What about getting some canning jars, boiling the extra wort (I would look at collecting the last bit of you sparge instead of taking from the kettle) to kill off anything then pouring the wort into the (preheated) canning jars till they overflow and screw on a lid. Leave to cool then clean off any residue and stick in the fridge (or would you even need to?).
Would this help anymore or just add extra effort where it is not needed, I like the idea of using canning/mason jars as the are easy to store and are sealed.

bierzwinski said:

Thanks guys. this all sounds easy enough. We were too busy with the rest of the brew to boil that right then. It has been in the fridge since Sat. around 3pm. I'm assuming I could just boil it tonight and put it back in the fridge until I get to it next week. Would you agree with that?

Yup, that should be fine, if you decide to go longer then boil and freeze

@KevinW - I'm working on not buying yeast anymore. It is a matter of laziness for me. But what I do now is make multiple starters with one vial of Whitelabs and keep one starter to make others with.

I didn't know an OG of 1.040 was that important. How important is that really? If the wort is at a higher OG, won't I get more yeast out of it since there is more food for it to use to replicate?

Click to expand...

SO... the idea of the starter is to create a controlled, healthy growth of cells up to the ideal pitching rate and you want something simple and easy for the yeast to eat without creating any undue stress. According to the yeast experts, 1.040 is the ideal gravity to be used for a starter. Just because you increase the food does not translate to more healthy yeast. It actually becomes a problem with the possibility of underpitching your starter which is the same as under pitching your beer, just on a smaller scale

well looks like several people said that already sorry for being repetitive

mattd2 said:

What about getting some canning jars, boiling the extra wort (I would look at collecting the last bit of you sparge instead of taking from the kettle) to kill off anything then pouring the wort into the (preheated) canning jars till they overflow and screw on a lid. Leave to cool then clean off any residue and stick in the fridge (or would you even need to?).
Would this help anymore or just add extra effort where it is not needed, I like the idea of using canning/mason jars as the are easy to store and are sealed.

Click to expand...

You can do this but you will want to use a pressure canner if it is not going to be used quickly or is not going to refrigerated/frozen after it is produced. Even if refrigerated I would suggest quick use. Due to pH/sugar content wort is not stable unless heated to 250 degrees (15 psi) for 15 minutes.

Good idea. one of my main goals is to eliminate buying DME as it is much more expensive than grain, but I don't want to do a 'special' mash just for starters.

Thanks for all the input guys.

Brad2287 said:

You can do this but you will want to use a pressure canner if it is not going to be used quickly or is not going to refrigerated/frozen after it is produced. Even if refrigerated I would suggest quick use. Due to pH/sugar content wort is not stable unless heated to 250 degrees (15 psi) for 15 minutes.

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Is that because food spoilage microbes are not kill at 100°C/212°F?

mattd2 said:

What about getting some canning jars, boiling the extra wort (I would look at collecting the last bit of you sparge instead of taking from the kettle) to kill off anything then pouring the wort into the (preheated) canning jars till they overflow and screw on a lid. Leave to cool then clean off any residue and stick in the fridge (or would you even need to?).
Would this help anymore or just add extra effort where it is not needed, I like the idea of using canning/mason jars as the are easy to store and are sealed.

Click to expand...

Brad2287 said:

You can do this but you will want to use a pressure canner if it is not going to be used quickly or is not going to refrigerated/frozen after it is produced. Even if refrigerated I would suggest quick use. Due to pH/sugar content wort is not stable unless heated to 250 degrees (15 psi) for 15 minutes.

Click to expand...

mattd2 said:

Is that because food spoilage microbes are not kill at 100°C/212°F?

Click to expand...

Yes. A water bath canner even won't cut it for wort, and a pressure canner is needed for this process.