# Too Much Pre-Boil Wort?

I’m fairly new to all-grain brewing, and I’m hoping someone can help me out with what I’m missing here… My previous AG beers have been low gravity, and I’ve always just under 7 gallons of wort pre-boil. I fly sparge, and I’ve been using 1.25 qt/lb strike water, about 6 qt of boiling mash out water, and 2 qt/lb sparge water. When I look at bigger beers (let’s say 12.5# grain bill), it seems like I’d have too much pre-boil wort for a 60 minute boil. I’ve always heard that you lose about .12 gal/# of strike water to grain absorption. Using my 12.5# example, you’d have ~11.6 gallons of wort minus 1.5 gallons for grain absoption, for just over 10 gallons of pre-boil wort. Am I missing something here, or is this correct and you just stop collecting wort when you reach your target pre-boil volume? Thanks!

If you are adding 10 gallons of water but not collecting it all that is lost sugar. Like you said, some water is tied up in the grains. This water has roughly the same sugar concentration as what you are collecting, so that’s lost sugar.

This link is a batch sparge example, but the principles are similar for a fly sparge, just a little more complicated to calculate:

http://woodlandbrew.blogspot.com/2012/1 ... sugar.html

You’ll only want to add as much water as you want to collect, plus what is absorbed by the grains. So if you want a pre boil volume of 7 gallons, and your grain absorption is 1 gallon, don’t add more than 8 gallons. Sparge water temperature is not as critical as mash temperature. If you have to make a sacrifice, that’s the place to do it.

You still want to have the right amount of preboil wort so you can hit your post-boil volume with the right length of boil. Which isn’t to say you ouldn’t boil longer if its not a light-colored beer.

You do this by reducing the mas ratio down from 2qt/lb to as low as 1qt/lb. Your efficiency is going to go down simply because that extra few pounds of grain is holding more sugar water behind, so you design the recipe with a little extra malt to compensate. If its a big enough beer you might want to do a partigyle and make a small beer from that extra sugar. But a 13lb grist probably doesn’t justify that.

Using a program like Mashwater 3.3 will help you dial in the water needed for each batch of beer.

Batch/fly sparge, is doesn’t matter. The point is to have a nearly empty MT at the end.

http://suburb.semo.net/jet1024/beer/sof ... tware.html

If I ever have a little bit of pre boiled wort left, I’ll typically drain and store it in quart jars to make yeast starters with in the future. Just make sure you boil before use and that the gravity of the wort is close to 1.040. Makes great starters.

+1 - I generally plan to collect .5 to 1 gallon of final runnings for the next batches starters

+1 - I generally plan to collect .5 to 1 gallon of final runnings for the next batches starters[/quote]

Even boiling it 1st, it will have a fridge life of 4-5 days before spoiling. Just like any other food item.

Freezing works better. Even that has it’s possible down side for extended storage.

Pressure canning is the only recommended safe way to store wort.

+1 - I generally plan to collect .5 to 1 gallon of final runnings for the next batches starters[/quote]

Even boiling it 1st, it will have a fridge life of 4-5 days before spoiling. Just like any other food item.

Freezing works better. Even that has it’s possible down side for extended storage.

Pressure canning is the only recommended safe way to store wort.[/quote]

Even if you are boiling it before you make your starter? I have done this probably 30 times, some using after about two weeks. In all that time, I have had only one jar get a little moldy, so of course I did not use it. I always smell it and it it smells off at all, I do not use it.

I always boil it before I store it. I’ll boil and put it in a quart jar and let it seal. Even then there is a slight risk of spoilage, but I choose to take that.

Or a lot of times I’ll pour the trub in a pitcher and let it settle overnight in the fridge, then transfer that to a jar for storage.