More strike than sparge water... why?

Hopefully, as I type this, I'll figure out what's going on. I've been doing my math like this:

Say I have 13lbs of grains (seems to be my average lately). I stick with the 1.33-1.5qt/lb ratio for my strike water. I'm brewing 5 to 5.5 gals hopefully. That's 17.29 qts or just over 4.25+ gals of water. I usually heat up 4.5 gals expecting a little to go off in steam. I drain that after my mash and get about 3.5+ gals... well, my boil off rate is a little less than 1gal an hour, so it seems, so I want to have about 6+ gals total pre-boil. That means for my sparge water I only need about 2+ to 3 more gals of water. That's significantly less than my strike water.

I've been using this method and getting 60-70% efficiency, usualy around 65-70 but has been lower. Seems to be working out ok for me, but I notice when most people talk about their mashing session they tend to have a significantly larger amount of sparging water than strike water.

What's going on? Why does it tend to be that way for everyone else? Am I calcuating something WAY off here?

"I drain that after my mash and get about 3.5+ gals... well, my boil off rate is a little less than 1gal an hour, so it seems"

Don't forget about the water that is absorbed by the grain.

I use a very similar procedure, with very similar efficiencies. I usually aim for 1.25 qts. per pound, drain, then add whatever amount of water I calculate I will need to hit 5 gal. after the boil (usually 25-50% less than 1st runnings). I only recently purchased a refractometer, so I have slowly been trying to modify my procedure to shoot for the gravity and volume I want post boil. Refractometers make gravity readings painless. Once I know the gravty and volume in the pot after sparging, I adjust the boil length (evaporated volume) accordingly. This way, the only thing that my efficiency for that batch affects is the boil length, not the end product.

On another note, I have been looking to a malt mill to take the HBS crush out of the picture as a variable - not sure if you crush your own.

I'll be interested to hear others' response on this topic.

Really, with 13 lbs of grain for a 5 gallon batch, if you want to get all the good stuff out you'll have to sparge more, end up w/ more pre-boil volume, and boil longer.

The other thing is you're mashing a little thinner than you have to. For example, Papazian's formula says 1 qt/lb mash + 2 qt/lb sparge. For 13 lbs of grain, that would be 3.25 gal, after absorbtion you're left with ~1.75 gal. The sparge volume would be 6.5 gallons for a total of 8.25 gal pre-boil. So shooting for 6-6.5 gal pre-boil is a little low if you want to fully sparge your grains.

If you want to go this route but your kettle won't hold it, sparge until the kettle's full, and then sparge the rest into another container. Start your boil and add the rest of the wort as you have room. Just be careful and adjust your hop additions accordingly. If you want to stick to the same hop schedule, wait until all the wort has been added and you've got ~ 6.5 gal to start your 60 min clock.

Now, with all that said, if your kettle only holds that much and you don't feel like doing a 90+ min boil, stick to what you've got. The beer will turn out just fine even though you'll be leaving some goodness behind in the mash.

That sounds right for batch sparging. If you were doing smaller grain bills, you'd have less strike water and therefore more sparge water.

nealmc said:

"I drain that after my mash and get about 3.5+ gals... well, my boil off rate is a little less than 1gal an hour, so it seems"

Don't forget about the water that is absorbed by the grain.

I use a very similar procedure, with very similar efficiencies. I usually aim for 1.25 qts. per pound, drain, then add whatever amount of water I calculate I will need to hit 5 gal. after the boil (usually 25-50% less than 1st runnings). I only recently purchased a refractometer, so I have slowly been trying to modify my procedure to shoot for the gravity and volume I want post boil. Refractometers make gravity readings painless. Once I know the gravty and volume in the pot after sparging, I adjust the boil length (evaporated volume) accordingly. This way, the only thing that my efficiency for that batch affects is the boil length, not the end product.

On another note, I have been looking to a malt mill to take the HBS crush out of the picture as a variable - not sure if you crush your own.

I'll be interested to hear others' response on this topic.

Click to expand...

Just recently started crushing my own and getting good efficiencies. Now, I did take into account the water absorbed that's why I said I collect about 3.5+ gals when draining after using 4.5+ strike water. I calculate the rest I need to get 6+ and its usually way less then my initial strike water amount.

Lil' Sparky said:

Really, with 13 lbs of grain for a 5 gallon batch, if you want to get all the good stuff out you'll have to sparge more, end up w/ more pre-boil volume, and boil longer.

For example, Papazian's formula says 1 qt/lb mash + 2 qt/lb sparge. For 13 lbs of grain, that would be 3.25 gal, after absorbtion you're left with ~1.75 gal. The sparge volume would be 6.5 gallons for a total of 8.25 gal pre-boil. So shooting for 6-6.5 gal pre-boil is a little low if you want to fully sparge your grains.

If you want to go this route but your kettle won't hold it, sparge until the kettle's full, and then sparge the rest into another container. Start your boil and add the rest of the wort as you have room. Just be careful and adjust your hop additions accordingly. If you want to stick to the same hop schedule, wait until all the wort has been added and you've got ~ 6.5 gal to start your 60 min clock.

Now, with all that said, if your kettle only holds that much and you don't feel like doing a 90+ min boil, stick to what you've got. The beer will turn out just fine even though you'll be leaving some goodness behind in the mash.

Click to expand...

I've considered that route for sure, adding as some evaporates. I don't mind the long boil, but does 90+ minutes not effect the taste of your wort?? Seems like cooking it longer would adjust the flavor.

seefresh said:

I've considered that route for sure, adding as some evaporates. I don't mind the long boil, but does 90+ minutes not effect the taste of your wort?? Seems like cooking it longer would adjust the flavor.

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The only difference will be how much volume you're boiling off as long as you're not burning any of it. The difference in taste will be that you have a higher OG beer.

Lil' Sparky said:

The only difference will be how much volume you're boiling off as long as you're not burning any of it. The difference in taste will be that you have a higher OG beer.

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Awesome! I'm gonna do that next time. I had about 1.5 gals of extra wort pre-boil 2 brews ago. It felt like such a waste, but I thought too long of a boil would hurt the flavor of my beer.

I'm glad to boil longer times. When I'm boiling wort I have an excuse to sit on my porch, play guitar and puff cigars

When I first got into brewing I was visiting some different boards, and I found that a lot of people do standard 90 min boils.

When I'm boiling wort I have an excuse to sit on my porch, play guitar and puff cigars

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Dude, that's what it's all about.

seefresh - I noticed you're in Germany. Are you in the military?

My wife is (dental assistant specialist) I'm a internet developer and work from the house so I get to reap all the benefits of living in Europe and still grow a beard.

We are heading to Texas in 6 months though, been a helluva stint over here.

Very cool. I've been in the Air Force for 10 years. I've got the cush assignment right now - working on a PhD in Computer Science to go back and teach at the Air Force Academy again. I'll have to do a real job between here and teaching, and I really hope to get over to Germany for an assignment. Where in TX are you headed? SA?

seefresh said:

Just recently started crushing my own and getting good efficiencies. Now, I did take into account the water absorbed that's why I said I collect about 3.5+ gals when draining after using 4.5+ strike water. I calculate the rest I need to get 6+ and its usually way less then my initial strike water amount.

Click to expand...

I misread - sorry. I thought you calculated your boil-off by 4.5-3.5=1 gal. I see now that I need another cup or three of coffee.

Shepperd AF Base... just for 6 months while she gets some dental lab training.

Well, it's not the armpit of TX, but you can smell it from there.

Cheers.