Questions about Preboil volumes

[The_Dtrain]

Hey all--

I've completed 3 AG batches using batch-sparging techniques. Efficiencies have been decent (~75% according to BrewAlchemy). I'm following the instructions by RichBrewer with regards to mash volume and sparge volumes. I typically input 6.5 gal as my preboil volume into my software but I've been ending up with over 7 gallons. Most of my recipes have called for around 10-11 lbs of grain and my OGs were planned to have been around 1.050 (and came pretty close).

In order for me to get down to my 5.5gal post-boil volume I need to boil for about 2 hours. Is this bad? The batch that I brewed Friday ended up with about 7.75 gal pre-boil volume. It took over an hour to get to the point where I could start my hop additions (based on a 60 min boil). I have general idea about what my boil-off rate is but nothing concrete. In fact I adjusted my times on the fly based on what the boil-off rate was so my total boil time was over 2hrs.

Is there a trick/technique reducing down to 5.5gal or sparging to not get so much wort? Or am I doing the right thing and I do I just deal with the high volumes?

Thanks,
Dtrain

 

[oldschool]

I ran in to that problem myself a while back. I changed my methods and still get a little over 75% eff. Just mash as normal and take your first runnnings. If you have a sight glass on your kettle it will be easier. If you know that you can boil off 1.5 gallons/hour and you shoot for 5 gallons, just collect a total of 6.5 gallons. It's that easy. I do it this way and still hit the 75% mark. Just be sure that your mash reaches 170 during the sparge. It will really help your effeciency.

 

[northernlad]

Find a spoon or a twig or whatever and mark it at the 6.5 gallon level of your BK. Collect runnings to that level regardless of what the calculator tells you. I run a soft boil for 60 minutes and get 5.25-5.5gal into the fermenter.

 

[The_Dtrain]

I have a sight glass on my kettle, which is very helpful. I'm just concerned about the loss of efficiency if I leave all that liquid in the MLT. Maybe I should try parti-gyle with what's left.

 

[Yooper]

I have a sight glass on my kettle, which is very helpful. I'm just concerned about the loss of efficiency if I leave all that liquid in the MLT. Maybe I should try parti-gyle with what's left.

I understand the concern about the loss of efficiency. It's true that sparging more will increase the %, but then as you've found you have to boil longer to get the finished volume correct.

Unless you're making a "big" beer, though, I don't think a partigyle would be warranted. I would be willing to bet if you sparge to your boil volume, and then do another (separate) sparge with the excess water, your OG will be surprisingly low. If you actually sparge with the amount of water to get you to your boil volume, and addition small sparge will produce some wort but I'd guess that the OG would be in the 1.017-1.020 range (maybe even lower). Not enough to worry about.

Maybe do an experiment. Mash and drain the first runnings as usually. Measure them- if you have 2 gallons, sparge with two equal batch sparges of 2.25 gallons. (That's 6.5 gallons, right? ) After you run those off, add another gallon or so and drain. Check the SG. I'd be willing to bet that it would be low, and not worth worrying about.

What you can do now to help with the volume calculations in Beersmith, since it's always too high, is add .5 gallon to your deadspace and that should stop you from being so far over your volume everytime. You should NEVER be leaving any liquid in the MLT- that's what I hear you saying here, that you'd be leaving liquid in the MLT. You don't want to do that- you want to drain it completely when you're batch sparging. So, fix the volume going INTO the MLT and your efficiency won't suffer.

 

[The_Dtrain]

Thanks for the tips. I'll try decreasing my sparge volume based on my initial runnings and see how things go.