Charlottesville Area Masters of Real Ale

I was curious about sparge time for fly sparging. Look, for a 5 gallon batch in a 10 gallon mash tun, it takes me about 15 minutes to pump in around 4 gallons of hot water, and when I am at 6 gallons pre boil volume, the gravity is below 1.005.  So I am extracting all of the sugars.  Why then do I read so much about you MUST do a 45-60 minute sparge to get efficiency?   I was at 75% efficiency in 15 minutes with a fly sparge roatating arm (as slow as it could go at 3 feet clearance), and hit my gravity perfect. What's the deal? (45-60 minutes? Come on!), and just curious what others have seen using this method?

Thanks,

Mark.

Two words: Batch Sparge!

I like to get the best for the buck, which is why I fly sparge.  Recommended is a quart per minute.  If you have 20 quarts , then I am right on for 20 minutes. The thing I have learned is to start checking gravity around 4 gallons in the kettle and cut off the sparage around 1.008 SG.  Tannins might be cool in wine but suck in beer. And keep the sparge water below 170 deg F. 165-168 deg F.  Then QS with spring water in the kettle.  Eh?  Why would I do a batch sparge when I am set up for fly? Why would I add in 10-15% grist to hit FG? Aren't we here to save money?

With batch sparging, I usually get 70-75% efficiency so one could argue that you aren't getting anymore from the grain by fly sparging anyway. Perhaps by increasing the sparge time to be longer (45-60 min vs your 15-20 min) you would increase efficiency. But it sounds like you're saying that you are extracting all of the possible sugars with a shorter sparge time. So, I would suggest that the rate-limiting step in your mash/sparge process is the mash conversion, not the sparging. In other words, don't change what works.

Love it.  Only a postdoc would use the phrase "rate-limiting step".  Are you still postdocing over there? I like fly sparging because it is a cool process, and as a scientist, its much more involved than just dumping in water and draining. There you go.  I actually enjoy it. Now, the mash is better than the boil.  Well except for the smell of the hops going in.

I might try the newer system of the cone sparge instead of the arm, because you can run less water through it without having to worry about the arm spinning. Even at 3 feet above the mash, the arm stops spinning under low flow.  That is why I can't go slow. But still, the SG at 5 gallons collected is 1.000, so I would need to start checking around 4 gallons run-off make sure it is around 1.008, and stop it. But I think you are right. If I could do this slower, I would have higher efficiency. No doubt.

I have now got into fining with Polyclar to get rid of the tannins, regardless of when I stop the sparge. Tannins are going to be there with all-grain, and they collect at the bottom of the keg at 40 deg. F. Which is what I am experiencing now.  If you were to taste the primary or secondary, you would not taste tannins.  But they fall out of solution at keg temps.  Polyclar is the same stuff they put in pharmaceutical drugs as packing material. So it cant be that bad for you. It binds specifically to tannins and oxidized melanoidins, so its a win win. - Mark.

Well, it does not appear to me that this forum is as active as it used to be.  Bummer.  In case anyone reads this, I have an update to what I have learned.

Fly sparge optimal flow rate is 0.44 quarts/min. So an average of 1 quart every 2 minutes, Which would put my fly arm rotating twice as fast as it should. The thing is, if you have 1-2 inches of water above the grain bed, the arm does not have to be moving!!!  Just set it on a trickle and adjust the runoff flow, then stop it at 1.010 - 1.008. I have also been using the 5.2 pH product which sets your mash and lauter pH right on so you don't have to worry about pH increase during fly sparge.

I will definitely try batch sparging eventually just so I can say I have done it (Spidey maybe you can show me your process?), but fly sparging offers the challenge I am looking for. I like to be up and doing stuff when I brew, I can't stand to sit around, so it is perfect for me.  Maybe on those times when I just don't feel like dealing with fly sparge (winter cold), I will resort to batch, which is how I look at it as a benefit, but perhaps not a practice.  Yes, perhaps batch sparging would suit well for the winter time since I brew outdoors, and do fly sparge when the weather is nice. Once the kinks are worked out, I have heard of efficiencies of up to 85-90%.  That is insane and maybe a bit much if you were planning on a 75% eff.  "Well, I guess I now have an Imperial IPA!"

-M.

Doc,

Sorry, I missed your post.  I am like you.  I like to fly sparge unless environment or time-crunch circumstances push me towards batch sparging.  I have done well with both methods.  When fly sparging, I try to keep the flow slow enough to push 5 gal in about 30 min.  That puts me in the same general range as what you mentioned.

You mentioned using Five Star's 5.2 product.  Do you like it?  I have been trying to moderate my mash pH using calculations and brewing salts and I have only been moderately successful.

Cheers,

Tom

Argh! I'm caught!     Yep, still here. I don't brew scientifically (well, at least I try to do as little as possible). I like the art of brewing, not the science so much. And batch sparging lets me be lazy and I can brew more often because I can integrate (oops, there I go again) it better into my day.

I've heard some good and bad things regarding 5.2 on the Brewing Network.  You CAN use too much of the stuff and it gives a bad taste. It's great to have a tool like a 5.2 buffer in the shed, but I wouldn't rely on it 100%. Better have some back up salts for those beers that are tough to get pH'd right (I'm thinking stouts and such). Use the salts to get you in the right neighborhood and 5.2 to hold it there. Disclaimer: These are just my thoughts on the product and I haven't actually used it myself.

Hey thanks for the replies. Yes, the 5.2 does work.  I have used it a few times now with pH's around 5.2.  I was also using spring water at the time, but now have a carbon filter for tap water, so I am not sure what is going to happen there but, my guess would be that it buffers it. No off-flavors at recommended dose. Yeah you might have to add in some calcium carbonate for big stouts to raise the pH if it falls too low, but I probably would not add clacium sulfate at all with this product until boil time (after mash-out)say if you wanted to help bring out the hops, or sodium chloride if you wanted more focus on the malt.

The product description states that it is proven to: not add flavors, optimize enzymatic activity, help clarify wort, and raise starting gravities. It even stirs your mash for you.

Does anyone have a water report for Lake Monticello area (Aqua Virginia)?

For sparge time, if you can fill 1/2cup in 15 seconds, you are at the proper run-off rate.  That is slooow.

-DocM

Aqua mails out a water quality report maybe twice a year, but this gives little information regarding the solutes as brewers we are interested in.  I have not gotten a Ward Labs report for Lake Monticello water. I guess that would be the thing to do. Tom says it's super easy and only cost ~$11 or so.
I've been using a Brita tap filter for years and it works great.  But with Aqua VA's cost for water lately, it might actually be cheaper to use bottled water for brewing (and everything else that we use water for)!!! But that's a whole different matter...

I used Ward Labs to get my water tested.  As Greg says, it was very easy.  I got the household mineral test (now $13), as listed here:

http://wardlab.com/FeeSchedule/WaterAnalysis.aspx

I called the lab and they sent me a sample bottle.  I filled it up and mailed it back (you have to pay for postage to send it to the, so that costs a little bit more than the $13).  They mailed me my analysis back in about two weeks.

I brewed a ESB and I set my recipe to 70% efficiency just to be safer, for a projected gravity of 1.055. Oh, and Spidey, there is plenty of art in maintaining a perfect slow flow with a bed of grain that is compressing like an accordion : ).  There is actually a phase where the flow slows and then speeds back up. After re-cycling for a while until clear, it was time to put the sparge to the test. By measuring the flow rate with the 1/2 cup per 15 seconds (0.5L/min), I was able to continue a 1.010 run-off up until I had collected 6.5 gallons for boil.  It took about an hour, and it was actually very relaxing. My goal was to stop the sparge early around 1.008 to reduce tannins; it never reached that gravity, which meant that sugar was still coming off the grain. Much different compared to a fast flow rate that would have bottomed out to 1.000 by then. After boil, my final gravity was 1.070 at 5.5 gallons, setting my efficiency at 90% ! Now I have an Extra extra special bitter. If I were to brew this again, I would use 2 pounds less to hit gravity. By the end of a 55 lb. bag of malt, I could save enough grain to brew an extra batch of beer. Compared to batch sparge, I call that a free batch of beer!  LOL

Cheers, Doc M.

Fly sparging is a great way to get a bit more extract from your grain and not that difficult. Here @ wildwolf we lauter at a rate of 1.2 gallons per minute from a 50 gallon tun with a two foot diameter false bottom. this takes us around 30 minutes for a full kettle. for smaller batches time is not a huge problem, just run it off and be happy is what i always did. If you really want to get technical though, around .3-.5 gpm would be good for a false bottom that was about 6 inches to a foot in diameter.

Hope this helps! Come by and check out our all grain demos every saturday at noon if you are interested in how a "pro" homebrews . . .

DCW

You couldn't pay me to fly sparge on the homebrew level. The price of an extra pound or two of grain needed to make up for a minor loss of efficiency is well worth it in time saved, in my opinion.

But if you like the process and have to time to spare, go for it.