How fast should you drain Mash Tun

Mase

Well-Known Member
Trial Member
Joined
Mar 16, 2017
Messages
1,616
Reaction score
1,853
Points
113
Good Morning, or Good Afternoon or Good Evening depending on where you are. So here's my question, I've read that when draining your Mash Tun with either first runnings or sparge runoff, to go slow (gallon every 10 minutes +/-), or to running off fast (Denny Conn I believe), how do you run off? I ask because it would certainly speed up the brewday if running off fast, but does that also run the risk of missing your numbers. In my opinion (all of 9 brews-worth of experience), if you are to run off slow, wouldn't you just Mash longer? Maybe for the Sparge a slow run off may make sense for contact time, but I'm not sure contact time is needed after a 60 minute Mash (example duration) as the starches should be converted during the Mash and all you are doing is getting the last bit of sugars out of the mash and meeting your preboil volume. Or is it a "it just depends on....?
 
If you are sparging with a sparge arm or some sort of sprinkler if you go to fast it can cause compaction of the grain. If you BIAB its not an issue. I recirculate with a rims setup and so just turn wort into boil kettle at same flow, then batch sparge, stir,recirculate til clear then go to kettle again. When recirculating you have to pump slow or it will compact the grain to much. Not sure of how many gpm I'm doing never timed it but pretty sure its faster than gal per 10 min. More like gal per 1-5 min or in there somewhere.
 
I'm not sure of the reasoning behind drain slow if you're draining the first runnings completely. There should have been a mashout to stop enzymatic action before collecting wort so contact time shouldn't matter. Sugars do rinse out as the wort drains so there's some advantage in slowing things down. A slow sparge does more good in that way, I think. Loosening the sugars with sparge water slowly running through the grain bed will increase efficiency.
I do a recirculating mash and then introduce the sparge water as the tun is draining. I use a little over 1/3 of my total volume in the sparge so around 3 gallons. I use the recirc pump to sparge so I set it to just slower than the outflow and the whole drain/sparge takes around 30 minutes.I typically get close to 80% efficiency.
 
What i've read, slow lauter and sparge are to avoid compressing the grain bed and to avoid channeling. I usually take ten to fifteen minutes for both and hit or exceed my targets. I'm batch sparging for reference and use a false bottom in my ten gallons cooler mash tun.
 
I recirculate through the whole mash keeping a perfect temperature throughout the mash cycle then I do a mash out holding steady at 168ish for at least 10 minutes while still recirculating, I also heat my sparge water to the same then turn off the element and do a one hour slow sparge , the difference between slow and fast sparging on my system means 5% or so efficiency sometimes but I get on a good day close to 85% regularly, because I recirculate fairly fast my crush is bigger than most to prevent stuck sparging so it all works well, no stuck sparge, clear wort and good efficiency if I’m using a very expensive system why not do it right ;)
 
I've been crushing my barley extra fine yes I get better extraction from it but go to sparge and things get complicated.
 
One way I have found to check if I'm draining to quickly, after draining the first running-
1. turn off your valve to the tun wait 5-10 mins
2. turn it back on.
3. If I've ran off to quickly there usually is a lot of addition extract that will drain out.
Also, for my fellow batch sparge brewers- patience show be excersied after the addition of the remaining sparge water. There is more to the second running than just rinsing of the grain bed. Your sparge water needs time to penetrate the grist and free up the remaining sugars before draining again.

[conviently I listened to a pod cast on this very topic last night :D]
 
That's a great way to test first runnings. On the sparge, are you saying slow drain or let sparge sit for an amount of time before drainage or both?
 
That's a great way to test first runnings. On the sparge, are you saying slow drain or let sparge sit for an amount of time before drainage or both?

Both, I think 15 mins should be adequate for sparge water to penetrate grist and liberate remaining extract / kinda like a 2nd mashout/ followed by the appropriate draining speed for your system ( dial that in from first running trial). Usually takes me 15-20 mins to drain 3 gallons from my cooler tun , but that's my system - your mileage may vary
 

Back
Top