Sparge SLOWLY!

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grahamfw

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I hope this will benefit someone.

I was getting abysmal efficiencies (sub 60%) which I have fully attributed to sparging too quickly. How quickly is too quickly? Without getting volumetric, if you can see the water level going down, it's probably sparging too quickly. I recently brewed a 10 gallon batch of BierMuncher's Centennial Blonde and purchased 20% more grain to account for my bad eff. Turns out after a much slower sparge, I was able to get around 82% efficiency without changing much else at all. Needless to say, I had to dilute the cooled wort with 20% more water to get it in the neighborhood of the proper gravity.

Did anyone else learn this the hard way? Or can everyone else read? :p
 
This really depends on your brewery. I think the general rule is that a longer, slower fly-sparge will yield better efficiency, but with my system I hit my target efficiency in about 30 minutes for 12 g's of run-off. Menschmachine uses a similar technique and we have discussed it here a few times.
 
How long were your quicker sparges vs. your slower sparges? What were your sparge volumes? I am still tweaking my sparge technique.
 
I to am trying to figure out my sparging routine. That is the only thing I can think of for my less than parr efficiancy. I am also using the fly sparging method
 
Also, remember that fly sparging (or "continuous" sparging) is best done with an MLT design that draws the wort down equally from the whole surface area of the mash, rather than to one point. Otherwise you'll leave sugars near the circumference/perimeter of the MLT. Palmer does a good job explaining this here.

A round MLT with a false bottom is probably the best design for fly sparging. If you've got a small braid or Bazooka, you're better off batch sparging.
 
I have a set up where I use an insulated keg with a false bottom as a MLT. Once my mash is done I start my sparge and I can usually collect 6.5 gallons in about 35 - 45 min. It is painfully slow to watch the thing drain but well worth it because I am getting around 85% efficiency.
 
Also, remember that fly sparging (or "continuous" sparging) is best done with an MLT design that draws the wort down equally from the whole surface area of the mash, rather than to one point. Otherwise you'll leave sugars near the circumference/perimeter of the MLT. Palmer does a good job explaining this here.

A round MLT with a false bottom is probably the best design for fly sparging. If you've got a small braid or Bazooka, you're better off batch sparging.

Yes, this all made sense to me - but 2 brews ago my false bottom gave out (don't ask) and I decided to go with a braid. Having developed a real fondness for fly sparging I continued just as before with the false bottom - It has not seemed to affect my efficiency or taste or ease of sparge at all ( I sparge at a rate of 500ml -'bout half a quart-per minute so thats...just shy of an hour for 5 gallons). I am sure that there is a theoretical loss at the perimeter of my round MLT but it doesn't seem to make a big difference in my case.

Your mileage may vary.
 
when you fly sparge you never let the water level fall below the grain right? I heard the water level shoun stay at least an inch above.
 
i tht I read somewhere that the speed of lautering didnt make a difference when batch sparging - only with fly.
 
Yeah, it's a fly sparge thing. I try to fly sparge for 45 - 60 minutes.

I've been batch sparging lower grav beers lately and still hitting 85-90%, though I grind really fine. I'll likely fly sparge anything over 1.050.
 
Yeah, it's a fly sparge thing. I try to fly sparge for 45 - 60 minutes.

I've been batch sparging lower grav beers lately and still hitting 85-90%, though I grind really fine. I'll likely fly sparge anything over 1.050.

If you're batch sparging do you still need to lauter your first runnings slowly or does that not matter either? I've been getting really inconsistant efficiencies fly sparging and am gonna try batch the next couple times to see if I can get it more dialed in.
 
When I batch sparge I vorlauf, drain the mash tun as fast as possible, add all the sparge water, stir then let sit for a few minutes to settle, vorlauf then drain quickly.

Some may do it differently.

I'm mainly a fly sparger but I have been doing some batch sparges lately to save time on brew day. I'm not sure I can get the same efficiency on batch sparges with higher gravities as I can fly sparging though.

Key with fly sparging is:
  1. a consistent rate
  2. a lautering method that does not cause channeling
  3. a minimum of 60 minutes

[EDIT - Snip]

I added a sight glass to my MLT so I could see what the liquid level was at so I could see if it was dropping or rising instead of staying consistent during the sparge.

EDIT: I think this was written by Denny Conn http://hbd.org/cascade/dennybrew/
It has a decent explanation of sparging methods.
 
To answer a question in the OP - I learned the hard way too.

For about two years I had been getting crappy efficiency - usually in the 60's. I started using a friend's grain mill and my efficiency went up to the 70's but it was a pain to coordinate borrowing his mill and I didn't want to buy another beer brewing piece of equipment.

Then one brew day I had the perfect storm - just like you - I planned a recipe for eff around 70% (so a big grain bill), I used my friend's mill for a fine crush, and for whatever reason I lautered slowly. The result was my best efficiency ever - 88%. My IBU's were off, my gravity was off and it ended up being like 10% ABV. The Nottingham I pitched couldn't handle it all and it had an 'off' taste to me.

So now, my new technique is to lauter slowly. Bobby M says to open up the valve and let her rip, but lautering slowly really made a difference for me and increased my efficiency. I am very careful about opening up the valve now and it is now part of my routine.

Another part of my routine that increased my efficiency has been to mash with 2.0 qt/lb, skip the mash out and just do one sparge. Check out Kaiser's posts about this. In order to get better eff the mash-out was part of my brew day but the increase was small - however mashing with 2.0 qts/lb and lautering slowly gets me in the mid 70's for eff with the crappy crush I get from my LHBS.

Simple things you change in your process can really make a difference. Remember, if you make a change, try one at a time. What works for me may not work for you.
 
Interesting to read all this. I have always batch sparged and unless I get a stuck sparge I usually have the mlt fully drained in less then ten minutes. I shall try this slow drain stuff tomorrow and see how it comes out.
 
I guess I shouldn't post things right before I leave work if I'm not going to look at them from home!

To clarify (pun), I do fly sparge. I'm curious as to how/why batch sparging is speed-independent. I guess any channeling in the first batch would be mitigated by the subsequent batch and stirring.

I also changed from having 2+ inches of water on top of the grainbed to around one inch as I felt that my higher temp sparge water may have had more time to cool before actually hitting the grain. This, of course, could be complete hogwash.

My LHBS was very reticent to double-grind my grain, and I'm actually glad he was. That ended up not being the problem anyhow. When the tax refund comes in, I think it will be time for my own crankandstein so I can start to buy bulk grain.

Thanks for all the replies. I hope this was helpful to some.
 
There is no such thing as channeling in batch sparging. You infuse the sparge water into a semi-dry grainbed, stir to diffuse the sugar into the water, drain again. Repeat. You drain as soon as it's well stirred.
 
I've run many a column in the lab, and fly sparging is a very similar process. In most cases, the main reason to limit flow is to avoid compacting the column (grain bed) which will slow the flow too much (stuck sparge). That being said, I generally like to run my columns as fast as possible without compacting the bed. If your system can run fast without getting stuck, then I don't think there is much benefit to a slower sparge.

I'm making the assumption that conversion has gone to completion. People often report better efficiency with a slower flow, but I suspect this may largely be the result of extra conversion occurring during the sparge.
 
I'm making the assumption that conversion has gone to completion. People often report better efficiency with a slower flow, but I suspect this may largely be the result of extra conversion occurring during the sparge.

That is an interesting and subtle possibility. Dunno how likely it is to be true, but I like the way you think.
 
When I batch sparge I vorlauf, drain the mash tun as fast as possible, add all the sparge water, stir then let sit for a few minutes to settle, vorlauf then drain quickly.

That is the way I do it, too. My eff is always right around 75%. I could likely bring that up but I don't know if I could do it consistently.
 
So now, my new technique is to lauter slowly. Bobby M says to open up the valve and let her rip, but lautering slowly really made a difference for me and increased my efficiency. I

When referring to a slow sparge speed its usually in the context of fly sparging. When Bobby refers to a fast sparge he is talking about batch sparging.

While some of the posts have been a bit ambiguous it seems like most people here are fly sparging - so Bobby's comments about sparging speed aren't applicable.

If you were fly sparging but were following advice for batch sparging, that would lead to poor results.
 
All my beers are made with the batch sparge technique. Sorry about not being clear. In an effort to increase my eff I had read Bobby M's posts about his batch sparge process and followed alot of his advice. His posts are very informative. But my eff never got higher than 67% into the boiler...so I would buy DME to add to my beers to get a desired OG. I do not own a mill, and the LHBS mill is set at .40 or .41

I have learned that lautering slowly and mashing with 2.0 qts/lb gets me to about 75% eff into the boiler with a crush of .40 - maybe by lautering slowly the grain gets extra time to release their goodness. This combination of techniques has improved my eff into the boiler and I didn't have to buy additional equipment to make it happen. Plus my brew day is just a bit quicker b/c I skip the mash-out and just do one sparge.
 
So yesterday I tried sparging slow, normally I just open the valve all the way and let it dump out, 10minutes max and its empty. So last night I opened the valve less then half and it took about 45min to drain.
My efficiency jumped from 68% to 74% with my last brew when I started using buffer 5.2, This brew last night jumped to 86% eff using the slow sparge and a double batch sparge. I was astounded, and of course now the bohemian pilsner will be like 7.5% alcohol and only the hops for it to be balanced at 5.5%abv. Oh well!
 
So yesterday I tried sparging slow, normally I just open the valve all the way and let it dump out, 10minutes max and its empty. So last night I opened the valve less then half and it took about 45min to drain.
My efficiency jumped from 68% to 74% with my last brew when I started using buffer 5.2, This brew last night jumped to 86% eff using the slow sparge and a double batch sparge. I was astounded, and of course now the bohemian pilsner will be like 7.5% alcohol and only the hops for it to be balanced at 5.5%abv. Oh well!

I had similarly increased my grain bill on my most recent brew when I made BM's Centennial Blonde and had to dilute with two more gallons of water! Blow off tubes were a must.

I'm surprised that you saw that kind of increase with batch sparging. Glad I could help someone else boost their efficiency.
 
Two reasons I can think of. If your crush is coarse, sugars aren't as readily available to the sparge water. If your conversion was not complete in the past, a longer sparge would leave more time for conversion to finish up. This could lead you to attribute the gain to sparge technique when a simple 10 minute extension on the mash time would achieve the same thing. Just thinking out loud.
 
Two reasons I can think of. If your crush is coarse, sugars aren't as readily available to the sparge water. If your conversion was not complete in the past, a longer sparge would leave more time for conversion to finish up. This could lead you to attribute the gain to sparge technique when a simple 10 minute extension on the mash time would achieve the same thing. Just thinking out loud.

But sparge water alone wouldn't be enough to convert the starches. If you've done a mashout, you've frozen the sugar profile of the wort and you'll sparge starches into your mash! I'm thinking that this is really a matter of getting the sugars out of the grain that have already been converted. I did a 90 minute mash and still got pretty abysmal efficiency when I sparged too quickly.
 
I'm a batch sparger also, and have been getting no less than 85% in all my recent brews. I really think people are overthinking it, and the major factor in efficiency is CRUSH.

I have a barley crusher set to about .033, I get a decent amount of flour, not really into wheat beers so never had a stuck sparge, and have always gotten better than 85%.

Before I bought the BC I used my LHBS's mill, they constantly adjusted the gap setting, and I constantly went up and down based on how fine the crush was. It was very obvious, more flour = greater efficiency... more poorly crushed grain = less eff.

Crush crush crush crush crush. That's all I have to say
 
Might the length of sparge have to do with the amount of sweetness remaining after the desired volume has been drawn off? For me that is sometimes a problem. I get decent efficiency, but with some 10lb grain bills I note a gravity of 1.015 or a bit higher in the last runnings. The sugar is converted and available, but it doesn't seem to all rinse out with the 6.5 gallons of water I start the boil with. (Mash with 1.5 qts per lb, split the batch sparge water, do the stirring and waiting, temps are fine.) I know I could run more sparge water through and boil it off, but I suspect there's a way to get more good stuff without.
 
Agreed, crush has to play a greater roll than how fast you sparge. When you wash your dishes, do you let them rinse under a trickle of water for 45 minutes or blast them with as much water as you can as fast as you can?

I am a BIaB brewer and I never miss my OG, usually overshoot as long as my equipment can support the grainbill. i.e. nothing over 12lbs.

This only applies to 5-6 gallon batches though, as I can see the grainbill of 10+ gallon batches would be much less easy to use my BIaB method with - too much soggy grain to be lifting and holding/draining without a pulley system to lift it all up and out of the MT to drain.
 
Agreed, crush has to play a greater roll than how fast you sparge. When you wash your dishes, do you let them rinse under a trickle of water for 45 minutes or blast them with as much water as you can as fast as you can?

This is true for Batch sparging but not for fly sparging. Crush is important but a fast fly sparge will not get you the same numbers as a slow fly sparge.


I think we need to clarify which methods we are talking about. :)
 
Then why even fly sparge when a batch sparge accomplishes the same thing in an exponentially quicker timeframe? Is this kind of like the debate between the decoction mashing method and single infusion mashing? Both do the same thing essentially, but one goes much quicker?

Its kind of ironic how we are debating "efficiency" and using a very efficient (quick) way to get good efficiency and an inefficient and more lengthy process to get the same efficiency.

Tell me if I am way off base here. I'm still pretty new to all of this.
 
Then why even fly sparge when a batch sparge accomplishes the same thing in an exponentially quicker timeframe? Is this kind of like the debate between the decoction mashing method and single infusion mashing? Both do the same thing essentially, but one goes much quicker?

Its kind of ironic how we are debating "efficiency" and using a very efficient (quick) way to get good efficiency and an inefficient and more lengthy process to get the same efficiency.

Tell me if I am way off base here. I'm still pretty new to all of this.

Such a good point! This is why the debate is still on.
There's so many variables with crush, temperatures, grain type & freshness (and so many others with water chemistry) that it's probably impossible to debate it in the first place.

My .02 cents
 
Then why even fly sparge when a batch sparge accomplishes the same thing in an exponentially quicker timeframe? Is this kind of like the debate between the decoction mashing method and single infusion mashing? Both do the same thing essentially, but one goes much quicker?

Its kind of ironic how we are debating "efficiency" and using a very efficient (quick) way to get good efficiency and an inefficient and more lengthy process to get the same efficiency.

Tell me if I am way off base here. I'm still pretty new to all of this.

Both Boerderij_Kabouter and I use a fast fly-sparge technique with no apparent affect on efficiency. It's a matter of equipment and technique. I can get 14.5 gallons into the kettle in 30 minutes with 90% efficiency.
 
But sparge water alone wouldn't be enough to convert the starches. If you've done a mashout, you've frozen the sugar profile of the wort and you'll sparge starches into your mash! I'm thinking that this is really a matter of getting the sugars out of the grain that have already been converted. I did a 90 minute mash and still got pretty abysmal efficiency when I sparged too quickly.

Perhaps Kaiser will chime I'm on his thoughts on enzyme stability, and I agree with what he says based on my working with enzymes in a lab. The enzymes do not instantly stop working, it takes time. Kaiser says there is still conversion going on after hitting mash out temps. I know for a number of enzymes that I use in the lab (not as stable as the amylases) it takes anywhere from 5-15 min at 212 F to totally stop all of the activity.

To set the wort profile, it isn't instantaneous when you hit 168F, it is going to take at least 15 min., even then I bet you'll still have some amylase activity.

Back to the fast flow fly sparge. In running columns you can run them too slow. This will result in broad peaks and also takes more solvent. The slower the sparge, the more water it will take to reach the same ending gravity points before stopping the sparge.
 
Perhaps Kaiser will chime I'm on his thoughts on enzyme stability, and I agree with what he says based on my working with enzymes in a lab. The enzymes do not instantly stop working, it takes time. Kaiser says there is still conversion going on after hitting mash out temps. I know for a number of enzymes that I use in the lab (not as stable as the amylases) it takes anywhere from 5-15 min at 212 F to totally stop all of the activity.

The commonly cited figures are 20+ minutes at 170+ temps to denature enzymes.
 
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