Too much sparge water negative side effects

[Ozarks Mountain Brewery]

I'm sure you have gotten your answer to your satisfaction already...but rereading most this whole thread I just want to calcify that I am one of those you have probably read in other threads that do exactly this.." Keep sparging till I have my correct boil volume"

Just to be clear that does not mean I toss in water willy-nilly and leave any unused wort in my MLT...what is meant is that if I'm a gallon short I would run exactly 1 gallon more water through the grains. That's all no more no less. And in my case readings have never been to low. Others or YMMV

I agree, if anyone thinks that just running clear water over the grain till you get your correct volume is what they do then the recipe is wrong, most of the time my sparge still has sugar in it even when my volume is met, as a matter of fact I can make a second runnings making a 1 or 2 gallon beer most brew days so over sparging that extra gallon just adds more sugar "not plain water"

 

[Ozarks Mountain Brewery]

at the same time I think its very bad to barely have enough sparge water if using pumps because you starve the pump and as its gasping for more wort your adding oxygen into the wort before the boil. We don't need that at 170 degrees, Ive made that mistake several times and for that reason alone I always have more sparge water than I need just to keep the pump sufficiently flowing then I discard the rest when I hit my starting boil volume

 

[smyrnaquince]

I recently brewed a Mild. 1.029 pre-boil. 1.036 OG. I did a double sparge, but didn't measure the SG if the final sparge. Maybe I should have.

So, any off flavors?

I just had one. Nothing off that I noticed.

Let me update that. I had entered this mild in to a competition to get judges' comments. Comments pertinent to this discussion:

Judge 1:

• ...perhaps a bit acidc
• Is this a second-runnings beer? Perhaps a touch over-extracted if so.

Judge 2:

• ...slight phenol/plastic
• ...shows some astringency with an overly dry finish.

 

[Yooper]

Let me update that. I had entered this mild in to a competition to get judges' comments. Comments pertinent to this discussion:

Judge 1:

• ...perhaps a bit acidc
• Is this a second-runnings beer? Perhaps a touch over-extracted if so.

Judge 2:

• ...slight phenol/plastic
• ...shows some astringency with an overly dry finish.

The descriptions of astringency and a judge mentioning over-extraction are classic signs of oversparging.

phenol/plastic is more related to chlorophenols (chlorine), though.

 

[Stillraining]

at the same time I think its very bad to barely have enough sparge water if using pumps because you starve the pump and as its gasping for more wort your adding oxygen into the wort before the boil. We don't need that at 170 degrees, Ive made that mistake several times and for that reason alone I always have more sparge water than I need just to keep the pump sufficiently flowing then I discard the rest when I hit my starting boil volume

But I Have a hunch your recipe grist's are sized to account for that extra wort/sparge water volume loss needed for your system...No?

 

[doug293cz]

It is possible according to my simulations. Using a 6 lb grain bill with 7.3 gal of total brewing water (6.5 gal pre-boil vol), and doing a double batch sparge with equal volumes for all three run offs, gives me 2˚P (1.008) for the final run off. This is admittedly an extreme example, Pre-boil gravity is 7.9˚P, and OG is 9.3 (5.5 gal.)

Brew on

If you were brewing and English Mild (just one style example) which has an OG range of 1.030 - 1.038, and your standard process was a 2X batch sparge (for high efficiency.) The simulation I did had a pre-boil SG of 1.0315 and an OG of 1.037.

Brew on

I recently brewed a Mild. 1.029 pre-boil. 1.036 OG. I did a double sparge, but didn't measure the SG if the final sparge. Maybe I should have.

Let me update that. I had entered this mild in to a competition to get judges' comments. Comments pertinent to this discussion:

Judge 1:

• ...perhaps a bit acidc
• Is this a second-runnings beer? Perhaps a touch over-extracted if so.

Judge 2:

• ...slight phenol/plastic
• ...shows some astringency with an overly dry finish.

The descriptions of astringency and a judge mentioning over-extraction are classic signs of oversparging.

phenol/plastic is more related to chlorophenols (chlorine), though.

So, now we have a real life example of an over sparge when batch sparging. @smyrnaquince 's pre-boil SG was slightly lower than for my simulation, which had a final runnings SG of 2˚P or 1.008, so the real batch's final runnings would likely have been less than 2˚P.

From this we can work out a guideline for when to avoid double batch sparging in order to avoid over sparging.

To keep last sparge runnings SG greater than 3˚P (1.012), don't do a double batch sparge for pre-boil SG targets lower than 1.039 (OG ~ 1.048)

To keep last sparge runnings SG greater than 2.5˚P (1.010), don't do a double batch sparge for pre-boil SG targets lower than 1.036 (OG ~ 1.044)​

@smyrnaquince : Do you know the alkalinity of your sparge water, and did you acidify the sparge water?

Brew on

 

[smyrnaquince]

I used BrunWater to adjust my tap water. I dialed in a target sparge pH of 6.0. It had me add 0.9 ml of lactic acid to my 3.12 gallons of sparge water (split into two 1.56-gallon sparges). The total sparge volume is low because this was a 3 gallon batch (into the fermenter).

 

[skokott]

"Just to be clear that does not mean I toss in water willy-nilly and leave any unused wort in my MLT...what is meant is that if I'm a gallon short I would run exactly 1 gallon more water through the grains. That's all no more no less. And in my case readings have never been to low. Others or YMMV"

Ok got it. I guess I'm a bit slow. lol. Thanks.

 

[Ozarks Mountain Brewery]

But I Have a hunch your recipe grist's are sized to account for that extra wort/sparge water volume loss needed for your system...No?

correct, you have looses in a lot more places than people think, you have to account for those or you will always end up short

 

[Denny]

For a "normal" gravity beer, do I run the chance of oversparging if I batch sparge in two sparges (half the total sparge volume each time) instead of in one sparge? Or is oversparging only a concern with fly sparging?

I typically mash at 1.5 qts/lb, then do two (half-volume) batch sparges to get to my final pre-boil volume. Now you have me wondering if i should be doing a single (full-volume) sparge instead, at the cost of (just) a couple of percentage points of extraction efficiency. As an example, the last brew that I took a final runnings SG measurement on came in at 1.013 for the second sparge, with the pre-boil (combined mash, sparge 1, and sparge 2) SG at 1.036. SG 1.013 = 3.3 brix for that last sparge, which is getting into that 3-4 brix danger zone.

The risk of oversparguing is very slight, assuming you use the same amount of water as you would for a single sparge addition. But unless your mash tun isn't big enough to hold all the sparge water at once, you gain nothing by doing it and waste time.

 

[Denny]

So, now we have a real life example of an over sparge when batch sparging. @smyrnaquince 's pre-boil SG was slightly lower than for my simulation, which had a final runnings SG of 2˚P or 1.008, so the real batch's final runnings would likely have been less than 2˚P.

From this we can work out a guideline for when to avoid double batch sparging in order to avoid over sparging.

To keep last sparge runnings SG greater than 3˚P (1.012), don't do a double batch sparge for pre-boil SG targets lower than 1.039 (OG ~ 1.048)

To keep last sparge runnings SG greater than 2.5˚P (1.010), don't do a double batch sparge for pre-boil SG targets lower than 1.036 (OG ~ 1.044)​

@smyrnaquince : Do you know the alkalinity of your sparge water, and did you acidify the sparge water?

Brew on

OR....never do a double batch sparge unless your mash tun is too small to hold all the sparge water at once.

 

[doug293cz]

The risk of oversparguing is very slight, assuming you use the same amount of water as you would for a single sparge addition. But unless your mash tun isn't big enough to hold all the sparge water at once, you gain nothing by doing it and waste time.

I disagree. There is a quantifiable benefit to doing more than one sparge step. You do get diminishing returns with each additional sparge. The chart below shows the differences for the case of equal run offs for first runnings and each of the sparges.



Kai Troester gets similar results as reported here. He covers smaller grain bills in his chart than do I.

Whether the efficiency gain is worth the extra effort is a separate question, that each brewer gets to decide for themselves.

Brew on

 

[Denny]

I have batch sparged 501 batches of beer now. I have tested multiple sparges many, many times. Using 2 sparges results in so little efficiency increase in the real world that it's virtually unmeasurable and what I consider to be a waste of my time. I encourage people who are doing multiple sparges to try it with only one to see what the difference is. And if there IS a large difference, it's indicative of a problem somewhere in your process. You may want to solve that problem.

 

[Stillraining]

Thanks for that Doug....I was going to disagree too but thought who am I to do that with this guy... Im Not a math guru or beer guru as you guys are..I'm just a pragmatist.


Drinking = fun
Cleaning=boring
Bottling/ Keging= boring
Fermentation = boring
Boiling = boring
Batch Sparging/Vorluf ( 1st time ) =fun
Mashing =fun
Building recipe=fun

Score now tied at 4-4

Batch sparge and Vorluf ( 2nd time) =fun

Puts me in the winners circle mentally on brew day every time...No problem with process on my end. ......I understand this is not scientific at all... and YMOV.....that's OK...Peace, Love man!

Carry on.