Batch Sparge and Ph level

I'm a batch sparge person and lately have had remarkable efficiency (mid 80's).  I'm a little suspicious of this to be honest.  I'm wondering if I might be getting things I shouldn't.  For example, my recent bitter has a tea taste to it.  From reading and some of the answers given on the other board I'm wondering if its possible the ph of the mash is falling to much toward the end of my sparge rounds.  I usually employ three runnings.  The first runnings, the first batch sparge then 2nd running then the 2nd batch sparge followed obviously by the 3rd runnings.  I found this method to be great for efficiency but is there a dark side that maybe I'm not aware of?   

I know most sources say that ph isn't normally a concern when batch sparging but I'm wondering why not and is it realistic to think my wort might become too acidic?

The guideline I've read about "when to stop sparging" is when the gravity of the last runnings hits 1.010.  The other caution is not to sparge with too-alkaline water (above 6.0).  These two issues can lead to stripping harsh tannins from the husks, which leads to potential astringency.  I could see how a very minor atringency might "taste like tea" rather than give you that biting, drying sensation across the gums that major atringency might create. 

I 'think' most fly spargers sparge until they hit 1.010, so they're more aware of that number than batch spargers.  I 'think' most batch spargers usually do two batches and their final runnings are safely above 1.010 and so they worry less about it.  Since you are flooding the grains three times (very efficiently) you may just be reaching that threshold where you're getting a tiny amount of tannins from the husks. 

A refractometer is great for monitoring gravity during the sparge (ebay is the place to buy.)  A pH meter or strips may be enough to determine if your water's pH is too high.  Since it is a slight tea taste, it seems more logical that it may be the over-sparging during the final minutes.  If it was the water's pH, then it seems like the entire sparge would be at risk and therefore you'd detect a lot more evil than you do. 

Hope that helps.  Is your lauter tun small, and that is what requires three batches to get the volume you want? 

Maltlicker,

Actually my MLT is quite large, I could easily do a 10 gallon batch but to this point I've only done 5.5 to 6 gallon batches.  I usually decoct some of the mash liquor and bring it to a boil to get the mash to the right mash out temp then let it run.  Then I break up the batch spage rounds.  I've been doing three runnings because it seems like you'll get greater efficiency and we'll to be frank I have.  I think the analogy goes back to the same volume of water cleaning a dirty glass.  will the glass get more clean by rinsing it more with one big volume or by breaking up that volume and rinsing it twice.  I seem to remember reading somewhere that smaller volume with more rinsing will get the glass cleaner, ergo the more batch sparge rounds.  I'm wondering now if I should just put the first batch sparge round in and let it run.  I might sacrafice some efficiency but its worth it to make good beer.

Of course, I might be removing the beer from the primary too soon as well as getting the mash too hot at the end with sparge water thats too hot?  which variable is it?

Hmmm, your original two posts cited a slight tea taste, and I went toward a minor astringency.  Someone else said green leaves = acetaldehyde.   The signal for acetaldehyde is usually "fresh cut green apples" but who knows, since you said it was very slight?  So first we'd have to correctly ID the off-flavor. 

I backtrack b/c you also mentioned time on primary possibly being cut short.  Acetaldehyde is a yeast by-product and is usually cleaned up by the yeast if allowed to do so.  If time on the yeast does not solve it, aeration and yeast nutrients might need boosting.  Also aging the beer longer before consumption helps.

Astringency typically comes from grain/sparge practices, and solutions include don't over crush, over sparge, sparge > 170F, and don't boil.  I've always wondered about decoction boiling and astringency, but it obviously works if done properly. 

I'd recommend you invite over friends with decent tastebuds and try to first get at the true root cause before you change a working, efficient sparge process.  If it is minor acetaldehyde, then extending the primary ferm and waiting an extra week to drink may solve everything. 

MaltLicker,

It is definitley a tea taste (had my wife try it just to be sure).  Its not puckering or leafy or anything, it taste like tea. Not horrible but it shouldn't be there.  I'll finish the keg because it is slight.  Like I said its an of flavor not a keg killer. 

I've been doing some reading too and I think the first thing to do is increase the time on the yeast.  Be very careful with my sparge water temp and mash out temp.  Maybe shoot for 166 instead of 168 just to be on the safe side?  I'll try those things first and see what happens.  I'd hate to give back some efficiency pts but I will if I have to. 

On a side note, This isn't really a new problem, I've been getting this in my beer off and on for awhile, usually with my lighter pale ales.  Specifically, its been showing up long before I refined my process to be as efficient as it is now.  Prior to the decocotion of the mash liquor, prior to the finer grind, prior to the >80% efficiency etc.  So, I'm thinking that the root isn't in the brew day process so much as it is in the quick removal of the beer off the yeast.

But then again, I just can't shake the idea that in my quest for better and better efficiency I've started to employ bad practices.  Mainly, over sparging or perhaps crushing the grain too much.  This is a tough one because I've gotten really proud of my process and obviously the high efficiency but if I'm getting too much of a good thing, which is giving me bad things then I guess some other things will need to change  :-\

Wildrover said:

...I've been getting this in my beer off and on for awhile, usually with my lighter pale ales.

Click to expand...

There's less in a pale ale to hide things.  If you dry-hop the pale ales, and it's a grassy tea leaves taste, that might be part of it.  Sounds like you're on your way to fixing it. 

I hope you're right