I Seek Thy Judgement... PLEASE help me out...

[TrickyDick]

Oh, one thing that does come to mind. How have your mash temps been throughout the mash and what is your mash tun?
Metal tun and small batches might suffer from losing heat during the mash, and smaller amount of grain, such as in a half batch 2.5 gal, would make it worse.
I know your thermo was recently calibrated, but not sure if you had a brew day with the fixed or calibrated thermo. I use three thermos . One is the thermocouple in my rig, the other the bimetallic thermo on the mash tun, and the other is a handheld digital thermapen.... Pricey but accurate and FAST.

If you mash in and add heat with direct heat on a metal mash run without stirring, you could overheat a part of the mash and denature the enzymes accidentally, but that wouldn't necessarily hurt your gravity readings, just the fermentabiity. Are you making the temp corrections on your hydrometer when measuring HOT wort? I think most are cal for 60 degrees. Beer smith can correct this too. Boiling water could potentially overshoot temp in a small mash if your measurements for volume and infusion temp are off. Sounds like your using beer smith which I Think can make these calculations painless.

TD

 

[ViperMan]

Ah, okay - that makes sense. Why does this silly hobby have so many names for the same thing??

 

[rklinck]

Ah, okay - that makes sense. Why does this silly hobby have so many names for the same thing??

To make those "in the know" seem smarter than others.

 

[ViperMan]

UPDATE:

So first off I want to thank EVERYONE who's posted here with input and suggestions, questions, etc.

This past weekend I had a big beer-drinking party. It kinda floundered in the attendance category, but two of the people who DID show up were pretty experienced brewers - one who's been working in the 25-gallon batch capacity for some time now. He had several suggestions and was able to look at my equipment, supplies, etc, and made some really good suggestions.

The next day I brewed a medium-body ale - it was a relatively light base-malt, but approaching amber territory, about 5.6 ABV if I recall.

I made several changes from my usual procedure.

1) I used city water, treated with campden tablets the night before to remove chlorine
2) I used some 5.2 stabilizer treatment - .3 tbls to be precise
3) I step-mashed, first at 140 degrees. My second step to 154 didn't quite work (stupid thermometer is screwed up again) so I had to sorta decoct my way to 154.

The results were noticeable by the first batch-sparge. The runnings were barely sweet, and MUCH lighter in color than the first runnings. By the second batch, the runnings barely had any flavor whatsoever.

Total observed efficiency was 83%. I felt like a proud father at a graduation ceremony... Of course, I broke the cardinal rule of science by attempting three variables at once, so I have no idea which change had the most impact. I might try my next beer without the 5.2 as I think my beers are getting costly enough as it is. I do like the cost savings with tap water though.

The true test will come with my next stout, to be brewed probably next week. I need to see if I can overcome the effect of the darker grains on my mash ph and still get good efficiency. If I can pass that test, I'll push myself further with another heavy grain bill, like a dopplebock or double stout.

Thanks again for everyone's input.

 

[rklinck]

Good to hear that things got better. A couple of thoughts.

First, I recently had my efficiency drop significantly for a single batch (from the mid-80s to about 70 percent). I am pretty sure that the reason was that the SS coil (I have a set up like yours) was displaced and got pulled up significantly when I was stirring the mash. This was the first time this happened (and I'm thinking it was because I added the water in small batches rather than adding the majority of it before stirring). I tried my best to push the coil down, but there was no way to do that with the mash at 150 degrees. I'm not sure if part of your problem might be that you are pulling up the coil while you stir.

Second, if you are worried about the darker grains messing with the pH, add them late. I recently read Gordon Strong's book, and he suggests adding roasted grains at vorlauf. I did that with my last stout. The beer had plenty of time to pick up the flavors and color from the roasted malt (and my wife has insisted that I brew my stouts with that exact recipe from now on). Considering that you are batch sparging, maybe add the roasted grains with 10 minutes left in the mash. By that point, most of the conversion should be complete.

 

[ViperMan]

Good to hear that things got better. A couple of thoughts.

First, I recently had my efficiency drop significantly for a single batch (from the mid-80s to about 70 percent). I am pretty sure that the reason was that the SS coil (I have a set up like yours) was displaced and got pulled up significantly when I was stirring the mash. This was the first time this happened (and I'm thinking it was because I added the water in small batches rather than adding the majority of it before stirring). I tried my best to push the coil down, but there was no way to do that with the mash at 150 degrees. I'm not sure if part of your problem might be that you are pulling up the coil while you stir.

Second, if you are worried about the darker grains messing with the pH, add them late. I recently read Gordon Strong's book, and he suggests adding roasted grains at vorlauf. I did that with my last stout. The beer had plenty of time to pick up the flavors and color from the roasted malt (and my wife has insisted that I brew my stouts with that exact recipe from now on). Considering that you are batch sparging, maybe add the roasted grains with 10 minutes left in the mash. By that point, most of the conversion should be complete.

Thanks for the comments. I make sure to stir either above the false bottom or inside the ring itself. Also I make sure to get the mash REALLY moving and then press the ring down while the grains are suspended. My poor efficiency has been quite consistent (as in, consistently poor) for several batches though, so I don't think the false bottom has much to do with it.

As for the dark grains, I like your idea. The other thing Strong suggested (I have his book and also saw the Beersmith discussion on the same topic) was steeping the dark grains separately and adding that wort to the boil kettle or even the secondary. I intentionally had my LHBS separate out the dark grains for this batch for either of these suggestions. (I like your suggestion better as it cuts out excess calculations, steps, and pots!)

I think I'm going to brew my stout this Friday after work (I have the house to myself for the weekend!) so we'll see how I fare.