Weird Taste

I recently brewed a Pumpkin Brown Ale based on the ThunderStruck Pumpkin recipe found here in the forums. This was was my second all grain beer and I had very low efficiency of around 50%.

The beer has been in the bottles for over 4 weeks and I cracked the first one a few days ago and while it has a nice pumpkin spice aroma and color is good, the beer has a charcoal like aftertaste. My son tried one and said the same thing. The third bottle I opened after pouring in the glass, I added a pinch of salt to the beer, and this one had no aftertaste. So until I try a few more, I am not sure if some of bottles are off, or all are, but somehow the salt offset it.

Ingredients
Amt Name Type # %/IBU
1 lbs 3.8 oz Rice Hulls (0.0 SRM) 8.9 %
8 lbs Pale Malt (2 Row) 57.2 %
2 lbs Caramel Malt - 60L 14.3 %
1 lbs 4.0 oz Biscuit Malt 4 8.9 %
8.0 oz Wheat, Flaked 5 3.6 %
59.00 oz Pumpkin (Mash 0.0 mins)
1 lbs Amber Dry Extract (12.5 SRM) 7.1 %
1.00 oz Goldings, East Kent [4.50 %] - Boil 60.0 min 13.7 IBUs
1.00 Items Whirlfloc Tablet (Boil 15.0 mins) F
1.0 pkg English Ale (White Labs #WLP002)
0.50 tsp Ginger Root (Secondary 14.0 days)
1.00 tbsp Pumpkin Pie Spice (Secondary 14.0 days)

The spices were added in a "tea" water was boiled then spices were steeped.

OG should have been 1.056 per BeerSmith, but I only hit 1.047, FG was 1.019.

Any ideas what could cause the charcoal taste?

My sanitation steps were the same as always. One Step to clean then Star-San. One thing I am wondering about though...after sanitizing bottles with Star-San, some of the bottles may have still had a little water in them when I went to fill them. I drained most of them completely, but know that maybe 10% I forgot to completely drain.

This is my 5th brew after getting back into brewing after 15 years or so and the first that had an issue, so it's driving me nuts!

Sounds like it might be tannins, how hot did you sparge? or possibly over sparge?

Did you use filtered water from your own home water filter? Lots of home water filters use charcoal elements in their filters, and when the filter needs replaced it will often give off a charcoal taste.

It's definitely not the StarSan. Did your beer come in contact with anything unusual during mashing/boiling/fermenting? I reccomend checking your waters Ph next time, and it's Calcium/Chloride/Sulfate content if possible to make sure everything is where it should be.

I did not used filtered water. I brewed 100% outside for the first time...water was from an outside faucet using a potable water hose. I sparged at 170, using whatever BeerSmith told me, don't have in front of me right now. Could it be wild yeast? It was slightly breezy that day and our yard is surrounded by trees. During fermentation, I did have a yeast blowout while I was away for 2 days. The yeast blew up into the fermentation lock. I cleaned and sanitized it as soon as I got home. I used PH 5.2 stabilizer and also checked with Ph strips and Ph was around 5.4, but I know those strips are not the best.

I'm so bummed because I was so looking forward to homemade pumpkin ale. But I already have 6 29 oz cans of Libby's sitting in my pantry waiting for the next time I want to give it a go!

It's hard to tell, as you probably know there are infinite variables in brewing, is it undrinkable? You could try distilling it, although that may or may not be illegal where you live.

Slightly scorched wort perhaps?

I was thinking scorched wort too, because it was the first time using a high powered banjo burner...but opened two more bottles yesterday and they were both fine. So the score now is 3 bottles tasted fine, 2 had the charcoal aftertaste. So the problem has to be something with a few, or hopefully just the first two, bottles. Even the charcoal taste ones are drinkable once you get past the shock!