I'm relatively new to homebrewing (currently on my 4th batch) and have noticed a peculiar aftertaste in some of my beers. The first time I brewed a 5 gallon batch, I brewed a malt extract/specialty grain recipe from my local homebrew store with the following ingredients:
6 lbs Light Dry Malt Extract
.50 lbs 80L Crystal Malt Extract
.75 lbs Aromatic (Grain)
1 oz Perle Hops (Bittering)
1 oz Willamette Hops (Bittering)
1 oz Fuggle Hops (Flavor)
1 oz Cascade Hops (Flavor)
1 vial of WLP001 California Ale Yeast
I started with 3 gallons of water (Arrowhead Mountain Spring Water) in my pot. The specialty grains were steeped for 30 mins at 155°F (I was turning the stove on/off to keep this temp relatively close...it did briefly get up above 170°F for a brief amount of time, which I've read elsewhere is the temperature at which various other off-flavors can get extracted from the specialty grain). After the malt was added, I added the Willamette hops. 30 mins later I added the Fuggle, and then 15 mins later I added the Cascade and allowed it to boil for another 15 mins. I then took the wort and added it to 2.5 gallons of cold water in my fermenter. I then covered this fermenter (with air lock) and put it in an ice batch (I currently don't have a wort chiller). My sink isn't very deep, so the ice batch wasn't very effective. At this same time I took the yeast out of the fridge to let it activate (the vial instructions said to let it sit out for 3-6 hours). Well, it ended up taking about 10 hours for the wort to cool down to 75°F.
I pitched the yeast and then about 4-5 days later, I transferred it to a secondary. The temperature during most of the fermentation process hovered around 72 to 75°F. After about another 10 days, I took my final gravity reading and then bottled. After letting the beer bottle condition for about a week, I tried one. It tasted great! There wasn't any off-taste at this point. However, after about another week, the beer started to develop a weird "twangy" aftertaste. I can't put my finger exactly on how to describe the taste except that it tastes a little harsh and has sort of an earthy component.
From some research I've done online, I've heard that the harshness could be attributed to a high fermentation temperature. Is the temperature range I described above a possible contributor? I'm also concerned that the length of the wort cool down after boiling opened up the possibility of bacterial infection. Would bacteria give beer the taste I've described? Another thing I'm concerned about is that the yeast was sitting out longer than the directions stated it should have. Could that have an impact? I also know from doing a little research now that my water probably should have been a little harder. Would soft water cause any of these off-flavors?
I'm new to homebrewing so any advice that any of you could give me is really appreciated!