Problems with a CITRA IPA

Citra hops are high in the compound 4-mercapto-4-methylpentan-2-one (commonly termed 4MMP). Some people's palates perceive 4MMP as having a flavor/aroma of cat pee. Any chance this is the weird flavor you mention?

Why you would perceive your first batch as being tropical fruit forward and the second batch as being different is something I am uncertain about. Maybe the Citra hops you used for the second batch had larger amounts of 4MMP in them?

Cheers!

 

The yeast giveth and the yeast taketh away . . . Here's a detailed read on diacetyl and what's going on in your fermentor, should answer many of your questions.

My other suggestion is to slow down your process. You are drinking your beer at the 4 week mark and wondering why it has off flavors. I find a couple more weeks of conditioning makes a world of difference. So I suggest you rein in your horses . . .

 

As others mentioned, ferment warmer. 65-69 is the sweet spot I've found.

If using S05 you'll get much more "apricot" than Wyeast and White Labs. Don't know why but I've always noticed more apricot in the 05.

I'd let it sit in the primary for a week and then dry hop to your taste for a week. Also, if you're bottling I do think the character will change over time as the beer conditions.

If you're impatient (like I was when bottling) set a sixer of your beer in the garage or on top of the water heater (just make sure it gets warm and not hot). You can essentially "speed up time" by conditioning in a warmer environment.

I always did that to get an initial taste and then let the rest of the batch condition over time.

The yeast will clean up the diacetyl in the bottle so aging longer probably will help.

 

Another thing to consider is water chemistry, and water source. I know my house water source gets switched when there is a drought, and the two sources are fairly different. Along with that is pH. Did you measure the mash pH? I did a batch of heady topper clone twice, about 2 months apart. Identical except for ferm temps and pH. Worlds different end result. The higher pH (5.5 vs 5.2 IIRC) version had a muted malty blah taste compared.

 

Awesome! Good for you, and good luck. I would say fermentation temperature and yeast health (starter, O2) are the most important thing for going from good to great. Water chemistry has really been helping me fine tune some things as well.