strong grapefruit flavor, whats the cause?

So about 3 weeks ago I brewed my first attempt at a California Common. I know that secondary fermentation isn't suggested but I needed my primary for another brew so I transfered it at 10 days. Whenever I do a transfer I always like to have a little taste just because I can't help myself. When I tasted it I noticed probably the strongest most clearly defined grapefruit flavor I've ever had in a beer. It wasn't bad, just not what I had planned in my mind and I'm trying to figure out the cause. Here's the recipe.

6.6lbs dme
1lb Munich
1lb Crystal
1oz northern brewer 60 mins
1oz cluster 30 min
1oz northern brewer 5 mins
Wyeast 2112

I fermented at 57 for 7 days and checked the gravity. It was still around 1.02 and it seemed pretty close to stalling so I brought it up to 64. 3 days later I transferred it and tasted it and kept it at 64.

So did I under pitch my yeast?. Could 3 days at 64 change it that much? Or should I expect this based on my recipe? Any thoughts would be helpful, thanks!

After the 3 days at 64, was the gravity reading the same as before you moved it? If it was still lowering, you should have left it 'till the gravity was stable over a 2-3 day window. Did you make a starter? Properly aerate / add O2 to the wort before you pitched? I'm interested in this kit myself and am just curious how it's going on your end.

The grapefruit flavor is most likely from your hops. Northern Brewer and Cluster aren't usually described as having a grapefruit flavor though. This description is usually ascribed to hops like Cascade. The combination of the two hops could possibly give you that perceived flavor.

This is unlikely, but Brett infections can sometimes come across as fruity.

I made an all Brett B IIPA and it tasted almost exactly like Tropicana grapefruit juice. I know it wasn't just the hops either because the decant off the starter tasted like grapefruit juice.

eddavis80 - I'm pretty sure It was well aerated, no I didn't make a starter just used a smack pack, it was a bit of an unexpected brew day/I was lazy. I know that it can stress the yeast out but I figured that might just cause it to stall. fg was 1.014-1.015, I'm terrible at reading these things so its about 4.5% abv. so it did ferment a bit more, but again 64 degrees is well within the range tolerance for the yeast strain.

the grapefruit flavor is still there but if you're right Flars and it is the hops then it should settle down once it's conditioned. it already has quite a bit.

All in all the beer seems fairly clear. Hops seem very present but not overwhelming so I think it'll turn out nice. I'll post an Update in a couple of weeks when its conditioned a bit better.

If anyone was actually interested I cracked a beer after 8 days in the bottle because I'm impatient and more importantly, because I was out of beer.

Even after 8 days Carbination seemed pretty good, head was good and held for a while, slightly off white colour. The Beer itself turned out pretty damn good. The grapefruit intensity is almost completely gone, just some nice citrus undertones. Bitterness is perfect I think, I'll for sure make this again. I'm not sure if its Northern brewer/cluster combo but it almost tastes like some single beers i've made iwth Nugget, but way smoother.

My only concern is that if it's carbonating nicely at 8 days I over primed it and may end up with beer bombs at 3 weeks.

I'm extremely critical of my brews and somehow am never completely satisfied with the final product, but I think this one is amazing. I highly recommend it to anyone else who's interested.

Very good that it came out for you! I did a batch using Citra hops and at bottling I thought I might have over done it with the hops at flame out but after a week in the bottle I poured one up and it had mellowed out some. It should only be better with a few more weeks of aging (I hope).

How do you like the Wyeast 2112? Thinking of using it with some of the lager kits as it has a bit of a higher fermentation temperature than a standard lager yeast.

First time using 2112. Deffinately gives off more ale characteristics than typical lager yeast but that's expected I thing. All in all it just has a lot of character

Interested in both Cali Common and 2112 - sounds like they worked magic together. Enjoy the brews!

Perhaps your hops were mislabeled? As far as bottle bombs go, what was your gravity at bottling and how much priming sugar/gallon did you use?
I've used the White labs SF lager with good results. Online posts suggest the 2112 is somewhat slow to finish. Cali common will benefit from cold conditioning so if you have enough carbonation and a spare refrigerator, try putting away whatever you can keep yourself from drinking and see if you like it better after a month below 50 degrees.
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