Possible infection or yeast problem?

[d2005]

My friend and I have been brewing for about 4 years now and it looks like we finally have our first undrinkable beer.

Very simple ingredients that we have used several times:
7.5lbs of pilsner malt
8 oz of crystal malt
Typical hop distribution ~30 ibu
Normal single step mash (i can do into details if really neccesary)

The big question mark in all of this is the yorkshire square yeast from white labs.

We temp controlled the fermentation in a stainless fermenter. It was kept at 64F or so.

It started a normal profile, but then wouldn't stop. It even sped up a few times after 3 weeks! The beer is VERY dry and it has a medicinal quality to it. Not to mention it is quite cloudy, but there was no sign of infection on the surface of the beer.

I've read on many forums about this particular yeast and some people respond that it is great. White labs descibes it as "malt driven".

But it's interesting how MANY people have responded that this "platinum strain" performed exactly how it did for us; very dry, very tart, medicine flavors. I've had samual smiths before in the UK and while it tasts "similar" to what we got out of our batch, but not this strong. This particular brew is pretty much undrinkable.

Anyone else have any experience with this strain of yeast?

Could this be a secondary infection or just a bad sample of yeast?

Thanks for the help!

 

[ArcaneXor]

I used this yeast for a Northern English Brown, and didn't care for at all. It was extremely ester-driven, and the beer tasted quite unbalanced. It was neither dry, tart or medicinal though. At what temperature did you ferment?

 

[d2005]

We fermented at about 64F.

Yeah the more i read about this yeast the more I am starting to wonder if its just not very consistent.

On several forums people have reported exactly what I have. Far too dry, tart, lots of esters, and medicine flavors. I like a good ester beer, but not when it is champagne dry.

Oh well. It was within a month of it's expiration date. Not to mention that I bought it from a new brewing store it town. Who knows if those jokers stored it properly. I live in AZ and proper yeast storage is a huge deal here.