Phenolic notes in a Premium Bitter (WLP002)

[Ceejay]

I tried a bottle of my 8B Normal Beer today and I tasted distinct clove phenolics, very similar to a half decent hefeweizen. It is actually delicious, and I'd brew it like this again but clearly not planned! Question is, why is it there?

Things I think could have contributed:

It's only 5 days into cold conditioning after 2 weeks warm, so is just "green" and it will go away.
Temperature dropped from 20C to 15C on day 2 of the ferment due to a really cold day. Moved it and brought it back up to 20C - maybe this has caused it to go a bit "Belgian"?
I pitched a 1.5L starter from a vial of WLP002, maybe a tad under pitched (OG 1044)

Other things that make me think it's not wild yeast or another infection:

Carb level is fine, not gushing or anything
Still has the desired amount of body, 1010 FG is holding steady.
I'm very fastidious about sanitation, always using OXY/Videne on everything cold side
There's no physical "funk" in the beer.
Could be too early to tell if it's an infection though...And it does have a bit of a haze (which is probably chill haze)

Any ideas? Anyone else noticed anything like this when using WLP001?

 

[robsan77]

A little residual cleaning fluid or chlorine in the.water can cause that. Did you use campden tablets?

 

[Ceejay]

Yep, 1 campden tab per 23L . Bottles and fermenter get rinsed a couple of times with water before sanitizing too. Having another pint now, and it's not quite as clovey as before; this pint is cooler though, so I'd expect that. It's definitely something I like in the beer but I imagine it'd get dinged in a competition!

 

[Ceejay]

I've been researching this a bit on the internet.

Seems one source of the clove phenol flavour is caused by 4-vinyl guaiacol which is formed when certain yeasts produce the enzyme decarboxylase to break down ferullic acid in wort. It sounds like it's likely that certain wild yeasts are more able to produce this enzyme than WLP002 is, although I'm going to look at that too.

If it is this, then I have also read that 4VG breaks down over time and the clove taste will eventually dissipate, given time. I'll test this out.

Robsan, you mentioned Campden tablets. I don't keep a tick sheet when I brew, so I can't be 100% sure that I added a crushed campden tablet to ALL of my brewing liquor. I can only say that I "always" do...It's perfectly possible that I may have forgotten to add it to my sparge or mash liqour, or both. Or maybe when I crushed the tablet and tried to divide it in 2, I lost a load and didn't achieve proper chlorine conversion.

For next time, I think I'll renew all my hoses and maybe purchase a new fermenting bucket to be safe. I've brewed an APA since this beer, and it doesn't have this off flavour, so that makes me think it's something specific to that one brew.

Had a bit of a taste, and the beer still tastes great. The pint I've poured at cellar temp (12 degrees or so) isn't cloudy but definitely still has a slight clove taste. It does feel more spritzy though, and maybe a little lighter in body than I remember. No gushing though...I think I need to do a gravity test on it.

EDIT: Carried out a gravity test and it's still at 1.010. So, no wild yeast? :hmm: :wha:

I don't use chlorine based cleaners, so that just leaves the campden tablet issue or that the temperature dropped to 15C overnight early in the fermentation (though I don't know that it would produce 4VG because of this).