Bitterness In An Unhopped Beer

[jjeffrey]

Not too long ago, some collegues and I prepared a large wort and split it into 12 batches, all of which were hopped in a different manner. The idea was to be able to easily discern the effects of the various hopping regimes by tasting the beers side by side.

This we did, and I'm in the process of writing up a report on the whole experience (watch this space).

What has puzzled me somewhat was a bitterness that we had in the control sample, which was a completely unhopped beer.

The bill was straight Joe White pilsener malt, mashed with a 15 minute protein rest at 55C, then an hour at 63C and a mash-out at 70C. It was fermented with Wyeast Californian lager (2112). Fermentation temperature control was non-existant, but the babies spent about a week at cellar temps of 12-14C (barely any action), followed by 5 days at cellar temps of 16-23C.

I can't explain the bitterness that we tasted in the control sample, which was picked up by all 6 members on the evaluation panel. I would have expected it to taste pretty neutral. Some (I was one of them) described it as a harsh bitterness. Personally, I would have sworn it was bittered with PoR had I not been there when we made it.

Has anyone any idea how we may have got bitterness without hops?

jj.

 

[alexbrand]

Interesting experiment!

Bitterness for example comes also from the grain husks. They have tannin.

Alex

 

[Fourstar]

tannins? Husk Astringency?

 

[jjeffrey]

Tannins? yeah- that was my first thought, but we purposely left lots of sugar in the lauter tun to avoid over extraction- only about 65% efficiency. We were also really careful with pH, which didn't rise above 6 during the lauter.

I suppose it could be that tannin bitterness, although small, comes to the fore when there is absolutely nothing else to hide behind.

 

[Stuster]

Is there any chance that labelling of the different batches was...um...less than optimal.

Well, otherwise, could it be flavours from the high fermentation temps that you are picking up? Fusels certainly taste rough, and could be perceived as bitter I suppose, especially in combination with some phenols.

The only other thing that comes to mind is contamination. Any chance that could have been what you were tasting? Did you take the FG on the batches? Was the body thin?

 

[dr K]

Hops are an important preservative in beer, spoilage seems to my mind without actually evaluating the beer fairly high on the list of possibilities (which is a very short list !!)

K

 

[jjeffrey]

Is there any chance that labelling of the different batches was...um...less than optimal.

Anything's possible, but I really doubt it. All of the other batches tasted of finishing hops.

Well, otherwise, could it be flavours from the high fermentation temps that you are picking up? Fusels certainly taste rough, and could be perceived as bitter I suppose, especially in combination with some phenols.

Could be. 2nd half of the fermentation rocketed on in some parts, and there were some pretty significant temperature swings (6C or so). Also, "fusel" and "alcohol" were descriptors used by most of the evaluators in descriptions of aroma.

The only other thing that comes to mind is contamination. Any chance that could have been what you were tasting? Did you take the FG on the batches? Was the body thin?

No- ended at 1.011, and stayed there for a couple of months. No other off-flavours that I would attribute to other beasties. Sanitisation was really good.

I like the fusel theory. It fits. If so, characters described for the other batches may be biased. I've not tasted many fuselly beers, can anybody give me typical descriptions of fusel characteristics which I may use to filter my data?

 

[Thirsty Boy]

I have a barleywine that i can give you to try - thats a lovely example of fusels. Or at least thats what I taste and several comp judges tasted (just before they spat it out I imagine)

Remind me and we will go for a beer and I will bring you a bottle.

I remember that beer vaguely .. I lean towards it being bitterness from the higher alcohols. I don't think infection, I don't think contamination (although I am not sure) and the other beers (form the same wort) weren't noticeably astringent IIRC although I am not great at picking out astringency, so I might be wrong there.

I suppose it could be malt derived (fungal infection??) or astrngency - and it was there in all the beers - but we didn't pick it up in the others because they were hopped and it wasn't strong enough to raise its head above the hop bitterness in a noteworthy way???

 

[Barry]

Water? pH?

 

[jjeffrey]

Water? pH?

Thanks Barry. Don't think so. Very clean Melbourne water from the Silvan Dam, conditioned to to give this:

Calcium(Ca): 96.5 ppm
Magnesium(Mg): 10.5 ppm
Sodium(Na): 4.7 ppm
Sulfate(SO4): 131.3 ppm
Chloride (Cl): 102.2 ppm
Bicarbonate(HCO3): 13.6 ppm

Mash pH was 5.3 all the way.

I have a barleywine that i can give you to try - thats a lovely example of fusels. Or at least thats what I taste and several comp judges tasted (just before they spat it out I imagine)

Remind me and we will go for a beer and I will bring you a bottle.

Ta. I'll be calling a meeting soon (next 2 or 3 weeks), so that would be opportune. I'll bring the tasting notes. I also have a number of lagers I want you to put your hersbruker bias tongue against: we'll roll it together.

I remember that beer vaguely .. I lean towards it being bitterness from the higher alcohols. I don't think infection, I don't think contamination (although I am not sure) and the other beers (form the same wort) weren't noticeably astringent IIRC although I am not great at picking out astringency, so I might be wrong there.

Your aroma description was "fusel", and flavour description was "sweet, with some bitterness". I'm becoming convinced that higher alcohol was the cause. Very interesting to get flavours like that from higher alcohols- it can really throw the character of the beer beyond "solventy", it seems.