Alpha Acid % and Hop Flavour

[dlowe1992]

Has anyone found any correlation between lower AA% hops and hop flavour/aroma.

I ask as I was looking at a recipe the other night using willamette and styrian goldings at 4% AA ish each.
Checked CML and their stocks for both are around the 2% mark.

I know AA contributes bitterness when boiled. Obviously if used for bittering I’d double up, but these would be hopstand additions in this case. Is there any reason to believe the hops in general (oils etc for hop flavour) would be less ‘powerful’ and as such the dose need increasing?

 

[Stu's Brews]

Has anyone found any correlation between lower AA% hops and hop flavour/aroma.

I ask as I was looking at a recipe the other night using willamette and styrian goldings at 4% AA ish each.
Checked CML and their stocks for both are around the 2% mark.

I know AA contributes bitterness when boiled. Obviously if used for bittering I’d double up, but these would be hopstand additions in this case. Is there any reason to believe the hops in general (oils etc for hop flavour) would be less ‘powerful’ and as such the dose need increasing?

For flavour/aroma you need to consider the oil content of the hops rather than the alpha acid content.

As far as I know, there is no direct correlation between alpha acids and oil content.

Unfortunately it is rare at a homebrew level that you can find out the oil content of the hops you are using, so you are largely relying on typical averages for each hop variety.

This article is quite interesting and somewhat relevant to this discussion: What is Hop Oil? |

 

[Alan_Reginato]

If there's a huge difference in the AA %, probably there's some difference in the expected hop characteristics.

I wrote a post about Saaz, but could be the same case of yours.

I bought these hop package recently

View attachment 93246

The 1st (left to right) is 2021, AA 4,3%. The 2nd, 2022, AA 2,6%. And 3rd, the same, but from a different brand.

And, WTF!?! I could tell them apart. Visual, 1st was dark green, 2nd light green and 3rd looks drier, brownish comparing to the others.

About flavour, 1st had a more herbal, intense hoppy. The 2 others had a more floral, citric accent. With the last package being less prominent.

It's the first time a bought hops from different years or brand at same time, so I could compare them, side by side.

It's normal such a big difference? How the hell brewers could achieve repeatability in this way?

 

[Twostage]

I'm reading a book a the moment 'The New IPA - a scientific guide to hop aroma and flavour' (its actually flavor but I've Anglicised it ). Crikey, its complicated. I'd use them as indicated in the recipe and see what it's like.

 

[Northern_Brewer]

It's complicated - low alpha can be a pointer of low hop oils, but not always, the relationship is really messy. Just take the UK 2023 harvest where some alphas are on the lowish side, some are OK, but the flavour in most cases really isn't great at all, it was nuked by the bad weather in August.

It also has different relationship depending on the area the hops are grown in, hops from Yakima will be much more consistent than hops from the UK which can show massive vintage effects.

 

[dlowe1992]

Thanks for the replies, all interesting stuff. As they are low alpha hops I will probably increase a touch should I go ahead and brew, as I would prefer it on the hoppier side and there'll be marginal bitterness effect from increasing a hopstand at 2.1%

@Alan_Reginato - how did you find the Saaz in use? Sounds from the description almost like two different hop profiles between the first and second packs?

On a home brew scale, some variation perhaps not so important. At the end of the day, if you're still making a good beer, you're still making a good beer. Shows some of the skill in maintaining consistency on a commercial scale I suppose..

 

[hoppyscotty]

And they vary from harvest to harvest. The pro breweries will choose hops based upon how well that particular hop has done that season and adjust recipes accordingly, so a particular headlining IPA form a brewery might be a different recipe from one year to the next as they change hops to get the ones that are particularly good that season.