Reducing Darkening In Extract Brews

[hopmonkey]

if i am following an extract brew and i need it to be pale, like a pilsner how would i go about this?
all instructions point to adding lme or dme at the start of boil along with the first hops. This of course causes the wort to darken, even with a full volume boil.
Is it ok to just boil the hops in the water for 45mins then add extract at 45 mins to so it gets a full 15 min boil to sterilise?
or does the wort extract different compounds from the hops than water alone?

 

[Stuster]

There will be differences with just boiling water. You can add roughly 20% of your malt extract to the boil at the start, boil with the hops, then add the rest of the extract at 15 minutes (even later should be ok. The malt extract should be sanitised by a few minutes of boiling, but 15 minutes is playing it safe.) You still get the hop utilisation but less darkening.

 

[Voosher]

The difference in hop extraction rates between a 1040 SG solution and water is somewhere in the region of 40% higher in water so you need to make sure you're getting those numbers adjusted as well. And not that I know for sure but it wouldn't surprise me if boiling in water only has a slightly different effect in terms of extraction of flavours etc.
As Stuster said, boiling a small amount of your extract and adding the rest towards the end of the boil is a better plan. Personally I've never noticed significant darkening of an extract over a 60m boil.

 

[Stuster]

From what I've read Voosher, boiling hops in just water does make a difference. This is from BYO.

When hops are added to wort and boiled the pH is around 5.2 and there is protein present to precipitate much of the polyphenols extracted from the hop leaf. Boiling time is important and most beers that have hop aroma use late additions. During the boil, hop acids undergo numerous chemical changes and the resultant mix has a profound influence on beer bitterness and the quality of bitterness. When the pH of wort boiling is increased by adding alkaline buffers, hop utilization increases but bitterness is reportedly unpleasant. If you boiled hops in water as opposed to wort, the pH would be higher and the flavor would lack.

I've never tried boiling in water myself though. Anybody tried it?

If you can do a full boil though, just add all the extract and as Voosher says there shouldn't be too much darkening in that case. If not, use proportionately less extract.

 

[Voosher]

From what I've read Voosher, boiling hops in just water does make a difference. This is from BYO.

When hops are added to wort and boiled the pH is around 5.2 and there is protein present to precipitate much of the polyphenols extracted from the hop leaf. Boiling time is important and most beers that have hop aroma use late additions. During the boil, hop acids undergo numerous chemical changes and the resultant mix has a profound influence on beer bitterness and the quality of bitterness. When the pH of wort boiling is increased by adding alkaline buffers, hop utilization increases but bitterness is reportedly unpleasant. If you boiled hops in water as opposed to wort, the pH would be higher and the flavor would lack.

I've never tried boiling in water myself though. Anybody tried it?

If you can do a full boil though, just add all the extract and as Voosher says there shouldn't be too much darkening in that case. If not, use proportionately less extract.

I did my flavour boil in water only in my very early days of enhancing kits and before I could probably notice too many negatives overpowering the kit twang. I doubt I'd bother now.

Interesting read. Thanks Stu.

 

[matti]

how bout adjusting the ph of the water prior to boil?
interesting article.
Though I believe still that one should avoid adding the the lme an dme until last ten to twenty minutes.
Espcially if it has hops in it.

 

[Andyd]

They Guys on BasicBrewing Radio/Video had a shot at this recently. John Palmer was quoted as having concerns about "grassy flavours" resulting from boiling the hops in water alone. The guys did the experiment both ways and couldn't detect such flavours...

It's worth finding the podcast...

AndyD

 

[Stuster]

That's interesting, Andy. I had a look through their radio page but couldn't see which episode that experiment might be on. Do you know which episode it was?

 

[Coodgee]

I think the most important thing is to buy a fresh can of goo. they darken over time in the can.

 

[Andyd]

Try April 13 or May 11...

AndyD

 

[pxpx04]

That episode from basic brewing radio is from the 15th December 2005.

They did 2 extract brews both with the same amount of hops and the same length boil (60 mins). The difference was that in the first case, the malt extract was added at the start of the boil with the hops, and in the second case, the hops were added in just water and malt extract was added 15 mins before the end of the boil.

In short, when they tasted the brews, they found that the brew where the malt was added for 60 mins was noticeably darker. Taste wise, both drinkers preffered the second case, where the hops were added at the beginning of the boil and the malt was added 15 mins from the end. They commented that it had more bitterness, and was a more well rounded bitterness.

As Andyd mentioned, John Palmer was concerned that boiling the hops in water only may result in a 'grassy' taste. He suggested that if you did not want to darken the beer, you should add a quarter of an eighth of the malt at the beginning with the bittering hops, and add the rest 15 mins before the end of the boil.

I can't offer any personal experience on the matter, but if anyone is interested, the video is quite interesting and explains in much more detail.

pxpx

 

[Stuster]

Thanks for the info, andyd and pxpx04.

 

[Andyd]

Good one pxpx - it was too late for me to go trawling properly through the audio.

AndyD