How dark can wort become from boiling?

[yeknom366]

I made an Irish Red ale last year, and the expected SRM was 20. However, it looked black in a glass, but bright ruby red when a light was behind it. Tasted great, so I thought it was no big deal.

This year, I made another Irish Red ale with a few tweaks that happened to lighten it, and the SRM should have been 14. It's barely lighter, but still almost black with the same ruby redness with light behind it. Again, this is in the glass, not in the fermenter. Photo in glass - http://i.imgur.com/KctPW9v.jpg

I know wort will definitely darken during boiling, but I assumed this was factored into most calculators. My SRM values were from BrewersFriend.com, and the recipes are below. This is more just a curiosity question than worrying if it's bad or ruined.

Last year (5 gallon):

8 lb Vienna
1.5 b Dark Munich
0.5 lb Crystal 77°
0.25 lb Roasted Barley

This year (4.5 gallon):

8.5 lb Vienna
1 lb Dark Munich
0.375 lb Wheat
0.25 lb Roasted Barley


Again, both tasted great. I am just curious as how dark wort can become via boiling or another reason as to why they would turn out looking more like a dark brown ale or porter in color.

 

[alane1]

I think the culprit might be the combo of Vienna and Munich, these malts tend to exaggerate color. Try pale two-row next time or cut the amount of roasted barley to 2oz. Cheers

 

[kh54s10]

What roasted barley are you using. I found listings from 300 srm to 695 srm. That could make a pretty big difference.

There may also be a big range of srm on the Dark Munich depending on maltster.

Beersmith gives about 20.4 on my profile at 4.5 gallons of your lighter batch. It looks dark red in the depiction.

Another thought. The two recipes may make the same srm based on 5 gallons on the first one and only 4.5 on the second.

I second trying some lighter malts.

 

[yeknom366]

I used the following malts and lovibond:

Briess Vienna - 3.5
Briess Roasted Barley - 300
Briess Dark Munich - 20
Weyerman White Wheat - 1.5
Crisp 77° - 77 (duh)

Also, the photo was attempting to get light behind it. Barring putting a bright light directly behind it, that's as light as it ever looks.

When I changed the second batch from 4.5 to 5 gallons, it only decreased the srm by ~1, so it's not just a simple concentration issue.

 

[JimRausch]

I think your problem is in the 1/4 lb of roast barley. My Irish Red has a similar base but only 1oz. roast barley for a SRM of 13.

 

[yeknom366]

If the problem is the 4 oz of roasted barley, why are multiple SRM calculators giving me an incorrect value?

 

[azazel1024]

Yeast? An Irish red I did with an SRM of 14 with Windsor yeast that ended up not fermenting out before I bottled due to stuck fermentation right at the tail end (and did NOT realize until after bottling as my attenuation was only a few percent low) has WILDLY different appearance depending on how much yeast is in suspension when pouring it.

If I manage a clean pour (hard to do when over carbed) it some some garnet colors to it and I'd say it is a in the 14 range, but if I manage to get some yeast mixed in on the pour, it looks darker and browner more in the 20 range.

Beyond that, general solids in suspension or chill haze could darken the appearance of the beer as well.

 

[yeknom366]

I used wyeast 1084, and whirlfloc. With light, it's very clear.

 

[ImNoExpert]

I'd cut the roasted barley in half next time and see how that does.

 

[yeknom366]

So nobody can answer the original question, and everyone posting is saying it's the roasted barley while dismissing all calculations of SRM?

 

[GuldTuborg]

Did you ever rebrew this?

What's your water like? If you're able, check your pH going into the kettle. The only other likely explanation I can think of is a high pH wort with a strong boil. That will cause considerable darkening of the wort every time.

 

[yeknom366]

Haven't brewed again yet. I've done it the last two years for St. Patrick's day, so probably late next fall.

 

[pablosbrewing]

So nobody can answer the original question, and everyone posting is saying it's the roasted barley while dismissing all calculations of SRM?

In all grain, wort darkening in the boil (edit: should be) negligible. Otherwise you wouldn't be able to get Pilseners, those boil for 90 minutes as a rule.

So wort darkening is essentially a partial boil concern - unless you have oxidation.

 

[yeknom366]

In all grain, wort darkening in the boil (edit: should be) negligible. Otherwise you wouldn't be able to get Pilseners, those boil for 90 minutes as a rule.

So wort darkening is essentially a partial boil concern - unless you have oxidation.

That's what I thought... maybe I just got false lovibond numbers on my grains. O well, it still tastes amazing.

 

[Yooper]

That's what I thought... maybe I just got false lovibond numbers on my grains. O well, it still tastes amazing.

Did you actually use the Briess' lighter colored roasted barley? If you did, it shouldn't be too dark but most roasted barley grains are more like 500 SRM.

 

[ajdelange]

So nobody can answer the original question, and everyone posting is saying it's the roasted barley while dismissing all calculations of SRM?

Dismissing calculation of SRM indeed the right thing to do. One cannot hope to be even approximately right. The question is the title "How dark can it become..?" has answer depends on how long you boil (or cook it otherwise). Take some DME, put it in a pot with some water and commence a boil. Keep checking. Eventually you will have a really dark syrup. Heat, amino acids and sugars react to produce coloring compounds.

When 'calculating' color of a beer one uses the Lovibond number published by the maltster. This is the color of a Congress wort made using practices that are quite different from what one does with the malt in the brewhouse. Furthermore, a Lovibond color of over 21 (or something like that) doesn't mean anything because 1) the Lovibond glasses don't go above 21 and 2) The Lovibond glasses don't have the colors of beer or wort. When doing 'bold extrapolation' as one does when considering grains of 40L etc. don't expect much in the way of accuracy.

Because home brewers tend to use direct heat or electric coils temperatures, and thus color development, in their worts tend to be higher than in commercial operations using the same materials but with more gentle heat.

As a final observation, beer is inherently red. The more coloring material is developed in a brew (the more heat) and the longer the path (wider the glass) through which the beer is brewed the redder it becomes. That is why you see a very pure red light when looking at a stout with a bright light shining through it.