Roast Barley and FG

[bracconiere]

So I just kegged up a stout, or close too it.

My question is, even with gluco it finished at 1.007, i used 2lb's roast barley in a 10 gal batch.

Would the fact roast barley is unmalted raise the FG that much, even with gluco? Beeing that i've making my own malt for a while, and now going back to buying it, haven't really used Roast Barley with gluco..

Anyone else? And another question would be if you think it is the roast barley, take a guess if it would have more calories.?

 

[Hayden123982]

when did you add your gluco?

 

[bracconiere]

right before i started the boil


(yes i know how to use gluco, i added it the ferment with the yeast pitch)

 

[bracconiere]

i should mention the beer OG was ~1.071, so i'm pretty sure 1.007 would be low, just not as low as i'm used to (i.e. 1.000)

 

[Vale71]

Well, roasted barley is basically just barley that is burnt in a controlled fashion. The fact that it is unmalted is rather irrelevant considering that starch that has been burnt cannot be converted any more during the mash as it is now basically just ash. Long story short, the extract you get either from roast barley or from roast malt is basically unfermentable, so yes, it is normal that if you use a large portion of it you'll get lower attenuation even if you add enzymes to the mash as even those enzymes cannot convert ash.

 

[bracconiere]

Well, roasted barley is basically just barley that is burnt in a controlled fashion. The fact that it is unmalted is rather irrelevant considering that starch that has been burnt cannot be converted any more during the mash as it is now basically just ash. Long story short, the extract you get either from roast barley or from roast malt is basically unfermentable, so yes, it is normal that if you use a large portion of it you'll get lower attenuation even if you add enzymes to the mash as even those enzymes cannot convert ash.

thanks for the response!

i did a batch with 2lb's black patent, and it went to 1.000 though. why i was curious...the difference i was getting at is black patent is mashed in the kernel before roasting though, so it would be caramelized sugar, not ash like roast barley....

i just wasn't sure if 'ash' would dissolve in water to give gravity points...

 

[Hayden123982]

I wouldn't have thought that it would have been the "ash," but maybe you could do a quick cold steep and check to see if that gets gravity points?

Also, how's the beer taste? Ive been curious on doing glucoamylase in a dark beer but was worried that no residual sweetness would create something too roasty

 

[bracconiere]

quick cold steep and check to see if that gets gravity points?

good idea. the roast barley isn't that good, the black patent that finished at 1.000 was delirious(damn spell correct, you know what i mean. but the same goes!)....(had to salvage this roast batch by adding strong coffee to the keg)

edit: i think it'd have to be a hot steep though....

 

[day_trippr]

[...]starch that has been burnt cannot be converted any more during the mash as it is now basically just ash.[...]

This carbohydrate "ash" is soluble and registers on a hydrometer?

Cheers!

 

[bracconiere]

This carbohydrate "ash" is soluble and registers on a hydrometer?

Cheers!

thank you for more eliquiently(sp?) stating my original question!

 

[Vale71]

i just wasn't sure if 'ash' would dissolve in water to give gravity points...

Indeed it does, although with reduced efficiency. If you look at the grains database of brewing software such as Beersmith you'll see that roasted barley and malt have a significantly lower potential than base malts. Roasted malt does have a slight fermentability as opposed to roast barley. Weyermann's Sinamar is beer made with a 100% Carafa Special grist, unhopped and then fermented as this is a legal requirement to be able to label it as beer instead of an additive which in Europe would then get an EXXX number to which beer consumers react negatively. Rumour has it it doesn't even come close to 1% ABV which then completely evaporates in the subsequent vacuum evaporation process, making the final product condensed alcohol-free beer from a legal standpoint.

 

[bracconiere]

Roasted malt does have a slight fermentability as opposed to roast barley

Thanks!