Mashing Dark Grains

[lou]

Hi ya all

Ok so i punched a stout recipie into promash - its a small batch with plenty of black patent and choc but promash rekons that the dark grains are adding sugars or at least upping the OG. i though these malts had no sugar and only contribute flavour and colour, the starch is burnt away as i understood it - whats this all about :blink:

oh and also do i just chuck all the dark grains in with the rest at the beggining of the mash or a bit later

lou

 

[Sean]

Hi ya all

Ok so i punched a stout recipie into promash - its a small batch with plenty of black patent and choc but promash rekons that the dark grains are adding sugars or at least upping the OG. i though these malts had no sugar and only contribute flavour and colour, the starch is burnt away as i understood it - whats this all about :blink:

oh and also do i just chuck all the dark grains in with the rest at the beggining of the mash or a bit later

lou

[post="53100"][/post]​

Dark grains do contribute sugars as well as the flavours and colours (albeit in reduced amounts).

All my grains go through the mill together, so the dark grains end up very evenly distributed through the mash.

 

[joecast]

i dont think promash will differentiate types of grain when calculating gravity. basically regular ale malt will give the same contribution of sugars as crystal or chocolate malt. so remember to take that into account. they will contribute to the original gravity, but they will be much less fermentable. hope that helps.
joe

 

[Gulf Brewery]

i dont think promash will differentiate types of grain when calculating gravity. basically regular ale malt will give the same contribution of sugars as crystal or chocolate malt.

[post="53108"][/post]​

Hi joecast

Promash (and I assume those other copycat programs) do take into account the amount of sugars that can be extracted from the grains.

Cheers
Pedro

 

[Kai]

I think what joe was saying is that the contents of the dark grains are added to the OG, regardless of their fermentability and ignoring that promash probably does account for their fermentability as probably reflected in the predicted FG

 

[jayse]

No promash doesn't take into account fermentabilty of the grain, as far as that is concerned you would get the same attenuation for 5kg of ale malt as you would for 5 kg of cararoma.

it only calculates the expected yield and colour for each grain.

Jayse

 

[Dunkel_Boy]

With when to add dark grains, some people get a smoother beer by adding them later in the mash, say the last 15 minutes. But, with our soft, highly carbonated water in Brisbane, it doesn't really make a difference. The late dark grain addition I think is mostly meant for the high-sulphate water brewers.

 

[sosman]

Ok so i punched a stout recipie into promash - its a small batch with plenty of black patent and choc but promash rekons that the dark grains are adding sugars or at least upping the OG. i though these malts had no sugar and only contribute flavour and colour, the starch is burnt away as i understood it - whats this all about :blink:

[post="53100"][/post]​

No need to guess, check the malt specs, eg joe white:
http://www.maltcraft.com/joewhitespecs2.html

 

[Sean]

With when to add dark grains, some people get a smoother beer by adding them later in the mash, say the last 15 minutes. But, with our soft, highly carbonated water in Brisbane, it doesn't really make a difference. The late dark grain addition I think is mostly meant for the high-sulphate water brewers.

[post="53133"][/post]​

The dark grains will affect the mash PH, so I suppose it would make a difference. I just prefer to keep things simple - in the grand tradition of English brewing.

 

[lou]

thanks people

the darker grains do apparently add sugars as the specs seem to suggest but this is totally inconsistent with saying that all the starches get burnt away in the kilning process. No starches, no conversion ,no sugars simple as that.

It does beg the question as to what happens to the starches if not mashed which you can do ( i have done in kit brews). do you get unconverted starch in the final beer? You might not be able to see it in a dark beer but would it have a particualr flavour effect?

just something to think about

lou

 

[Jovial_Monk]

Dark malts (the roasted, not the crystal variety) have about 10% fermentability, but they contribute to original gravity at a rate about 90% of pale malt.

And I prefer to cold steep them if adding in significant amounts.

Jovial Monk

 

[joecast]

thanks people

No starches, no conversion ,no sugars simple as that.

lou

[post="53199"][/post]​

true, but some base malts have higher "diastatic power". this allows them to convert more starches to sugar making them better to use with adjuncts. more technical explaination here:
http://www.howtobrew.com/section3/chapter14-5.html
joe

 

[Ross]

Dark malts (the roasted, not the crystal variety) have about 10% fermentability, but they contribute to original gravity at a rate about 90% of pale malt.

And I prefer to cold steep them if adding in significant amounts.

Jovial Monk

[post="53201"][/post]​

I'm with you on the cold steeping, JM, especially as I don't have a ph meter yet...

 

[user 384]

Dark malts (the roasted, not the crystal variety) have about 10% fermentability, but they contribute to original gravity at a rate about 90% of pale malt.

This explanation has got me puzzled. Crystal malts are the only grains where the starches have already been converted to sugar, so their fermentability is basically predetermined. The fermentability of wort produced by all other malts, including roasted malts, is mainly dependent on the mash temp (yes I know mash thickness and a few other factors impact on the fermentability but this impact is small compared to mash temp). Just because the starch has been roasted doesn't mean the process of converting it to sugar will change, therefore the same principles of low mash temp = high fermentability and vice versa still apply. However after the malting and kilning process, it may have overall less starch left to be converted to sugar, hence the lower contribution to final gravity than other malts.

If anyone has an alternative explantion of how the starches in roasted malts get turned into sugar I would love to hear it.

It does beg the question as to what happens to the starches if not mashed which you can do ( i have done in kit brews). do you get unconverted starch in the final beer?

Yep Lou, you're right. Although a lot of people say you can steep roasted malts for extract brews, you need to be aware that it will add colour, some flavour and also unconverted starch. Only crystal malts can be truly steeped.

Cheers
MAH

 

[Jovial_Monk]

We could postulate some mashing occurring in the grain as the roasting temperature passes through the 50-80C range where amylase activity can occur. It must do because dark grains are slightly fermentable.

The amount of starch left must be tiny. So when steeping or mashing 50-800g roast malts the starch contributed by the dark grain is correspondingly tiny, and any consequent starch haze is invisible in the dark beer. When adding less than 50g roast to slightly darken a beer the amount of starch contributed is microscopic and no starch haze is detectable.

Personally, an amount of 100g or less of roasted malt in a 6Kg+ mash I would add to the mash. When doing a stout with lots of chocolate malt and roast barley I cold steep the roast grains.

In either case, the starch is negligible and need not be considered.

JM

 

[Gulf Brewery]

We could postulate some mashing occurring in the grain as the roasting temperature passes through the 50-80C range where amylase activity can occur. It must do because dark grains are slightly fermentable.

The amount of starch left must be tiny.

[post="53244"][/post]​

JM

If you think that the malt is mashed when it is roasted, then the starches should be converted to sugars and the roasted grains would contribute the same amount of sugars and fermentables as a pale malt. I don't think the roasting of grains could mash the malt, especially as roasting is a dry process (the making of crystal is different in that it is stewed).

Cheers
Pedro

 

[Wortgames]

I think there are a couple of concepts getting mixed up here. Kilning denatures a lot of the enzymes (therefore reducing the diastatic power) of the grain, but I'm not sure I've ever heard of it having a significant effect on the amount of fermentable sugars it yields. Yes some of the starches will be converted during the kilning process, but the remainder will be converted in the mash as normal.

If you were trying to brew exclusively with dark malt, the reduced diastatic power would be a problem, but in a normal mash it isn't an issue as any pale malt has more than enough enzymes to convert the starches in the darker malts.

 

[Jovial_Monk]

So how does the fermentable component get in the dark grains, Pedro? Dried grain still has, ummm, 2% moisture?

JM

 

[Gulf Brewery]

So how does the fermentable component get in the dark grains, Pedro? Dried grain still has, ummm, 2% moisture?

JM

[post="53258"][/post]​

JM

I'm not sure I understand what you are saying here - you said about the mashing and fermentables in the grain. As I understand it, the starches are converted to fermentable sugars by enzymes no differently to a pale malt (though at a lower level of available sugars) during the mashing process.

Pedro