Specialty grains contribution to OG

PierreLo

Hi,
I am looking forward to make an imperial stout and have been playing with BrewFather to plan this recipe.
For the curious, the recipe ask for : 1.5 lbs of chocolate malt, 1.5 lbs of roasted barley, 1 lb of carafe special III, 0.5 lb of extra dark crystal
The specialty grains are added to the mash during the last 15 minutes mash out/vorlauf (@ 168 F).
Since the grains are not technically mash, I have used the steep option in BrewFather and realized that when steeped, grains dont contribute anything to OG (or FG) … and my brain had bug at that time.
From my understanding, OG is simply a measure of the amount of sugar extracted from the grains.
As long as I put grains in water, there should be sugar extraction, whether mash or steep.
The only difference between mash and steep in the enzymatic action that could transformed that extracted sugar into fermentable sugar.
I could understand that water temperature, time, ph or waterToGrist ratio could influence sugar extraction … but not mash vs steep.
Can someone help me understand that?
I would like to get my number right and unfortunately, Brewfather doesn’t help there.
Thanks

BrewnWKopperKat

Earlier this year, I did a couple of batches were I cold steeped the crystal / roasted malts (for up to 45 minutes) while making the main wort. For the steeped grains, SG (refractometer) and color remained consistent after about 30 minutes.
Steeping crystal / roasted malts will yield some fermentable sugar. Mashing crystal appears to yield more sugar (see Testing fermentability of crystal malt - link).

hotbeer

Remember the malts have starches that get converted to sugar by processes that are temperature and time dependent along with other things. When we steep, we are only going mostly for color and flavors. So that might be some of what you are seeing in the results with BrewFather.
Does steeping make a difference over mashing? Yes, there'll be a difference. However which results in something you prefer is pretty much individual preference.

IslandLizard

The mash converts starches into sugars by means of enzymatic activity. Steeping doesn't, there's no enzymatic activity, it only dissolves sugars and color and flavor contributors from the malts/grains.
Since the malts and grains are submerged in hot water, the mash will also dissolve sugars and color and flavor compounds, same as steeping would.

PierreLo

Am I right to think that starches will also increase OG because it’s a sugar? If I am right, steeping should also increase OG as long as starches are extracted and dissolved.
Mashing vs steeping should impact my FG because starches are converted to fermentable sugar through enzymatic activity in mash. But I don’t understand why steeping doesn’t impact OG.
Is it right that steeping doesn’t extract any starch at all? That is what BrewFather seems to imply.

Kickass

This might be the piece that’s missing:
Steeping is generally done with grains that have very little or no diastatic power, ie no enzymes to convert starch to sugars. When malted barley is kilned at higher temperatures or for longer periods (darker grains) it destroys the enzymes needed to convert starches. So, if you steep with only darker grains, you will mostly pull sugar that has been created while kilning.
Mashing, by contrast, typically involves “steeping” with grains that have high diastatic power, ie base malt. If you were to add some base malt to your steeping grains, you’d likely end up with more sugar. OR, if you add dark grains at the end of your mash, you’re likely to get more sugar.
I’d say the process you have outlined is mashing your dark grains not steeping them.
One more thing, the darker the grain the less potential sugar it has, regardless of whether it’s mashed or not.

BrewnWKopperKat

In the physical world, steeping malts will impact OG. This should be reflected in accurate (and properly configured) models for estimating recipes.
If you post a complete recipe (including water volumes) that would be helpful.

PCABrewing

Especially if you are steeping in the temp range of mash...

PierreLo

Here is the full recipe if you want :
IMPERIAL STOUT
(5 gallons/19 L, all-grain)
0G = 1.097 FG = 1.027
BU = 70 SRM = 100
ABV = 9.5%
INGREDIENTS
12 Ibs. (5.4 kg) U.K. pale ale malt
3 [bs. (1.4 kg) Munich Il malt (9
11b. (454 g) flaked oats
1.5 lbs. (680 g) U.K. roasted barley
(-550 °L)
1.5 lbs. (680 g) U.K. chocolate malt
(~440
•L)
1 Ib. (454 g) Carafa® III special malt
(~525 °L)
0.5 1b. (227 g) English extra dark
crystal malt(~180 °L)
12 AAU U.K. Chinook hops (60 min.)
(1 oz./28 g at 12% alpha acids)
1 oz. (28 g) Centennial hops (15 min.)
1 oz. (28 g) U.K. Golding hops (10 min
1 oz. (28 g) Chinook hops (dry hop)
1 oz. (28 g) Fuggle hops (dry hop)
Wyeast 1318 (London Ale Ill),
Imperial A38 (Juice), or LalBrew
Verdant IPA yeast
¾ cup corn sugar (if priming)
STEP BY STEP
This recipe uses reverse osmosis (RO
water. Adjust all brewing water to a I
of 5.5 using phosphoric acid. Add 1 t:
of calcium chloride to the mash.
This recipe uses an infusion mast
Use enough water to have a moder-
ately thick mash (1.5 gts./Ib. or 3.1 L
kg). Mash in the pale and Munich ma
and the oats at 152 °F (66 °C) and hi
for 60 minutes. Add the three dark
grains and crystal malt, stir, begin re
circulating, raise the mash temperat
to 169 °F (76 °C), and recirculate for
15 minutes.
Sparge slowly and collect 6.5 ga
lons (24.5 L) of wort in the brew kettle
Boil the wort for 90 minutes, adding
hops at the times indicated in the in-
gredients list.
Chill the wort to 64 °F (18 °C),
oxygenate then pitch the liquid yeast
or sprinkle two packets of dried yeast.
Ferment until complete, allowing the
temperature to rise as high as 70 °F
(21
•C). Dry hop for three days at
room temperature.
Rack the beer, prime and bottle
condition, or keg and force carbonate.

PierreLo

Since the dark grains are added to the mash during mash out at 168 F, there cannot be any enzymatic activity. So in my mind, it’s similar to steeping the grains.
The recipe is from BYO.
If you do the math, you will realized that they have considered OG from the speciality grains even though they are only added from 15 minutes during the mash out.

jerrylotto

I didn't see where you mentioned if the grains were all crushed, but why don't you mash everything together? If it's no problem for you to hold 153 f, just do it in fact I usually step mash with holds for acid rest, protein rest, and different beta and alpha rest steps. Even if the mouth is highly modified and it does nothing it doesn't hurt.

BrewnWKopperKat

FWIW, the full recipe from BrewFather would be necessary for further troubleshooting. (and, BTW, the BYO recipe is truncated on the right side).

As I mentioned earlier (from a different perspective) in #7, this could be either a configuration problem or a software problem. It could also be a problem with the original recipe. Consider trying a different recipe building app to see what it estimates.

Kickass

Thank you for pointing out (again) that youre adding the roasted malt during the mash out, I missed that. I wouldn’t be surprised if you get a little conversion still at 168, depending on how long it’s been there and when you add the grain. If you add the grain then bring up to 168, or do it simultaneously there will likely be some enzymatic activity.
Now for the practical part, it’s probably negligible and impossible to know.
FWIW, I always mash my dark grains but I know others “cap” their mash or add them at the end. For me it’s a simplicity thing.

Bobby_M

If you're only putting them in at mashout, leave it at steep. You won't get any appreciable SG gains. If you add them at mash temps, edit the grain to be mashed and set a short time like 1 minute.

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PierreLo

Thanks guys.
I have also read that when steep, grains don’t add much to gravity.
I am pretty sure that BYO assumed that all their grains were mash when calculating their OG … Which seems weird to me since the dark grains were only added for 15 minutes during the mash out.
I think that I have more luck hitting my numbers assuming no SG from dark grains.

BrewnWKopperKat

True - steeped grains don't add much, but the amount added can be estimated and measured.
To confirm this, one would need to know the mash efficiency, PPG for each of the malts, and the SG contribution for each malt.
In the BYO recipe, the water adjustments process has a number of distinctive steps (RO water, adjust water to pH 5.5 using phosphoric acid, 1 tbl CaCL, mash capping) to suggest that this is a recipe by Gordon Strong (he writes articles for BYO). It's plausible that mash capping wasn't modeled well by whatever software BYO used when the article was written.
Again, it will be noted that recipe software provides estimates, not reality.
Recipe software that shows assumptions (PPG, mash efficiency, ...) and intermediate results (SG contribution for each malt, ...) certainly makes troubleshooting discussions easier.

Bobby_M

This whole topic of late roasted malt additions is weird. The idea behind it is that it's less harsh but there are a couple flaws in the logic.
Dark roasted malts by their nature are roasty, bitter, coffee like, dark chocolate, etc. We use them in recipes specifically for these characteristics. If you use x amount in a mash for the full mash and find the beer harsh, you've used too much. Back off on the amount. Of course if you leave them in the mash for 1/10th of the time, the flavor extraction is going to be less but as noted you won't get any gravity from them. They already have much less remaining extract potential as it is.
You lose all the acidifying benefits of the dark grains to bring the mash pH down. For the majority of tap waters out there, and certainly most well water, the acidification from the malt is much better than having to add lactic or phosphoric acids.

BrewnWKopperKat

Earlier this year, I did a cold steep of 1 lb Special B (double crushed) in 1 gal water.
After 10 min, the SG was 7 (refractometer). After 30 min, the SG was 11 (refractometer & hydrometer)
OP had roughly 4 lb of crystal/roasted malts in a 5 gal batch - so maybe an SG contribution of 4 - 8 GPs

IslandLizard

Dextrins add to gravity, right? How about larger molecules and starches?

BrewnWKopperKat

Yes - so in general, steeping of malts (crystal, roasted, base malts [1) will contribute to OG. How much depends on the batch size and the amount of malt used.
As for the fermentability, a number of years ago, I did steep / pasteurize some Crystal 60 and throw some US-05 at it. In the end, FG was lower then OG. I would anticipate that roasted malts would behave similarly. It might be interesting to ferment crystal / roasted malts side-by-side 'experiment' using Nottingham and Windsor [2].

[1] cold extraction (steeping base malts overnight in cold water) is a reasonably well known technique for making a low ABV wort - the point being that base malts appear to contain some fermentable sugar without needing to mash.
[2] Windsor doesn't ferment complex sugars (maltotriose, ...).

kevin58

I liked the original reply above but I'm unable to "like" it more than once. So - LIKE LIKE LIKE LIKELIKE LIKE LIKE LIKELIKE LIKE LIKE LIKE etc. Denny Conn says, paraphrasing... 'Use as many malts as you want as long as you can justify each one'. You can add to that... Use the right amount.