BYO Recipe Efficiency 65% vs. Your Efficiency

[Piratwolf]

I'm not a chemist and I don't even play one on tv. However, it seems to me there's a logical flaw in ChillWill's protest. I think it doesn't matter whether roasted grain flavor & color diffuse at the same rate as sugar. I think that what matters is that roasted grain flavor & color diffuse at a rate that's constant whether there's 10 oz or 10 lbs in the recipe, and that's why they're calculated as a % of the grain bill.

"All your home brew are belong to us!"

 

[MalFet]

In my mind sugar relies on enymes whereas the flavour contribution is more about the roasted bits being dissolved in water and therefore it is unlikey they're at a the same rate.

I certainly see where you're coming from, but I think this line is the crux of the disagreement. With fully modified grain, it seems to me that you *are* pulling both sugar and color at roughly the same rate.

In a proper setup, everyone would agree that efficiency variations should be limited to sparge efficiency, not to conversion efficiency (i.e., if someone is getting conversion efficiency below 95%, it's because of a problem, whereas sparge efficiencies will routinely vary between 65-85% depending on configuration).

But, in either case, it seems that what comes out of your mash tun is proportional to what went in, and I think this notion is borne out empirically. Certainly different quantities of grain will impact pH (slightly), but all the brew calculators actually seem to account for this. But, what you are hypothesizing is that color molecules are pulled into wort at a higher rate than sugar molecules, and I don't think I've seen anything to suggest that's true.

 

[LandofOZ]

they said there would be no math invovled!!!!!!!!!!!!!!!!!!!!!!!!!!!!!

 

[BrewKnurd]

Yoops - I'm well aware how to scale, that isn't the issue and I don't know why you think that is. The point is, if you just blindly scale then you're basically saying flavour/colour extraction increases or decreases at the same rate as sugar extraction, this is what I have an issue with and I don't believe it to be true.

In your opinion; is the flavour of dark grains extracted at the same rate as sugar?

In my mind sugar relies on enymes whereas the flavour contribution is more about the roasted bits being dissolved in water and therefore it is unlikey they're at a the same rate.

But you have to keep in mind that they could happen at different rates and still end up at the same place at the end of a 45 minute mash. Lets say it takes 20 minutes to extract all the flavor and color compounds, but 40 minutes to convert the available starches to sugars.... with a 45 minute mash it wouldn't matter that they didn't happen at the same rate, they would end up at the same place. Anyways, those are just numbers I made up, but just believing that the rates are different does not necessarily mean that different efficiencies will result in significantly different impact of dark grains (or any grains, but we've mainly been talking about dark here).

If it was depended on mashing, how come if you steep dark grains with no base malt you get flavour and colour?

I don't think anyone ever claimed that extracting color and flavor from dark grains required mashing.

 

[Barnstormer]

Chillwil: You mentioned coffee. Do you also cook? Many ingredients go into one dish. Some, like salt and garlic come through much stronger than others. If I'm having company and have to double the recipe, it all gets doubled, not just the ones that taste stronger.

Same with the beer. Like cooper said, you scale by %. I understand that the dark grain may contribute color, flavor, ph more heavily. The base malt may contribute less pound for pound, but there is so much more of it that it keeps it in check. Keep the %'s the same and you should be fine.

 

[ChillWill]

Well I don't think this is going anywhere.

To the op, my opinion is, if you're doing a recipe that has 1/4lb special grain then stick with that and adjust your base malt to hit your og unless you're efficiency is wildly different, in which case that's probably the least of your worries. Done.

 

[Bmorebrew]

To the op, my opinion is, if you're doing a recipe that has 1/4lb special grain then stick with that and adjust your base malt to hit your og unless you're efficiency is wildly different, in which case that's probably the least of your worries. Done.

Scale everything. I'm not going to beat the dead horse here - I could offer more evidence or a different analogy, but even ChillWill says himself it's not going anywhere.

If you are only off by a couple of points, for example your BE is 67%, you're close enough that you don't need to add base malt. Don't change anything. If it's 89%, that's another story. I am a chemist, and I'm saying if you need to adjust to hit numbers, scale everything.

 

[ultravista]

OK, well I now have my answer ...

I plan on brewing the recipe as-is and will compensate for higher efficiency post boil. Going from 65% yo 75% isn't that much more expensive. It can all fit in a 6.5 gallon fermenter either way.

I may just end up with more that can fit in the keg. I'll bottle it I guess.

Or I could leave the higher OG and have a stronger ABV post-ferment.

The BYO Rogue Shakespeare Stout recipe (via Jamil) is 1.062 @ 65%. At 75% it jumps to 1.071 and the ABV follows.