Difficulty hitting target BG and OG in high gravity brewing

[Chris-18]

Hey all,

So this week I tried to brew 2 beers with gravity above 1.080 each, last one was 1.100.
However I seem to have problems hitting both the target boil gravity and original gravity.
The last beer I made had a target OG of 1.118 and I only managed 1.100. This beers recipe required both muscovado sugar and honey, so the OG would be massive either way, but I was still several points short of where I wanted it to be.
The other beer was supposed to have an OG of 1.084 but I ended up with 1.075. It's not a disaster, but I can't really figure out why I can't hit the target with these high gravity beers. I don't have any problems with gravity below 1.055 say.

I am thinking that either my amount of mash water is too low, and the mix is over saturated with sugar from the grain (possible?) or maybe I am not using enough sparge water. Or maybe it's something else?

Any of you guys have tips for high gravity brewing?

 

[Sadu]

My understanding is that you should expect a bit lower efficiency on high gravity beers since you have less sparge water available. Then build your recipe with the lower efficency in mind.

I got 78% efficency on my RIS where I normally get low 80s on a normal beer. This was biab with batch sparge.

 

[Kent88]

What water to grist ratio are you using? Are you sparging until you hit runnings of 1.011 or 1.010? Do you perform a mash out? What temperature water are you sparging with? Do you treat your water with anything like gypsum, pH stabilizers, or other brewing salts?

I've heard it can be pretty tough to get good extraction for a high-gravity all-grain beer. For the couple of stronger beers (still lower than yours) I've usually kept some DME on hand. I just max out (but I still don't "pack" the mash, I shoot for having space for a ratio or 1.75:1 water:grain) the grist for my mash tun and, rather than calling it a partial-mash, I call the batch a partial-extract.

But if you insist on completely all-grain, then if you have a big enough kettle or mash tun, or you are willing to make less volume of your strong beer, I'd recommend you try parti-gyle. Either that or be prepared to sparge to a high volume of wort and then boil for an extra hour or two.

 

[Chris-18]

What water to grist ratio are you using? Are you sparging until you hit runnings of 1.011 or 1.010? Do you perform a mash out? What temperature water are you sparging with? Do you treat your water with anything like gypsum, pH stabilizers, or other brewing salts?

I've heard it can be pretty tough to get good extraction for a high-gravity all-grain beer. For the couple of stronger beers (still lower than yours) I've usually kept some DME on hand. I just max out (but I still don't "pack" the mash, I shoot for having space for a ratio or 1.75:1 water:grain) the grist for my mash tun and, rather than calling it a partial-mash, I call the batch a partial-extract.

But if you insist on completely all-grain, then if you have a big enough kettle or mash tun, or you are willing to make less volume of your strong beer, I'd recommend you try parti-gyle. Either that or be prepared to sparge to a high volume of wort and then boil for an extra hour or two.

The last one was actually a Mikkeller Black Hole clone - he (Mikkeller) is quite specific that you must use around 2,5-3 liters of water pr. kg of malt in the mash. These batches have only been about 10 liters, as I am experimenting and don't want to waste a ton of material if I screw it up.
So I have around 3,7 kg of malt and use roughly 9 liters of water for the mash and then sparge up so I end up with roughly 12,5 liters of wort pre boil. He also says you must recirculate for quite a while.

I don't use any additives in the water (yet), as our water quality and composition is actually exceptionally good around here.

Curiously he also says that you should stick to 60 minutes of boil time. But I know that you can get a higher gravity if you boil longer. But then I assume you don't add the bittering hops until later? If you boil for say 2,5 hours, and the recipe calls for the first hop addition at 60 minutes, then you wait for that mark - right? Or can you boil the bittering hops for the same amount of time?

Like you say, I actually ended up adding 500 grams of DME to the boil to hit the 1.100 gravity - so maybe there is some efficiency issue I need to figure out.

 

[Qhrumphf]

If you're normally brewing beers in the 1.055 range and trying to hit 1.100, yes, you're going to see an efficiency change.

Look at it this way. You could take 20 lbs of grain, and make 5 gallons of English Barleywine. You could take the same 20 lbs of grain and make 20 gallons of English Bitter. Exact same grain weight, different batch sizes for different gravities. You'll get far, far higher efficiency with the latter because all that extra brewing water is being used to rinse out the grains.

Essentially, more water equals higher efficiency as more sugar gets extracted.

The end logical conclusion is that unless you use the same ratio of grains to water overall (not just mash but sparge included), you're going to see a reduction in efficiency for higher gravity beers and a boost in efficiency for lower gravity beers. To reach the higher gravities, you'd then have to boil off all that additional water.

Most of us don't want to do that for obvious reasons. So your two options are to accept and account for lower efficiency, whether planning the recipe around lower efficiency or keeping DME on hand to adjust, or as another poster mentioned, do a partigyle. Of course, this won't immediately help you get the same batch size and gravity out of the same grain bill, you'd typically aim for slightly smaller batch big beer at your target gravity, plus a whole second batch of beer to go with it. However it does allow you to get maximal extraction from the grains.

 

[Kent88]

So you are sparging to a certain volume, that can lead to efficiency issues with big beers (under-sparging), and tannin off-flavors in small beers (over-sparging). If you can, keep an eye on the gravity of the wort you collect as you sparge.

Curiously he also says that you should stick to 60 minutes of boil time. But I know that you can get a higher gravity if you boil longer. But then I assume you don't add the bittering hops until later? If you boil for say 2,5 hours, and the recipe calls for the first hop addition at 60 minutes, then you wait for that mark - right? Or can you boil the bittering hops for the same amount of time?

If you know your boil is going to last 2.5 hours and you have a hop addition planned for 60 minutes, you wait to add those hops until the wort has been boiling for 90 minutes.

The only issues I've heard about that relate to boiling too long are kettle caramelization or getting too low of a volume. If kettle caramelization is ok for the style of beer you are making, go ahead and sparge until the runnings are 1.011 (but definitely not below 1.010).

Do you perform a mash out? Are you sparging with water that is just a few degrees cooler than 170 degrees Fahrenheit? Doing those two things could also help your efficiency. I think it is possible to over-circulate, if it goes on too long you might lose some heat.

Have you heard about parti-gyling? That is where you use enough grain to brew your bigger beer along with a smaller beer so your first runnings (about the first 1/3 to 1/2 of what you can collect) will be a very high gravity, and you keep that in one kettle and make a big, high-gravity, beer with that, and then you can keep sparging into another, separate kettle and make a small, low-gravity beer with that. You can use this method to make an Imperial Stout and, depending on the grist you use, a Dry Stout, or possibly a Porter, or if you are really tricky maybe a Mild. You just need a big enough kettle or mash tun to hold all the grain and water along with a couple extra kettles and maybe a smaller fermentor for the big beer.

It doesn't really sound like you are having a horrible efficiency issue, these issues plague high-gravity brewers all the time.