Mash Volume Higher than Boil Volume eHERMS

[Town9]

Hello,

I came across a new situation for me during my last brewing session:

I brewed a RIS (Dry Bourbon-Coffee Beaned) with a 32.5 lb grain bill that required about 10.2 gallons of strike water for my desired mash thickness. It was a 5 gallon batch on my 20-gal eHERMS system, and my boil volume was around 6 gallons (I use a steam capture lid). This meant that I collected my boil volume before I drained my mash tun of all the water, so I didn't need to add any sparge water to the top, like I would normally do during my continuous fly sparge.

I decided to drain the MT dry, ending up with a much larger boil volume than planned. This resulted in a longer boil, but my efficiency numbers were way off of normal as was my OG. I RDedDn'tWAHdAHB, and I'm really happy with how the beer turned out so far (just started the dry bean last night).

Question: Should I have done my normal fly sparge instead of draining the MT dry, even though I knew I already had enough wort in the MT to reach boil volume?

I was surprised that I hadn't come across this in the dozens of brew days I've had since I set up eHERMS a few years ago, but I guess I normally do 10 gal batches or have OGs that are a little lower...

 

[odie]

high OG beers like RIS are going to require a long boil time to get down to boil volume. Efficiency drops as the mash gets bigger and bigger unless you sparge well. But then again, you are boiling off a lot of excess water.

You either sacrifice extra grain or time (boil off). Both are costly, either in materials, energy or labor.

That is why higher gravity beers usually cost more when you are at your fav brewery/bar/liquor store

 

[Town9]

high OG beers like RIS are going to require a long boil time to get down to boil volume. Efficiency drops as the mash gets bigger and bigger unless you sparge well. But then again, you are boiling off a lot of excess water.

You either sacrifice extra grain or time (boil off). Both are costly, either in materials, energy or labor.

That is why higher gravity beers usually cost more when you are at your fav brewery/bar/liquor store

Thanks!

I did plan on a longer boil (90 mins instead of my normal 60), but sounds like I should have gone longer.

Should I have planned on a boil volume/time that was equal to the first runnings of my mash? Or even longer to allow a small sparge?

The only problem is that my eHERMS/steam capture system only boils off around 0.2 - 0.5 gal/hr, even with a raging boil. If I do a 120 min boil, the best I can plan for is boiling off 1 gal. Is it common for homebrewers to do a 3-4 hour boil for a RIS?

 

[odie]

I do BIAB. I usually have a total mash volume (grain & water) of around 6-7 gal for a "standard" beer. I do a post mash sparge of 1-2 gallons to hit by starting boil volume of 6 gal.

When I do my RIS, I'm in the low 20s on mash grain. total mash volume is around 14 gal. But I fully drain the bag and sparge some as well and end up boiling off for a couple/few hours to reach my 6 gal boil target.

It sounds like your grain bill is 50% bigger than mine for an RIS. I suppose since you are not collecting your full mash nor are sparging for extra efficiency.

 

[Bobby_M]

32.5 lb grain bill that required about 10.2 gallons of strike water for my desired mash thickness. It was a 5 gallon batch on my 20-gal eHERMS system, and my boil volume was around 6 gallons.

This gets into some pretty thick weeds because there are differing opinions on whether a mash tun ought to be run dry at all during a fly sparge. There's no question about it when calculating a no sparge or batch sparge batch, but with fly it's pretty common to keep feeding the sparge water in "continuously" until the preboil volume desired is achieved. That leaves the mash tun full.
This example is extreme though. You actually performed it as a full volume mash/no sparge.

I decided to drain the MT dry, ending up with a much larger boil volume than planned. This resulted in a longer boil, but my efficiency numbers were way off of normal as was my OG. I RDedDn'tWAHdAHB, and I'm really happy with how the beer turned out so far (just started the dry bean last night).

This is why many people do Partigyle brewing with extreme gravity beers. You could have just collected the wort volume you needed (while sparging) and then continue sparging to collect a whole other batch of low/medium gravity wort for a small beer.

Question: Should I have done my normal fly sparge instead of draining the MT dry, even though I knew I already had enough wort in the MT to reach boil volume?

The sparge would have only derived additional wort at decreasing gravity.

I was surprised that I hadn't come across this in the dozens of brew days I've had since I set up eHERMS a few years ago, but I guess I normally do 10 gal batches or have OGs that are a little lower...

Setup high gravity batches as 90-120 minute boils and it will cause you to make some extra wort for a slightly increased efficiency.

 

[Town9]

This gets into some pretty thick weeds because there are differing opinions on whether a mash tun ought to be run dry at all during a fly sparge. There's no question about it when calculating a no sparge or batch sparge batch, but with fly it's pretty common to keep feeding the sparge water in "continuously" until the preboil volume desired is achieved. That leaves the mash tun full.
This example is extreme though. You actually performed it as a full volume mash/no sparge.

This is why many people do Partigyle brewing with extreme gravity beers. You could have just collected the wort volume you needed (while sparging) and then continue sparging to collect a whole other batch of low/medium gravity wort for a small beer.

The sparge would have only derived additional wort at decreasing gravity.

Setup high gravity batches as 90-120 minute boils and it will cause you to make some extra wort for a slightly increased efficiency.

All of this makes sense, thanks for the in depth response. I’m surprised I haven’t come across this in the past, but I guess the high OG beers I’ve brewed were more in the 1.090s as opposed to the 1.10s