Full volume mash efficiencies?

[BigJay13]

I have a 10 gallon eHERMS system but am starting to develops recipes to move to the pro side in the next few years and am brewing 5 gallons most of the time. My first brew at the 5 gallon size was terrible with really bad efficiencies and I collected way too much wort due to a problem in beer smith. I’m starting to think it would just be easier to do a full volume mash at the 5 gallon size and short the brew day. So what are people getting for mash efficiency when doing that…65% with stirring and recirculating? When I do the 10 gallons I’m getting over 90% typically so I banked on that and got like 50% in back to back brews I did two weeks ago at the 5 gallon size.

 

[doug293cz]

This shows you what should be the differences between full volume (no sparge) processes and sparge processes. Fly sparge is not included because it is difficult to model for specific cases, and impossible to model for the general case. However, some data shows that a good fly sparge will have about a 2 - 3 percentage point increase in lauter efficiency over a triple batch sparge @ 0.12 gal/lb absorption rate.

Mash efficiency is equal to conversion efficiency times lauter efficiency (what's in the chart.) If going to full volume drops your mash efficiency by more than 17 - 18 percentage points when going from fly sparge to no sparge, then you are likely getting lower conversion efficiency - which shouldn't be a function of sparge process.

If you are comparing brewhouse efficiencies, then you need to account for the probability that the post-boil loss percentages are different (larger) for small systems vs. large systems.

Brew on

 

[CascadesBrewer]

So what are people getting for mash efficiency when doing that…65% with stirring and recirculating?

I don't 100% trust my post-mash volume and refractometer readings, but I typically measure around 78% to 80% mash efficiency with a full volume mash BIAB system. Assuming I am not sucking up a ton of wort with hops, I usually measure 73% to 75% overall efficiency (based of volume and gravity into the fermenter).

 

[odie]

there are two parts to deal with.....conversion efficiency and lauter efficiency...

assuming you are crushing finely and mashing long enough at the right temps you "should" be near 100% conversion of starch to sugar.

That leaves lauter efficiency, getting the sugar out of the wet grain and into the kettle ...you don't say what your doing? Just drain? squeeze bag? sparge the bag? etc?

If you collected too much wort then you just boil down to your target volume. But that also means you probably got some extra sugars out of the grain bed so in a way, your efficiency went up...any sugar left in the grain and not in the kettle is lost efficiency.

theoretically you could sparge several times and extract all the sugar, 100%, but then have a lot of excess water in the wort that you must boil out.

 

[Yooper]

I get 72% with a full volume mash in a 5 gallon batch (starting with +/- 8 gallons of water), and a very fine crush.
I started doing that when I went from 11 gallon batches in my 3 vessel HERMS to 5 gallons. It shortens the brew day by quite a bit by skipping sparging and just running off into the brew kettle.

 

[odie]

everything in life is a trade off. Time is money.

You can easily hit nearly 100% mash efficiency...but that entails an extended time mash and sparging until the run off hits 1.000.

But then you will have 10+ gallons of wort to contend with. You will be boiling off excess water for hours before you can start your "boil".

Your savings in grain is lost in time and energy (electric/propane).

 

[beersk]

I think your overall brewhouse efficiency is the important number to focus on. I do full volume mashes for 2.5 gallon batches and usually get between 65 and 70% brewhouse efficiency. I start with around 5 gallons of water (for a planned 3.5 gallons post boil, 3 gallons into the fermenter). I did a 3 hour mash recently (I went out and played 9 holes of golf during the mash) and that bumped my efficiency up to about 73%. I guess the extra time mashing helped. But I'm not about to start doing 3 hour mashes.

 

[doug293cz]

I think your overall brewhouse efficiency is the important number to focus on. I do full volume mashes for 2.5 gallon batches and usually get between 65 and 70% brewhouse efficiency. I start with around 5 gallons of water (for a planned 3.5 gallons post boil, 3 gallons into the fermenter). I did a 3 hour mash recently (I went out and played 9 holes of golf during the mash) and that bumped my efficiency up to about 73%. I guess the extra time mashing helped. But I'm not about to start doing 3 hour mashes.

I disagree. For recipe formulation, and hitting a target OG, the mash efficiency is the one that determines the amount of grain required. If necessary, I can provide an example where the same brewhouse efficiency provides different OG's for the same grain bill and batch size, if post boil losses are different and mash efficiencies are different.

Brew on

 

[BigJay13]

Ok I realize I need to give more info…

I have a false bottom that leaves almost 3 gallons below it in the MLT. I typically get about 83-85 brewhouse efficiency and close to 100% mash efficiency when fly sparging a 10 gallon batch. I don’t trust my volume measurements so take that for what it is. However im not usually off by 20 points SG. Usually within a few points.

I want to use the same MLT to do a full volume mash (no bag and normal grain crush) and just run off so I skip the sparge and save time during the brew day to potentially brew more often

 

[Bill Tong]

I disagree. For recipe formulation, and hitting a target OG, the mash efficiency is the one that determines the amount of grain required. If necessary, I can provide an example where the same brewhouse efficiency provides different OG's for the same grain bill and batch size, if post boil losses are different and mash efficiencies are different.

Brew on

It took me a while to realize that the efficiency you specify in Beersmith is brewhouse efficiency. Mine is at 65% and i thought there was something wrong in my mashing.

Then i learned that this includes post boil losses. My mash efficiency turns out to be around 80%. I make 18 litre batches, but i loose 3 litres due to kettle trub, which works out to nearly 15% loss in brewhouse efficiency.

 

[VikeMan]

I have a false bottom that leaves almost 3 gallons below it in the MLT. I typically get about 83-85 brewhouse efficiency and close to 100% mash efficiency when fly sparging a 10 gallon batch.

How close to 100%? Commercial breweries using mash filter presses are getting maybe 98%. Fly sparging can't get near that without making a ridiculous amount of wort.

 

[ScrewyBrewer]

I disagree. For recipe formulation, and hitting a target OG, the mash efficiency is the one that determines the amount of grain required. If necessary, I can provide an example where the same brewhouse efficiency provides different OG's for the same grain bill and batch size, if post boil losses are different and mash efficiencies are different.

Brew on

I build recipes tailored to my brewing system based on the original gravity, final gravity, and volume of beer to keg. Then I look at my brewhouse efficiency and realize how much extra grain I could have saved if the brewhouse efficiency were higher.

But I am aware at the start of the additional cost and do not worry much about it. And getting 78% mash efficiency with 70% brewhouse efficiency is baked into most of my 10-gallon recipes. When doing 5-gallon batches, that is when the brewhouse efficiency is even lower.

 

[Bill Tong]

Ok I realize I need to give more info…

I have a false bottom that leaves almost 3 gallons below it in the MLT. I typically get about 83-85 brewhouse efficiency and close to 100% mash efficiency when fly sparging a 10 gallon batch.

Assuming you have no other losses than the 3 gallons deadspace, working on 83% brewhouse efficiency, it means that 17% of your sugars are contained in that 3 gallons. This means your total volume is 3/0.17 = 17.65 gallons, 3 is deadspace so you collect 14.65 gallons and boil off 4.65?

 

[bobtheUKbrewer2]

I full volume mash (32 litres of water / 10.5 lb grain / BIAB) to get 22 litres of 3.8% pale bitter. No idea what that is in efficiency tems, I mash for 70 minutes, boil for 15 minutes before adding bittering hops for 60 minutes and add 200 gm flavour / aroma hops at flame out, stirring for 10 minutes.

 

[doug293cz]

Ok I realize I need to give more info…

I have a false bottom that leaves almost 3 gallons below it in the MLT. I typically get about 83-85 brewhouse efficiency and close to 100% mash efficiency when fly sparging a 10 gallon batch. I don’t trust my volume measurements so take that for what it is. However im not usually off by 20 points SG. Usually within a few points.

I want to use the same MLT to do a full volume mash (no bag and normal grain crush) and just run off so I skip the sparge and save time during the brew day to potentially brew more often

Do you really leave (almost) 3 gal of wort behind in your MLT, or is that just the volume under your false bottom - most of which gets drained to the boil kettle? If you really left 3 gal in the MLT, you mash efficiency could not be anywhere near 100%. Mash efficiency is equal to conversion efficiency times lauter efficiency. Three gallons left in the MLT would not affect conversion efficiency, but it would trash the lauter efficiency.

Brew on

 

[BigJay13]

Do you really leave (almost) 3 gal of wort behind in your MLT, or is that just the volume under your false bottom - most of which gets drained to the boil kettle? If you really left 3 gal in the MLT, you mash efficiency could not be anywhere near 100%. Mash efficiency is equal to conversion efficiency times lauter efficiency. Three gallons left in the MLT would not affect conversion efficiency, but it would trash the lauter efficiency.

Brew on

There is 3 gallons under the false bottom and probably a gallon and a half left behind because of the way the port is cut. So in BeerSmith I forgot to adjust for those three gallons making my mash way too thick. I should have mashed in more liquid and sparged less.

 

[beersk]

I disagree. For recipe formulation, and hitting a target OG, the mash efficiency is the one that determines the amount of grain required. If necessary, I can provide an example where the same brewhouse efficiency provides different OG's for the same grain bill and batch size, if post boil losses are different and mash efficiencies are different.

Brew on

I've always just paid attention to my brewhouse efficiency. Sure it matters from system to system, but I think if you know you're going to get 1.050 for 5.5 gallons into the fermenter from 10lbs of grain, then mash efficiency doesn't matter as much as brewhouse efficiency. Maybe for a pro mash efficiency matters more, but maybe not so much for a homebrewer brewing 2.5 or 5 gallon batches. Then again, I guess if you get totally shite mash efficiency, it's going to throw off your brewhouse efficiency...but I pick one and brewhouse efficiency is the one I focus on.

 

[crazyjake19]

I do full volume mash for 4.25 gallon BIAB batches and my mash efficiency is a solid 68%. I'm sure it's on the low end of the scale but it's absolutely consistent from batch to batch and I care more about consistency and recipe design than messing with my mill (cheap $22 Corona mill) and trying to squeeze out a few more points of efficiency.

 

[Alan Reginato]

Full mash, BIAB, 30 L (6,6 us gal). Usually 6 to 7 kg (13 to 15 lbs). 22 to 23 L (5,8 to 6 us gal) into fermenter. Close to 70% brewhouse efficiency.

I squeeze the hell out of the grain bag and use another bag to filter the wort, that goes to the fermenter.

It's a good score, but I am looking forward to improve that by ordering a finer grain crush.

Cheers!