how do you adjust/account for lost wort during vessel transfers from kettle to keg?

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odie

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Are we supposed to adjust "5 gal" recipes grains bills to account for the amount of liquids that are lost of is that typically already factored in? How much liquid loss is factored into a recipe? I see some 5 gal recipes mention "boil volume" in excess of 5 gallons, often well over 6 gallons...that's a fair amount of lost grain/beer...

I've never liked the fact that so much beer seems to be wasted/lost every time I transfer...

There is always wort left behind in the kettle (along with all the crap)...

Then beer left in the fermenter every time you rack to another fermenter/keg. either with a cane/siphon or spigot...

I always cry over that lost beer...I've added dip tubes to my kettle and fermenters to try to get as much beer as possible to the end of the process.

I've always measured out a full 5 gal keg, let all my vessels drain out to the spigots, and then reverse transfer all the way to the kettle to determine the starting volume/kettle level at flame out in order to achieve 5 gallons finished product..

It just seems I'm losing an awful lot of potential beer...

Any thoughts of dumping the remains of each stage into large mason jars and letting the last of the beer settle to the top and pouring that off to the next stage? Kinda like when harvesting yeast and settling out the trub? might be worth a pint or 2 for each stage?
 
If you are mashing, the grain holds onto about an eighth of a gallon per pound of grain. Boil loss will vary depending on your strength of boil, humidity, pot, etc. but generally I boil away between a gallon and a gallon and a half in my 60-90 minute boil. Then you have kettle losses and fermenter losses. The best way to determine them is to take accurate measurements (always using the same way to measure*) and good notes. You should be able to dial in just a few beers more than 5 gallons into the keg.

I generally collect 7.5 gallons and boil down to 6 to 6.5 gallons (I go for 6.5 if I am going to be using a lot of dry hops in the fermenter due to losing more in my fermenter). If I have a little left over I bottle prime a few bombers or a flip top growler.

* - I was having issues with my volume fluctuating. I traced it down to a 5 gallon bucket that someone other than me had labeled with gallon marks. I now only use one bucket for measuring and things are consistent. My boil kettle markings are designed to be read at boiling and are designed to leave a half gallon behind in the kettle.
 
The answer to the question is: yes, you are supposed to account for all system losses from end to end. Otherwise your end results will be unlikely to match prediction and that's a pita way to run any brewery.

One should optimize their brew systems and methods to not suffer easily avoided losses, but as that tightens up eventually you hit the point where the effort to get a couple/few more points of efficiency outweighs the minor cost-adder to make up for that small loss. As well, putting the entire batch at risk for those couple/few more points seems imprudent from where I'm sitting...

Cheers!
 
I am not exactly sure what you are getting at. When I create a "5 gal" recipe I usually plan for:

* 6.5 gal pre-boil
* 5.5 gal post-boil (I get 1.0 gal/hr boil off with a medium rolling boil)
* 5.25 into my fermenter (trub, hop absorption, shrinkage)
* 5.0 into my keg

The numbers are not exact (and I probably should adjust more for hops as they can suck up a lot of wort/beer) but I find that if I start with 6.5 gal pre-boil, the other numbers work out close enough.
 
There is always gonna be loss. And in some cases there can be a LOT of loss.

In my experience the principle loss-driver is hops. For a moderate to low hopping rate and a well designed system, getting 95% of your post-boil wort into the fermenter is easily doable, and getting 95% of that fermenter volume packaged is doable as well.

Dry hopping in particular is a huge volume killer. For really heavy dry hop loads I've been it knock 20% off my packaged volume. I've heard home who dry hop at exorbitant rates losing upwards of 40%
 
I'm not too concerned with pre-boil since I add water as needed during boil or just before flameout to be at the correct level to yield 5 gal at the keg. I don't even know how much that is since I have a mark on my kettle that will result in 5 gal at the end based upon the kettle draining to the spigot and then fermenter draining to the spigot. but what's left in both the kettle and ferm still add up to a few bottles "after" the trub and yeast and all settle out.

if your at 5.5 post boil that's not bad....4 pints lost

in the past I've often tilted the kettle and ferm AFTER draining and let another pint float to the top for a second spigot draining...and I usually end up having to bottle a couple after the keg is full.

Also, I seem to lose very less than expected during boil, guess my lid is pretty efficient?
 
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if your at 5.5 post boil that's not bad....4 pints lost

Not really. 5.5 gal of boiling water is not 5.5 gal of 70F water due to shrinkage. That 5.5 contains hot break, cold break, and hops that nobody wants into their keg/bottles. Dry hops will soak up liquid as well. I am not going to waste time and effort to squeeze the last drop of murky wort/beer out of my hops and trub. You seem to be adding unknown quantities of water to dilute your beer and then poking fun at people that actually measure and plan their brew process and volumes.
 
Boiloff rate is highly system dependent. It's partially just scale, but homebrewers usually boil off a LOT, often well more than necessary.

I'm typically less worried with the packaged volume than I am hitting my numbers, so I worry about post-boil wort and the rest I just make assumptions based on experience- as someone else posted above if I hit 11 gals post boil, I'll lose approximately 0.5 gals in the kettle and 0.5 gals in the fermenter and get about 10 gals packaged for most beers. Depending on how much I hop I'll fudge expectations- for really low hops I might get 10.5 packaged. For really heavily hopped beers, I may only get 9.5 gals or 10 gals in the fermenter and then as little as 8 gals packaged. But the gravity is right, which is my primary concern. If I worry too much about the volume then I start throwing off my gravities.

Now, the potential complication becomes yeast pitching rate. If you're building a starter based on a pitching rate for one volume/gravity and you hit a different volume/gravity, well that's a potential concern. My preference, when possible, is to harvest fresh and pitch fresh, so if the volume is less or more than anticipated I just harvest more or less accordingly.
 
Also, I seem to lose very less than expected during boil, guess my lid is pretty efficient?
It is my understanding that you shouldn’t use a lid during the boil.... there are products that can produce off-flavors that need to escape during the boil and your recipe’s water requirements should be adjusted accordingly to your measured boil-off loss.
 
I guess the issue is that everyone's kettle & fermenter is a little different. depending on how low your individual spigots will drain...everyone is going to have a different amount left behind at each step in the process...and will have to adjust the ingredient amounts accordingly if you are trying to follow a recipe.

Let me ask the question this way....

most of the recipes are written for "5 gallons"...but is that 5 gals into the kettle? 5 gal into the fermenter? or 5 gal into bottle/keg?

And since everyone's equipment is a little different, everyone is going to have more or less residual at each step...Is there an assumed "standard/average" for the volume that remains sitting at the bottom of the kettle/fermenter after transfer?
 
It is my understanding that you shouldn’t use a lid during the boil.... there are products that can produce off-flavors that need to escape during the boil and your recipe’s water requirements should be adjusted accordingly to your measured boil-off loss.

I never thought about that...makes sense...I just figured covered made boiling easier...I've always targeted the amount of boil to achieve 5 gal in fermenter. I have a mark on the kettle that equals 5 gal wort in the fermenter so that's my target post boil.
 
A 5 gallon batch should mean 5 gallons of beer in the end. Everyone will have differing amounts of losses along the way and may have to adjust the recipe to account for them.

For my system, I don't really track each loss. I drain the mash tun and measure with a dip stick how much wort there is. I then know how much water I need to sparge with to get my preboil volume. My kettle/burner boils off 2 gallons per hour which is on the high side. So I need 7.25 gallons to get 5.25 gallons into the fermenter. I move all but maybe a pint of liquid/trub from the kettle to the fermenter. I bag my hops most of the time so I don't lose much to the trub. I also do not use a spigot on my fermenters so I only lose between a pint and a quart to trub.
 
A 5 gallon batch should mean 5 gallons of beer in the end.
exactly what I assumed.

I move all but maybe a pint of liquid/trub from the kettle to the fermenter. I also do not use a spigot on my fermenters so I only lose between a pint and a quart to trub.
That's pretty good and kinda what I would think is a great "target" for efficiency. I'm nowhere near that efficient...yet, unless I can figure a good way to concentrate the slurry at the bottom to pull more clear wort.

I've always tried to slightly tilt my kettle if the wort is still running clear when the spigot stops...but always quit when the slurry starts coming out for fear of "off flavors, etc"...or am I just worrying over nothing and leaving good wort behind?

My "kettle" is actually an old Greek olive oil settling tank that I bought 20 years ago in Crete. But it's BIG, stainless, had a spigot & lib, and the Drachma was uber cheap back then...lol...but it does leave a significant (IMO) volume after draining that I'm trying to reasonably minimize (dip tube finally added last boil).
 
IMO, you can dump the entire kettle, trub and all into the fermenter and you will not get any off flavors. I usually only leave a very little of the thickest behind. I consider my average beer as good or better than most commercial craft beers in the $9 -$12 a sixpack range. I rarely buy anything more expensive than that so I can't compare to those.
 
DMS causes an off-flavor. It's partially attributable to leave your lid on during a boil. It's can be an issue when using pilsen malt.

I don't really think it's a huge problem, but the theory is that you should leave your lid off for most if the boil.
 
IMO, you can dump the entire kettle, trub and all into the fermenter and you will not get any off flavors. I usually only leave a very little of the thickest behind. I consider my average beer as good or better than most commercial craft beers in the $9 -$12 a sixpack range. I rarely buy anything more expensive than that so I can't compare to those.

I feel to disagree with this. If you put something which is not supposed to end up in the beer, in the fermenting beer. I don't feel it will not add a flavor to it. I feel my beers have become more "cleaner" after I stopped dumping a lot of gunk into the fermentor. I can't say that "some off-flavor went away", I just feel like they got brighter and "cleaner". I feel like it would be almost like if you leave a wooden stick in a bottle of water, then pour the water out and taste it.. The other "beer-flavors" in a beer will mask it, but it's a nuance, to me at least.

It might be some people have never noticed a difference because they have always dumped gunk into the fermentor, and feel the beer is great, but to me it became better after not dumping gunk at least.
 
You never take a recipe and brew it 100% like it says. You scale it to your system, which accounts for all losses.
I agree but the recipes never seem to give those details on their system's vessels...I've just always tried to rack/drain off clear liquid as low as I could get before hitting the bottom layer.

I always have this feeling that I'm ending up a little too diluted if I didn't add a little extra grain/water to the boil or wasting grain cause I did but couldn't figure out how to effectively transfer all to the next stage. damn you flat bottom vessels...but they are so easy to work with...lol
 
As far as most *brewing software* is concernes "batch size" is fermenter volume.

It's not a great metric. Either *post boil* volume or *packaged* volume is better.

Because every system is different, even if a recipe didn't list any volumes, you should use grains as percentages, not weights, and scale it based off your system using those percentages to hit the right gravity. I would scale late hops by a oz:gal ratio assuming the batch volume of the recipe is the post-boil volume (unless it says otherwise), and then adjust any bittering hops based off your system and all the hop alphas to hit the same IBUs. Don't change late hop quantities based on different alphas, but calculate them. Account for any IBU change only with the bittering addition.

Then the losses and volumes become irrelevant. You're hitting the control points of the recipe scaled to your system.
 
Indeed they do. You have the OG, and the grist. That's the info you need. Scale the grist to reach the desired OG in your system. Grist should be calculated in percentages. Everything else is sort of just very un-informal.

When scaling other recipes or doing your own ones you should already know your expected efficiency given the grist size you'll be using. After that most of it should be calculated "automatically" for your system if you have a dialed in equipment profile in a software or a spreadsheet or such. Grain absorbtion is also a variable to account for when operating with different grist sizes.

@odie
 
Also, break material contains lipids that can facilitate oxidative reactions.

As far as the science goes, the pathways are there. Whether it makes a difference in the real world, well homebrewers disagree. If one claims their beer is brighter and cleaner once they start leaving break material behind, that would be an explanation. People assume worst case with off flavors and never realize just how prominent oxidation and autolysis are in homebrew, they just don't often reach the wet cardboard or rancid meat levels as often respectively described. In minute quantities they are much more subtle.

If you're using any sort of heat exchange system (plate or counterflow chillers) then clogging risk necessitates leaving break/hop matter in the kettle. Otherwise I suppose it's preference.
 
If you're using any sort of heat exchange system (plate or counterflow chillers) then clogging risk necessitates leaving break/hop matter in the kettle.

This is a great point. Trub and hop particles will absolutely kill a plate chiller. I use several hop baskets and a false bottom in my system to keep them out. This impacts my losses even more, but I account for it by scaling the recipe up a gallon or so.

Using a program like Beersmith will allow you to account for all these variables in your recipes.
 
We have a few that think having the trub in the fermenter is bad. But in all the years I have been on HBT it seems to be minority opinion.
 
I think a little trub is fine, but if you're dumping the entire kettle into your fermenter, there's no way that won't have some impact on flavor. Especially if you do an extended primary and skip a secondary. That's a long time to be sitting on old hops and cold/hot break material.
 
I use a Grainfather and it is designed to somewhat get you 5 gallons or 19 liters, to bottle or keg ( kegs are 5 gallons/9 liters ). The standard batch size on the Grainfather calculator on the website is 23 liters.

I simply increase it to 28 liters,so I can bottle anywhere between 21 and 24.5 liters ( recipe dependent ). I always whirlpool and leave the wort to rest enough, so I never transfer too much trub. I end up with o.5 inches of trub max.
 
[QUOTE="thehaze, post: 8483754, member: 243739" so I never transfer too much trub. I end up with o.5 inches of trub max.[/QUOTE]

Maybe this is the reason I have no issues dumping the trub into the fermenter. I bag my hops and leave a little of the thickest behind - only about 8-12 ounces. But, I too only get a half inch of trub at the end of fermentation.
 
On my next batch I am going to raise the amount of water I use, add the hops direct and leave the trub to see the difference. If anything, I only expect a small increase in hop presence. Time will tell.
 
I don't bag any hops. They actually help with filtering from the kettle to the fermenter, so they go in loose. So do dry hops.
 
I sometimes use leaf, but my Grainfather has a mesh filter, but the holes are pretty large. When whirlpooling, the sludge - hop debris and grains/husks - will settle nicely at the bottom of the kettle and on the filter, which is also located at the bottom. They will act as an additonal filter, as I always transfer clear wort - as much as it can be clear out of the kettle - thus, minimizing the amount of trub in the fermenter. If I don't dry hop, I will only have a max. 0.5 inch layer of trub.
 
I never heard of or considered a kettle filter...guess since I was happy with my kettle I never paid attention...I've always just let everything settle to the bottom while the wort chiller did it's thing and then opened the spigot and poured off the clear elixer. I do have the spigot pour into a funnel with a fine screen to catch any crud...

are the filters used in kettle similar to the ones in the mash tun? well I've seen several diff types used in mash tuns...lol...i guess a hundred ways to do it...
 
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I start with 8.5 gal total distilled water. The grain drinks ~ a gal in the mash, I lose ~ a gal in the boil, and I leave ~ a gal when the trub cone hits air and collapses ending up with 5.5 gal in the fermenter. I rack 5 gal into a keg.

My recipe is for 5.5 gal in the fermenter. I shoot for 70% brewhouse efficiency and normally hit within a point or two plus or minus.
 
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Not really. 5.5 gal of boiling water is not 5.5 gal of 70F water due to shrinkage. .

true...and something I never thought about when marking my kettle for my target starting volume...I need to measure the kettle water level cold and then again at 212 and see what the diff is...since the target is 5 gal cold beer at the end I need to factor in that plus all the losses below the spigots at each stage.

I just added a SS pipe elbow/dip tube to the inside threads of the spigot...so now I've only got about 2 quarts of muck and missing wort remaining in the kettle once it drains. Not as good as your .25 gal "kettle draining efficiency" (I'm jealous) but definitely better than my past boils

I'm letting it sit in a jar to watch how it settles out. pretty quickly almost half the jar settled to decent looking wort. maybe 2-3 pints there in total if it sits long enough. does anyone screen/filter the slurry at the bottom of the kettle that falls below the spigot? I figure I could put it in my big screened funnel and probably score another pint+ of decent wort while the fermenter is cooling off and waiting for the yeast.
 
One thing that I noticed yesterday, for the first time, was that the volume of boiling water is higher than the volume of non-boiling water. I guess it makes since that all those gas bubbles take up space. I measured my boiling wort and was 0.1 gal above my target...turned off the heat and measured again and was now 0.1 gal below my target.
 
I wait until the surface is smooth before measuring the waterline. But since the wort is just below 212 it's expanded a lot...so if I'm at my target level to achieve my desired fermenter volume and subsequently desired keg volume (5 gal)...well it's gonna shrink.

as far as hitting the recipe points...that comes down to matching the original post-boil volume & ingredients to hit that desired OG. What is the author's post-boil vol?

once I know that vol I can adjust their recipe to the losses/gains my system has between vessels and hit 5 gal at the end and be faithful to the recipe.
 
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