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Extra wort after mash

Hi all,

Newbie question here. I am planning to start all grain brewing soon, but I have a key question which I cannot find an answer to in my research. I am thinking this is because the answer is simple enough that most people take it for granted while I may be thinking about it too much.

My question concerns the seemingly inevitable extra volume of wort derived from the mash. From what I have read for 5 gallon recipes, it seems a typical mash volume is 1.5 quarts / pound of grain, a typical grain amount in 10 - 12 lbs, and a typical sparge volume is 1.5x the mash volume. My general calculations based on these numbers seem to indicate that more than 5 gallons total wort would always be lautered.

But if my recipe is designed for a 5 gallon brew, and I lauter 6-8 gallons total (mash + sparge), will not my OG be lower than desired due to dilution? Or is this extra volume somehow accounted for given a good extraction effieciency?

Thanks

[quote=“soggycd”]Hi all,

Newbie question here. I am planning to start all grain brewing soon, but I have a key question which I cannot find an answer to in my research. I am thinking this is because the answer is simple enough that most people take it for granted while I may be thinking about it too much.

My question concerns the seemingly inevitable extra volume of wort derived from the mash. From what I have read for 5 gallon recipes, it seems a typical mash volume is 1.5 quarts / pound of grain, a typical grain amount in 10 - 12 lbs, and a typical sparge volume is 1.5x the mash volume. My general calculations based on these numbers seem to indicate that more than 5 gallons total wort would always be lautered.

But if my recipe is designed for a 5 gallon brew, and I lauter 6-8 gallons total (mash + sparge), will not my OG be lower than desired due to dilution? Or is this extra volume somehow accounted for given a good extraction effieciency?

Thanks[/quote]

I’m relatively new at all grain, and I’m admittedly un-precise in all of my calculations, but let me put it this way. I usually start with about 8 gallons of water. After grain absorption, and being too impatient to get every drip of second runnings, I usually end up with somewhere close to 6.5- 7 gallons in the kettle. After boiloff and transferring to the fermentor (leaving off hop sludge), I’m usually around 5 gallons (ish). My efficiency is not great (upper sixties), but is at least predictable. You can be as precise or as sloppy with the process as you want. I figure if I get somewhere in the general vicinity of five gallons of wort within five gravity points of what I was shooting for, I’ve been pretty successful. If you’re a type-a stickler for process and detail, I’m sure my approach will drive you nuts. In practice, if you want to be very precise, you’ll need to do a few runs with your system to dial in any volume loss to grain absorption, boiloff, and trub loss.

http://gnipsel.com/beer/software/beer-software.html

JT’s Mashwater3.3 is a nice stand alone program to help with mash/sparge/boil off/loss calculations.

I appreciate your input uberculture and nighthawk,

but is this really all the community has to say?

Either do not worry too much about it or just let the computer tell you what to do (which are almost the same thing)? With as much all grain homebrewing that occurs everyday surely someone has a simple, reasonable explanation for accounting for excess wort in all grain brews and how it affects gravity?

Software is handy in practice, and I do like the idea of implementing it into my brew routine, but I also like to understand the theory.

[quote=“soggycd”]I appreciate your input uberculture and nighthawk,

but is this really all the community has to say?

Either do not worry too much about it or just let the computer tell you what to do (which are almost the same thing)? With as much all grain homebrewing that occurs everyday surely someone has a simple, reasonable explanation for accounting for excess wort in all grain brews and how it affects gravity?

Software is handy in practice, and I do like the idea of implementing it into my brew routine, but I also like to understand the theory.[/quote]

I hope others do weigh in, but essentially, you use way more water lautering than your final volume. The grain absorbs some of it, and you drain off somewhere between your starting volume and final volume, which is at a lower OG than where you want to end up. After you boil for a while, your volume goes down because of evaporation. Since you are concentrating sugars in the boil, gravity increases. The specifics of how much water stays in the grain and hou much you boil off will vary. Software can give you a good estimate, but you will need to give it a try to see how your system works. Even if you goof on volumes a bit, you will make bee

uberculture has got it right. Since I’m fairly low-tech (by choice) and like to have an understanding of how to figure these things out, I made a spreadsheet for AG brewing. After I enter my grainbill, the spreadsheet calculates the total weight of my grist. The water calculations follow from that. Like uberculture said, I typically use about 8.5 gallons of water, and I end up with about 5.5 gallons of wort.

Here are a few figures that may help you understand where the extra water is going:

Grain absorption: .125 gal/lb
Boiloff varies based on pot diameter, boil vigor, air temperature, and humidity. For me, it’s about .02 gal/minute. It’s about 1.5 gallons for a typical batch of beer.

You also need to factor in any dead space in your mash tun, where some of the wort will be trapped. Mine is virtually zero.

So anyway, you can trust in what uberculture had to say. Still confused? Hope this cleared things up.

Ok sounds good. Thanks yall.

The impression I am getting is that recipes are designed to give the brewer at little extra volume for comfort room, considering water lost to mashing and boiling, without sacrificing gravity. It makes sense that you would rather have a little more wort than necessary/desired than a little less.

Appreciate the help.

Just to chime in a bit here myself. I tend to add an extra 5-7l of water to my process above what my or Beersmith’s calculations give me.

There have been may times that my boil off rate was higher than expected and I ended up with a smaller volume of more concentrated wort than I wanted.

The fermentables you use will give you a set amount of sugars. Your ending volume will determine the SG.

If you are able to calibrate your kettle so you know the exact volume that is in there at any time, you can alter your boil times if needed to adjust final volume to get the precise SG you are looking for.

For me, I like to have a little extra liquid. Boiling an extra 15 min for me seems less of an issue than cutting off the boil earlier than expected (or having to top up with water at the end.)

Plus, if I choose not to make an adjustment, I much prefer a slightly lower gravity than expected, than a slightly higher one. Again, just me.

And just one other point. After my mash and sparge runnings come off, I love to see about 40-50% more volume pre-boil than I am expecting final.

That is I would expect to lose something like 1/4-1/3 my volume from boil off and trub - depending on how long I plan to boil.

All the advice you got so far is sound and really all you can do is trail and error with good notes and make proper adjustments each brew session.

You are always going to want extra wort since you will boil off a decent amount and you will want to enough boiled wort so you can leave the sludge in the kettle after the boil.

Unless you know how much water is left in the tun and your boil off amount your best bet is use the online calculators and beer brewing programs, many free ones that work great, and start from there and take notes on how your system uses water. After two or three sessions you will have your system water amounts good to go.

If you are worried about gravity numbers you can fix that too. If you are under/over by a few points you did really well. No casual homebrewer is going to hit the numbers every single time and are lucky if they do at all.

If you want to bump up your OG without messing with the recipe you can add some light malt extract, sugar, molasses, etc. You want fermentable sugars.

If you are worried about flavors and characteristics of the beer you can increase your grain bill by 10% and keep your target volume the same.

I don’t know if this answers some of your questions but this is what comes to mind when I think of mash, volumes, and gravity readings.

I assume you are asking about extra wort volume because you are going to “fly” sparge? I prefer batch sparging because it completely eliminates this problem. How? Mash in with what ever amount of water you want, then run off the entire volume into your kettle. Measure the wort and subtract this from your desired pre-boil target volume. Add the difference back to the mash. When you run this off you will get exactly that amount back out because your grain is already wet and the dead space is already accounted for. Much simpler and much faster than any other sparge method. NO trial and error, just the perfect volume every time.

That is interesting Duxx. That certainly sounds easy.

Do you still hit your desired OG that way?

[quote=“soggycd”]I appreciate your input uberculture and nighthawk,

but is this really all the community has to say?

Either do not worry too much about it or just let the computer tell you what to do (which are almost the same thing)? With as much all grain homebrewing that occurs everyday surely someone has a simple, reasonable explanation for accounting for excess wort in all grain brews and how it affects gravity?

Software is handy in practice, and I do like the idea of implementing it into my brew routine, but I also like to understand the theory.[/quote]

What do you want to know?

In a perfect world of fly sparging, you sparge until you have extracted the sugar down to a gravity of ~1.010. To avoid tannin extraction IIRC.

With either batch or fly sparging, one has to find the balance between leaving to much sugar behind, and having to boil 2-3 hours to get the volume down. That is where finding “YOUR” efficiency number comes in to play. And using the appropriate amount of grain to match “YOUR” system.

How does to much wort effect the gravity? It depends on “YOUR” systems effecency. If the recipe is designed for 65% and you get 75%, you could possible have 1g more wort and still have the same gravity as the recipe. Or, your gravity could be 10% higher at the same volume of the recipe.

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