I never calculate mash/sparge water volumes but I think I should

[TravelingLight]

Bear with me, guys, I think I need some schooling...

I just brewed my fourth beer, my second all grain batch. My third beer (first AG batch) was brewed with a buddy who's been brewing a while so I just kind of followed his lead. I repeated much of the process when I brewed this beer (saison) but I was on my own.

Grain bill for the saison: (5 gal batch)
11# Pils
1# Wheat
1# Vienna

To mash, I heated 10 gallons of water to about 152 (target mash temp = 148). Mashed for 60 mins. Vorlaufed a few times until I was satisfied, then drained to the kettle. This gave me a boil kettle (BK) volume of about 6.5 gallons. I wanted about 7 gallons in the BK to compensate for boil off, and because I'm pulling a gallon off after primary to pitch dregs so I wanted a little more than 5 gallons. Meanwhile, I was heating about 7 gallons of sparge water to 170 degrees. Dumped that into the mash tun to cover the grains, vorlauf, then drain to BK, but only about a half gallon because I only wanted 7 gallons preboil. My preboil gravity was 1.044. My calculations (at 65% efficiency) had OG at 1.050. My actual OG post boil and post chilling was 1.052.

What am I doing wrong? For starters, I need to calculate water volumes, right? I'm assuming not everyone uses the same amount of water for mash and sparge. Again, I was just doing it this way because it was my first AG by myself and I was just doing what my buddy did before.

Also, why did my OG come out higher than my calculations? Thanks for any advice. I'm just trying to dial my process in and be a more efficient brewer.

 

[str1p3s]

i'm confused... you mashed with 10 gallons of water? how big was your mash tun to fit that plus the grains? and how did you only end up with 6.5 after draining 10 gallons of water? and then used another 7? I'm still confused exactly how this worked, but if you used 17 gallons and only drained 7 gallons of it, a lot of your sugar would be deluted in the 10 gallons you wasted.

unless I'm missing something obvious which is totally possible. i've only done 11 batches myself.

 

[thedon986]

You used 17 gallons of total mash/sparge water for a 14# grain bill???? Wowzers. Should be roughly half that for a 5 gallon batch, after adjusting for dead space, beer left in fermenter, etc.

Definitely have to calculate your water volumes, I've never not calculated them with all-grain. I just brewed an IPA with a little over 17# of grains and mashed with 5.5g and sparged with 4g (I think?), with tons of hop debris/trub left in the BK I have over 5 in my fermenter.

You want to calculate your water volumes so you don't sparge with 7 and only use .5 of the sparge water. Think of all that delicious fermentable wort you left behind.

 

[Pappers_]

Congrats on your first few beers and your second all-grain - it will get easier and not seem as puzzling after you do a few more of them. Honestly, if you were within 2 points of your targeted OG, that is well within my margin of error - well done!

I'm like you, I do kind of 'rustic' version of all-grain brewing, what @Denny (Denny Conn) says is easy all-grain brewing. Technically, its called Single Infusion Mash with Batch Sparging. I have a few thoughts for you:

1. 10 gallons of water in 13 pounds of grain is going to give you a thin mash. Generally, as I understand it, a thin mash dilutes the concentration of the enzymes and slows the conversion process, as well as results in a wort with a greater percentage of simpler sugars which means a more fermentable wort.

2. Did you measure the temperature of your mash? I'm curious about how close you came to 148F. I use BeerSmith to calculate my mash-in numbers: how much water at what temperature added to what amount of grain to get to my target mash temp. Generally, it does a good job and gets me to the right mash temp using my single infusion method.

3. While I calculate the mash water volume, I do not calculate the batch sparging volumes, its unnecessary. Like you, I mash out and then measure what my actual volume is. Subtract that from the pre-boil volume I know I need based on the system I use, I divide that by two and use that amount for batch sparging, twice. In other words, two equal volumes of sparge water.

Hope this helps!

 

[jerbrew]

Non of this makes sens to me. You should start measuring your water. You had a grist/water ratio of almost 5L/lb? That's not right and incredibly high. For example, I just brewed a 13# grist and used about 8 gallons total for mashing and sparging. came out with 7 gallons in the kettle. Something is wrong here.

 

[TravelingLight]

Thanks everyone. I knew you guys could set me straight. A couple things I should have mentioned that I just noticed going back over my notes...

No, I did not get all 10 gallons of strike water in the mash tun. I basically filled up the mash tun to within about an inch of the top of the tun (10 gallon orange round cooler). And I definitely had strike water left in the HLT, probably a good 3 gallons or so. With that said, if I actually only used about 7 gallons strike water and got about 6.5 in the BK after first runnings, wouldn't that be about right for water absorption by grain?

I did measure temp on the mash. My target mash temp was 148. When I got the grains in the tun with the water and stirred to break it all up and get it mixed, I checked temp right before putting the lid on for the sacc rest. Temp was right at 148.6ish. After sacc rest, temp was 147. I can definitely live with only one degree loss.

I guess my ultimate questions are...with me doing so much wrong during my mash and sparge, how did I get so damn close to my gravity? Or was it just sheer luck?

 

[pvpeacock]

As others have said, you used way too much water in both your mash and sparge. For a grain bill like that, I do the following:
1. mash with 5 gallons of water heated to the appropriate temperature
2. heat 4-5 gallons of sparge water while mashing is going on
3. drain the mash tun and see how much wort you get (probably 3 - 3 1/2 gallons)
4. add enough sparge water to your mash tun to get the total volume you want to boil in your kettle. Assume you will get most of your sparge water back out of your mash tun since the grains have already absorbed water during the mash. So, if you got 3 gallons of wort after the mash and want 6 gallons total to boil, add another 3 to 3 1/2 gallons of sparge water. Then stir and drain. voila!

I don't really care much about the grain to water ratios for the mash or about any loss in efficiency from doing a single batch sparge as opposed to a double or a fly sparging. My method is simple, easy and makes good beer.

 

[TravelingLight]

As others have said, you used way too much water in both your mash and sparge. For a grain bill like that, I do the following:
1. mash with 5 gallons of water heated to the appropriate temperature
2. heat 4-5 gallons of sparge water while mashing is going on
3. drain the mash tun and see how much wort you get (probably 3 - 3 1/2 gallons)
4. add enough sparge water to your mash tun to get the total volume you want to boil in your kettle. Assume you will get most of your sparge water back out of your mash tun since the grains have already absorbed water during the mash. So, if you got 3 gallons of wort after the mash and want 6 gallons total to boil, add another 3 to 3 1/2 gallons of sparge water. Then stir and drain. voila!

I don't really care much about the grain to water ratios for the mash or about any loss in efficiency from doing a single batch sparge as opposed to a double or a fly sparging. My method is simple, easy and makes good beer.

I like this method. When you said "mash with five gallons" did you mean for this recipe or is that always your go to strike volume? Or do you always calculate your strike volume but not your sparge volume?

 

[carvetop]

You could try the following steps to get in the ballpark with volumes:
1) Determine desired pre-boil volume based (mostly) on evaporation during boiling. Let's say 6.5G for a typical 5G batch.
2) Determine an appropriate amount of water to mash with - I use 1.5qts/lb of grain (others will argue but 1.25 - 1.5qts/lb is reasonable). For this recipe that would equal 13lbs of grain x 1.5qts/lb = 19.5 qts or 4.8G of mash water. This will probably need to be heated 10 to 12 degrees F above your strike temp but you'll dial that in as you go.
3) Determine losses from grain absorption and tun dead space. Grain absorbs its weight in water (approximately) so we have 13 lbs/(8.33lbs/gallon of water) = 1.6G loss from grain absorption. Dead space is based on your set up but we'll call it 0.25G for this example.
4) Subtract the numbers calculated in step 3 from your initial mash volume to get your estimated 1st runnings volume: 4.8G - 1.6G - 0.25G = 2.95G in 1st runnings.
5) Subtract this amount from your desired pre-boil volume to calculate the amount of sparge water needed: 6.5G - 2.95G = 3.55G of sparge water needed. I generally heat this water up to 185F - 190F such that, when mixed with the already hot grains the resulting temp is around 170F.

That's my general water volume calc process before I get started. Good luck with the brewing!

 

[pvpeacock]

I don't make big beers, so I'm always using a grain bill of between 10 and 15 lbs. As a result, I just use 5 gallons of strike water to mash with every time. It makes it very simple. I know some people will say that the ratio of grain to water it too high, but it works fine for me.

 

[TravelingLight]

Since I hit my gravity (at least, within the margin of error), did I just get lucky or what??

Also, how do preboil gravities relate to post boil OG? I ask because I've never done a preboil gravity check before. And this one came in at 1.044 (60 degree sample) and the OG was 1.052 (66 degree sample).

 

[pvpeacock]

pre-boil vs. post-boil gravity is basically a function of the evaporation of wort during the boil. As a result, after the boil, you have the same amount of sugar in a smaller volume of wort = higher SG.

 

[laredo7mm]

I don't make big beers, so I'm always using a grain bill of between 10 and 15 lbs. As a result, I just use 5 gallons of strike water to mash with every time. It makes it very simple. I know some people will say that the ratio of grain to water it too high, but it works fine for me.

Sounds about like what I do. Most of my batches are not big beers either, usually in the 1.048 to 1.060 range. I make 6 gallon batches so after kettle trub and ferementer loss, I have at least 5 gallons into the keg.

I mash in with 5 gallons, drain off about 3.5, batch sparge with 3.5, and then start my boil with about 7 gallons. I read somewhere that having equal first and second runnings (volume wise) is a good thing. I don't have any issues either. Consistently hit 75% efficiency.

 

[madscientist451]

I like this method. When you said "mash with five gallons" did you mean for this recipe or is that always your go to strike volume? Or do you always calculate your strike volume but not your sparge volume?

Once you brew 3-4 all grain batches, you should have a pretty good idea of how much total water you need for a 5 gallon batch. You will be accounting for grain absorption and boil off in your kettle. The total water may change if you brew a big beer with more grain, (more absorption) or go with longer boil times (more evaporation) but once you get a ball park number for a standard 6% abv batch it will stay pretty steady.
I usually use 1.5 qts/lb of strike water and use an on line strike water calculator to get the temperature. I then fly sparge with whatever water is left over, or you can batch sparge.
Its a waste of time to heat 10 gallons of strike water when you need less than that. But everyone has their own way, you'll find the method that works best for you.

 

[TravelingLight]

Thanks everyone for the excellent advice. I'm brewing my football tailgating beer soon so I will be much more efficient this time around.

 

[55x11]

You could try the following steps to get in the ballpark with volumes:
1) Determine desired pre-boil volume based (mostly) on evaporation during boiling. Let's say 6.5G for a typical 5G batch.
2) Determine an appropriate amount of water to mash with - I use 1.5qts/lb of grain (others will argue but 1.25 - 1.5qts/lb is reasonable). For this recipe that would equal 13lbs of grain x 1.5qts/lb = 19.5 qts or 4.8G of mash water. This will probably need to be heated 10 to 12 degrees F above your strike temp but you'll dial that in as you go.
3) Determine losses from grain absorption and tun dead space. Grain absorbs its weight in water (approximately) so we have 13 lbs/(8.33lbs/gallon of water) = 1.6G loss from grain absorption. Dead space is based on your set up but we'll call it 0.25G for this example.
4) Subtract the numbers calculated in step 3 from your initial mash volume to get your estimated 1st runnings volume: 4.8G - 1.6G - 0.25G = 2.95G in 1st runnings.
5) Subtract this amount from your desired pre-boil volume to calculate the amount of sparge water needed: 6.5G - 2.95G = 3.55G of sparge water needed. I generally heat this water up to 185F - 190F such that, when mixed with the already hot grains the resulting temp is around 170F.

That's my general water volume calc process before I get started. Good luck with the brewing!

good post - I agree. After a few brews you could ball-park it (or adjust slightly depending on grain bill) but I would use a brewing calculator. I like BeerSmith.

 

[GilSwillBasementBrews]

Since I hit my gravity (at least, within the margin of error), did I just get lucky or what??

Also, how do preboil gravities relate to post boil OG? I ask because I've never done a preboil gravity check before. And this one came in at 1.044 (60 degree sample) and the OG was 1.052 (66 degree sample).

To calculate your gravity you would divide your pre-boil volume by your post-boil volume. And multiply that answer by your gravity points. So you'd have (6.5/5.5)x44=52. So pre boil/post boil x gravity points( I.e. 1.044=44 gravity points.)
= post boil gravity points (52 points would then =1.052)