A question about sparge water temperature.

[OHIOSTEVE]

I understand the strike water temps, but a post in another section of the forums got me thinking about my process. I try to always do a bouble sparge for better efficiency.... meaning if I need 4 gallons more in the brew pot for preboil volume, I will split that into two runs of 2 gallons each for ten minutes each... That said I always use 185+- degree water for my sparging. I know the FIRST time through I am under 170 degrees But adding 185 degree water the second time through SHOULD get me over 170 ( which I THINK is where some bitterness may occur?) I have ( as does the poster in the other thread) some issues with bitterness that is NOT hop bitterness. Now in every beer but it is there in a few. Could the high sparge temp be the issue or am I doing it properly?

process is all grain...mashing in a converted cooler with a copper manifold. vorlouf ( which I really do not get) and drain into the boil kettle. boil for the allotted time , cool quickly ( usually between 15-20 mins) open the valve into the fermentor ( glass) and immediately into a swamp cooler. 3-4 weeks in primary at low 60's then into secondary and immediately into cold crash for 2-3 days then batch prime and bottle via revvys thread method.

 

[bob1852]

It could be. But I wouldn't neccissarily call the possible tannin extraction you get from a 170+ grainbed "bitter" (if you are actually getting your grainbed above 170 with the second sparge - have you measured that?)

Try this - a single batch sparge with your ~185 degree water. That's what I've been doing lately based on some of the stuff denny conn and others have posted. It doesn't seem to effect efficiency much at all, and saves some time and effort.

 

[Newbeerguy]

Could be. I have noticed when I used hotter sparge water (hotter than 180) I had some astringincy problems. I too double batch sparged. My suggestion is to sparge with a little lower temp. I went down to 170 and still got 80% eff. So my eff stayed the same and I didn't have anymore problems with bitterness/astringincy.

BTW you say you don't get the vorlauf? All it's meant to do is clear the wort going into the kettle, so your not boiling a whole bunch of grain particles (that will impart tannins into your finish product).

 

[OHIOSTEVE]

It could be. But I wouldn't neccissarily call the possible tannin extraction you get from a 170+ grainbed "bitter" (if you are actually getting your grainbed above 170 with the second sparge - have you measured that?)

Try this - a single batch sparge with your ~185 degree water. That's what I've been doing lately based on some of the stuff denny conn and others have posted. It doesn't seem to effect efficiency much at all, and saves some time and effort.

when I only do a single sparge my efficiency goes in the toilet....no idea why.

 

[Newbeerguy]

when I only do a single sparge my efficiency goes in the toilet....no idea why.

Do you stir it like crazy? Try mashing a bit thicker, leaving some more water to sparge with.

 

[OHIOSTEVE]

Could be. I have noticed when I used hotter sparge water (hotter than 180) I had some astringincy problems. I too double batch sparged. My suggestion is to sparge with a little lower temp. I went down to 170 and still got 80% eff. So my eff stayed the same and I didn't have anymore problems with bitterness/astringincy.

BTW you say you don't get the vorlauf? All it's meant to do is clear the wort going into the kettle, so your not boiling a whole bunch of grain particles (that will impart tannins into your finish product).

I understand the purpose of the vorlouf just not sure I am doing it properly I guess. My beer has few if any grains in the boil so I am getting the job done but I see peopel talking about easing the valve open and leting it run slowly until it is clear then opening the valve... I open it slowly to avoing packing the grain bed, but I open it all the way up and run between about a half gallon and a gallon then pour that back in the tun. the wort does not get " clear" but it has very little grain bits in it.

 

[OHIOSTEVE]

Do you stir it like crazy? Try mashing a bit thicker, leaving some more water to sparge with.

Not until recently. I was putting the grain in.. stirring to make sure everything was wet then cover.... Now I stir the crap out of it lol. I am only doing 1.25 qts per pound of grain as is. When I do a bigger beer however there is not enough sparge water needed to even do a double sparge. Maybe I can get by with 1 qt per gallon on bigger beers? My efficiency on an average grain bill is over 75% .. On a big grain bill I hve dropped as low as 57-58% just due to not being able to double sparge I belioeve. I have even thought about running some of the collected wort back through with fresh sparge water.

 

[bob1852]

Try a thinner mash (i.e. hopefully increase mash efficiency but for sure eliminating the teeniest of dough balls) and a single sparge.

It has seemed to work for me. Of course, your mileage may vary....

 

[Newbeerguy]

Not until recently. I was putting the grain in.. stirring to make sure everything was wet then cover.... Now I stir the crap out of it lol. I am only doing 1.25 qts per pound of grain as is. When I do a bigger beer however there is not enough sparge water needed to even do a double sparge. Maybe I can get by with 1 qt per gallon on bigger beers? My efficiency on an average grain bill is over 75% .. On a big grain bill I hve dropped as low as 57-58% just due to not being able to double sparge I belioeve. I have even thought about running some of the collected wort back through with fresh sparge water.

Yeah I wouldn't go much thicker than 1.25 qts/lb. I typically stir the mash every 20mins. During that time I also check the temps to make sure that they are still good. You seem to got the vorlauf down good...it won't be clear, but will not have bits of husks/grain particles floating in it. After I vorlauf then drain I'll put in my sparge water and stir for a good 4/5 minutes. Then vorlauf again and drain.

Perhaps it's your crush? Are you crushing your own grains?

 

[dzlater]

............. On a big grain bill I hve dropped as low as 57-58% just due to not being able to double sparge .....................................

I am a little confused by this.
When I brew a bigger beer I have to do a double batch sparge, because the grain takes up too much room in the mash tun. Smaller beers I can do a single batch sparge, because the grain takes up less room, allowing the full amount of water in a single sparge.

 

[Yooper]

I am a little confused by this.
When I brew a bigger beer I have to do a double batch sparge, because the grain takes up too much room in the mash tun. Smaller beers I can do a single batch sparge, because the grain takes up less room, allowing the full amount of water in a single sparge.

It's because you're limited by the boil volume. What I mean is this- in a 10 pound batch, you can use 1.5 quarts of water per pound of grain, and still be able to sparge with up to .5 gallons of water, without overflowing your BK.

But if you've got a 20 pound grain bill, you can't use as much sparge water per pound, because then you'll have way too much liquid in the BK, and have to boil for three hours to get down to 5 gallons. Does that make sense?

That's why my efficiency drops, too, in bigger beers.

 

[dzlater]

It's because you're limited by the boil volume. What I mean is this- in a 10 pound batch, you can use 1.5 quarts of water per pound of grain, and still be able to sparge with up to .5 gallons of water, without overflowing your BK.

But if you've got a 20 pound grain bill, you can't use as much sparge water per pound, because then you'll have way too much liquid in the BK, and have to boil for three hours to get down to 5 gallons. Does that make sense?

That's why my efficiency drops, too, in bigger beers.

I am still confused. Isn't the boil volume the same whether you are brewing a 1.090 beer or a 1.040 beer?
More grain=less space for sparge water

 

[OHIOSTEVE]

I am still confused. Isn't the boil volume the same whether you are brewing a 1.090 beer or a 1.040 beer?
More grain=less space for sparge water

If you are doing a big beer, the initial run off from your mash will be way more than the initial run off from a small beer. For example, a 10 pound grain bill at 1.25 qts per pound will be approximately 3 gallons and 1 pint of srike water. if I lose my normal amount to absorption that will leave me about 2 gallons of run off, give or take a quart. So I will need 4-4.5 gallons of sparge water to hit my preboil volume ( depending on inside or outside) So I can do a 2 gallon sparge then a 2.5 gallon sparge....... On the other hand lets say I have a 25 pound grain bill and I use the same formulas I will have almost 8 gallons of strike water which will give me an initial run off of about 4.5 gallons, so I only need 1.5-2 gallons of sparge water.... no way I can double batch that.

 

[AnOldUR]

20lb grain bill @ 1.25 qts/lb = 25qts mash-in water
20lbs grain w/ .5qts/lb grain absorbsion = 10 qts water loss
25qts - 10qts = 15qts first runnings (no mash-out)
24qt boil volume - 15qts first runnings = 9qts for sparge or mash-out

10lbs grain bill @ 1.25 qts/lb = 12.5qts mash-in water
10lbs grain w/ .5qts/lb grain absorbsion = 5qts water loss
12.5qts - 5qts = 7.5qts first runnings (no mash-out)
24qt boil volume - 7.5qts first runnings = 16.5 qts for sparge or mash-out

Less sparge water = Less efficiency !


edit:
Oops! left out dead space, but you get the idea?

Steve types faster than me. :cross:


and all your numbers will vary according to your system.
(grain absorbsion, boil-off, dead space . . .)

 

[dzlater]

Maybe I am an idiot or just think about this in my own convoluted logic but:
If I want 6 gallons preboil, with a 7lb grain bill
I need 6.91 total gallons of mash and sparge water
after the grain absorbs the water I will have 3.32 gallons available in the mash tun. That would be the max sparge water that would fit.
6.91-3.32=3.59 that's my mash amount.
(3.59*4) / 7=2.05 quarts per lb
so I know both my mash and sparge will fit they are close to equal and I get my final volume.
If I have 10 lbs of grain for he same batch size I would need a total of 7.3 gallons.
I will have 2.6 space available for sparge water, after the grain absorbs the mash water.
7.3-2.6=4.7
(4.7*4)/10=1.88 quarts per lb
That won't fit in my mash tun, but if I lessen the mash water amount then the sparge won't fit in a single batch.