Calculating Water properly for my next batch

[inigomontoya]

Hey all I could use a bit of help getting my water amounts done properly for my next AG batch.

I am going to be brewing the 5 Gal version of the Weisenbock out of BCS.

I have 10LBS of Dark Wheat Malt
5LBS Pilsner Malt
2LBS of Munich Malt

I probably will pick up rice hulls today, Not sure how much to get there so if you want to chime in be my guest.

My mashtun is a Keggle with a false bottom, Grain temp is usually around 75-80 degrees (brewing in Phx, it is supposed to still hit 105-107 this weekend)

Mash temp is going to be 152F

90 minute boil

I have seen some calculators that show I will need somewhere around 6.5 gal for mash, and another 3.5 or so for sparge (I do fly sparge, so that may not be accurate).

I just want to make sure that I have enough wort going into the boil to account for the 90 minutes, last time I used the beersmith2 software but not sure if I dialed it in properly and came up short on the water for the sparge and we had to scramble at the last minute and add in more water.

Any help is appreciated, thanks!

 

[kev7555]

As a general rule (seat of the pants brewing) you want to use about 1 liter of hot liquor per lb of malted grain in the mash. This is by no means a hard and fast rule (you could just as easily convert that to one quart per lb of grist and the results will still be fine) but it will get you in the ballpark. As you progress with all grain brewing you will find by consistency alone what works best in your particular mash tun.

I like a consistency that is sort-of like oatmeal breakfast cereal, maybe a bit thinner. I never measure my hot liquor, just keep adding it as I add grain and stir well during the entire process. I like to hit a strike temperature of around 153F for most styles and I just keep taking temperature readings throughout the mash as I'm proceeding, until my temp is close. I hope this helps!

Cheers!

-Kev

 

[Jakemo]

Google "green bay rackers," it's a website with a handful of calculators for total mash water, temp, etc. I won't go into explaining different mash consistencies (1.25qt/lb vs 1.5qt/lb, etc), but that's a good place to start

 

[inigomontoya]

If I add in a couple of pounds of rice hulls do I need to account for any sort of absorbancy that they might add?

 

[Jakemo]

I think just volume.I don't think they absorb to much, otherwise there wouldn't be a point to adding them. But don't take my word for it

 

[BBL_Brewer]

The two factors you need to pay close attention to when doing your next few batches is to figure out how much water your grain is absorbing and how much you loose to the boil in evaporation. Once you get a handle on these, figuring out how much water to run throught the mash tun is a lot easier.

 

[ajf]

You forgot the Special B, Crystal, and Chocolate malts. That should bring you up to 18.25 lbs grain. If you use 6.5g for the mash, you should collect a bit over 4g wort (less whatever dead space you have in the Tun). With 3.5g of sparge water, you should end up with approximately 7.5g pre-boil which is about right for a 90 minute boil with my system. I don't know what effect rice hulls would have because I've never used them, but they will certainly absorb some water. I'd prepare about an extra gallon of sparge water just in case. It's better to have a bit extra rather than not enough.

Good luck.

-a.

 

[JuanMoore]

If you're going to use rice hulls, you only need a few handfuls for a 5 gal batch. A pound or two is way overkill. They aren't even really necessary, but can help prevent a stuck sparge when mashing high quantities of huskless or high protien grains like wheat, rye, or oats. You can soak the hulls in water for a few hours before using them to prevent them absorbing mash water and throwing your volumes off.

 

[inigomontoya]

AJF- Thanks for noticing that!!!! I had forgotten them, went by the LHS to pick up the specialty grains. I am not used to using the BCS book and forgot to look at the original recipe.

I picked up .5LBS of the rice hulls, since they weigh nothing I figured they would be cheap insurance.

Thanks everyone for your input, Cheers!

 

[dzlater]

CAN I MASH IT

( QUARTS PER LB * LBS GRAIN ) / 4 = GALLONS MASH WATER

GALLONS MASH WATER + (.09 * LBS GRAIN ) = VOLUME IN MASH TUN

WATER VOLUMES

PREBOL VOLUME + ( LBS GRAIN * %ABSORBTION ) = TOTAL WATER

(%ABSORBTION I USE IS 0.13 )

TOTAL WATER - [ ( QUARTS PER LB * LBS GRAIN ) / 4 ] = SPARGE
WATER

VOLUME OF GRAINS AND ABSORBED WATER AFTER DRAINING MASH TUN

LBS OF GRAIN ( .09 * ABSORB%) = VOLLUME OF WET GRAIN
I USE THIS TO DETERMINE HOW MUCH ROOM I HAVE FOR BATCH SPARGE ADDITIONS This will vary somewhat depending on kernel size, crush, etc. But it should be a decent starting point. Once you've drained your first runnings, it will over-estimate because of the soluble extract you've removed.

STRIKE WATER TEMP

[ ( 0.2 / QRTS PER LB ) * ( MASH TEMP - GRAIN TEMP ) + MASH TEMP ] = STRIKE WATER TEMP

THIS DOES NOT TAKE INTO ACCOUNT HEAT LOSS DUE TO MASH TUN THERMAL MASS