No Sparge math help

YOpassDAmike · Jun 8, 2016

Hello,

I will be brewing an all grain RIS. I will be using a no sparge mashing method. I will be doing a 3.5 gallon batch (post boil volume). The grain bill consists of 15lbs 6.5 ounces of malted barley and 4 ounces of oats. I will be mashing for 60 minutes at 156 degrees. I want my mash thickness to be 1.25qt/gal, and I factored my grain absorbtion to be .96 gal/lb. I will be doing a 120 minute boil. It is projected that my pre boil volume should be 5.7 gallons. With having about 16 pounds of grain in my mash tun, how much water do I need to add to the mash tun to end with a 5.7 gallon preboil volume, thanks guys.

doug293cz · Jun 8, 2016

http://pricelessbrewing.github.io/BiabCalc/. It says BIAB calculator, but it is really a generalized batch sparge volume, temperature, and efficiency calculator. I highly recommend it.

Brew on :mug:

RM-MN · Jun 8, 2016

With that much grain and no sparge batch it screams for a partigyle. You'll be leaving a lot of fermentable sugars in the mash tun.

YOpassDAmike · Jun 8, 2016

RM-MN said:
With that much grain and no sparge batch it screams for a partigyle. You'll be leaving a lot of fermentable sugars in the mash tun.

That's fine, for this beer I am not concerned about leaving excess sugar, any other time I am. I want to get a very thick RIS which has great malt character and is semi sweat. Like a dark lord, thanks.

Gnomebrewer · Jun 8, 2016

15lbs10.5oz of grain = 15.66lbs
Absorption = 0.96gal/lb x 15.66lbs = 15gal
This is obviously not correct. Absorption won't be 0.96gal/lb. Maybe 0.096? I'll assume 0.096gal/lb, so absorption is 1.5gal, which is reasonable for a lightly squeezed bag using BIAB
Water volume = preboil volume + absorption = 5.7gal + 1.5gal = 7.2gal
You can mash with this amount of water, or mash with 1.25qt/lb and add the rest at mashout. That would mean 1.25qt/lb x 15.66lbs = 19.6qt or roughly 5gal of mash water and 2.2gal added at mashout.

As mentioned previously, this is leaving behind a lot of sugar - no-sparge is great for lower gravity beers, but quickly loses efficiency with higher gravity due to the extra grains absorbing extra wort, which is also at a higher gravity.

IslandLizard · Jun 8, 2016

YOpassDAmike said:
Hello,

I will be brewing an all grain RIS. I will be using a no sparge mashing method. I will be doing a 3.5 gallon batch (post boil volume). The grain bill consists of 15lbs 6.5 ounces of malted barley and 4 ounces of oats. I will be mashing for 60 minutes at 156 degrees. I want my mash thickness to be 1.25qt/gal, and I factored my grain absorbtion to be .96 gal/lb. I will be doing a 120 minute boil. It is projected that my pre boil volume should be 5.7 gallons. With having about 16 pounds of grain in my mash tun, how much water do I need to add to the mash tun to end with a 5.7 gallon preboil volume, thanks guys.

Grain absorption is usually around 0.12 gallons per pound, not 0.96.
I would add more oats, at least 4% of the grist.

Even a small dunk sparge of a gallon will help your efficiency enormously. Good squeeze, sparge, another good squeeze.

If you're going to secondary/oak this batch for a few weeks or months, make sure to brew a large enough volume that will fill your secondary fermentor to the top after all your (racking) losses. An intended 3.5 gallon batch brewed may turn out to be a bit skimpy to fill a 3 gallon carboy in the end.

What kind of OG are you aiming at? 1.100?
You're going to need a huge yeast starter and ample oxygenation to finish this beer out. Some brewers brew a Porter or Stout first (or a Blonde Ale) and use the yeast cake for their RIS.

doug293cz said:
http://pricelessbrewing.github.io/BiabCalc/. It says BIAB calculator, but it is really a generalized batch sparge volume, temperature, and efficiency calculator. I highly recommend it.

Brew on

That's a really nice calculator! Thank you for the link.