Hybrid sparge - no sparge help

[hoey222]

I tried to do a modified no sparge (which is really a sparge). Instead of mashing with the total boil volume, I hold a gallon or 2 back. Then I take most of my first runnings then sparge with the remaining gallon at 170 and take the remaining runnings.

I did it yesterday with a 12 pound grain bill and I hit my targets no problems. Mashed at 156 for an hour. I mashed with 7 gallons. Then rinsed with 1.5 gallons.

I did it today with a 15 pound grain bill and completely missed. I was under by more than 10 points. I mashed with 7 gallons and rinsed with 2 gallons.

My "rinse" is to add 1.5 or 2 gallons of boiling water to my grains to bring it up to 167-170. Stir and let it sit for 10 minutes and collect.

What did I miss that today's batch was under target?

Thanks

 

[acidrain]

Were these both the same recipe's?
If not, were both recipe's based on the same efficiency and equipment profiles?
If not, there's your differences.

 

[hoey222]

Different recipes. But same profile and efficiency. I have beer smith and was trying to follow that.

 

[mongoose33]

Did you stir partway through the mash and then again with the sparge? Any difference in technique?

 

[doug293cz]

You'll lose about 4 - 5 percentage points in mash efficiency going from a 12 lb grain bill to 15 lb for the same pre-boil volume. So, that's one reason that the larger bill came out under target. You need to adjust your efficiency expectations based on grain bill size.

Brew on

 

[hoey222]

I guess I was hoping that beer smith would help me estimate my efficiency. I think I need to work on calculating and estimating my efficiency. The only thing I did different was stir the mash with the larger grain bill. I was hoping to keep my mash temp even.

 

[doug293cz]

In BeerSmith you have to tell it what efficiency to assume in its calculations. It will tell you after the fact what efficiency you achieved if you give it the actual data for your brew session. As far as I know, BeerSmith does not adjust the efficiency used for recipe prediction as a function of grain bill weight.

Brew on

 

[pricelessbrewing]

I guess I was hoping that beer smith would help me estimate my efficiency.

Like doug said, beersmith is a good tool but it does not do estimates (despite how it says "Est. Mash Eff"), only calculates measured.

The "estimated" efficiency is really the user entered efficiency.

As far as I know, the only tools that do so are the stand alone batch sparge simulators, such as Braukaiser or dougs. If you want to see dougs work, it's built into my mash calculator (link in sig).

 

[doug293cz]

Like doug said, beersmith is a good tool but it does not do estimates (despite how it says "Est. Mash Eff"), only calculates measured.

The "estimated" efficiency is really the user entered efficiency.

As far as I know, the only tools that do so are the stand alone batch sparge simulators, such as Braukaiser or dougs. If you want to see dougs work, it's built into my mash calculator (link in sig).

The limitation of the simulators is that they only work for batch or no sparge. They can't handle fly sparging or the "hybrid" sparge described by the OP (if I understand the OP's process correctly.) If the process is other than the following, the simulators won't give accurate estimates:

1. Mash with known volume of strike water
2. Stir well, and then run off all wort
3. Add known amount of sparge water
4. Stir well and run off all wort

Steps 3 & 4 are optional, or may be repeated multiple times. Vorlaufing after stirring, prior to run off, is optional. Bag squeezing (if BIAB), as part of run off, is optional.

Brew on

 

[hoey222]

Ya. The more I stew over it, the more I think I need to revisit my sparge process. I'm trying to see if I can make no sparge work. But I'm not adjusting my recipe for the loss in efficiency. I think I just need to practice sparging.

Time to brew again.