Extraction efficiency

[nelstrodomus]

Where do most brewers lose efficiency in their systems?

I've been batch sparging and getting really low efficiencies on my setup (half barrel insulated keg with SS braided hose setup).

I can use any advice because I'm in the 55-60% efficiency and simply not able to get the OGs that I want.

[Mill Rat]

First concern is your grain milling. You should mill your grain as fine as you can without getting stuck sparges. if you get your grain pre-milled, you may need to try an alternate supplier. The second place where you can lose efficiency is by leaving sugars in the lauter tun. When I dive into a new venture, I always try to find out what the pros use. They have a wealth of experience and their selections can save you a lot of time. Pro setups use a false bottom. End of story. Even if you aren't going to use a FB, you need to approximate the even draw that they provide. I have yet to see a bazooka screen system that does that well. Pipe manifolds can get a lot closer.

There are other places to look to improve you efficiency, and not having tried batch sparging I can't comment on the relative merits of batch versus the fly sparging I do, but your grind and lauter tun are the first places I'd look.

[dparsons]

Mill Rat is right that the milling is the 1st place to look. Leaving the mash sit longer will also help. A third step is to do a mashout - add more hot water to bring the mash up to 168*F. More sugar will stay in suspension at higher temperatures and will flow more easily as well.

[Mill Rat]

Good point, dparsons. When doing a mashout, though, make sure you're happy with how well converted the mash is. The classic reason for doing a mashout is to inactivate the amylase enzymes and halt the conversion or the more complex sugars to more fermentables. Since homebrewers are more vulnerable to underconversion than overconversion (heavy-bodied versus thin-bodied), I don't bother too often with a mashout unless I am brewing something with an OG over about 1.075. I mashout the higher gravity worts after a generously long saccarification mash in order to increase sugar solubility and reduce the amount of runnings that have to boiled down. If I lauter at saccaraification temps (~150 F, 65 C) i get first runnings at about 17 Brix. At mashout temps (~170 F, 71 C), I see about 22 Brix.

[Richter]

With my alkaline water, using acidulated malt or 5.2 stabilizer seems to help efficiency too.

[branlovesbeer]

Okay... Dumb question.

But how do you measure your efficiency? I always hear people saying 60%, 75 %, etc. How exactly do you calulate that unless you have really expensive chemistry tools?

[darylM]

Okay... Dumb question.

But how do you measure your efficiency? I always hear people saying 60%, 75 %, etc. How exactly do you calulate that unless you have really expensive chemistry tools?

The cool part is that you don't need expensive chemistry tools. If you go to www.byo.com, there are a few pages giving lab sg yeilds in the per pound per gallon. With that information you can figure out the number of gravity units that a 100% extraction would have. Then take a hydrommeter reading and mulitply by the number of gallons and you will have your extraction gravity units. Then its a matter of dividing your extraction by lab extraction and mutliply by 100.

[nelstrodomus]

If you have brewing software you can adjust the efficiency based on your grain bill until you hit your SG, that's what I do.

i.e., If it's set for 70% but you hit a higher SG than expected, you can adjust it up until you've hit your SG and that will give you your efficiency percentage.

[JayShaw91]

Yes on the milling, but I have to step in and be contrarian here on the false bottom's are better thing. I use a Bazooka screen in a square marine cooler and I regularly get 80% efficiency. That said, this was due to getting a mill and grinding myself. The HBS was apparently undermilling my malt. Prior to getting the mill I hit 70% once.

FYI, I have a JSP Maltmill which has an offset of .045".

[Mad Scientist]

Yes on the milling, but I have to step in and be contrarian here on the false bottom's are better thing. I use a Bazooka screen in a square marine cooler and I regularly get 80% efficiency. That said, this was due to getting a mill and grinding myself. The HBS was apparently undermilling my malt. Prior to getting the mill I hit 70% once.

FYI, I have a JSP Maltmill which has an offset of .045".

Yup, I had to mill my grain to corret an extraction problem. my typical is around 75%. I use a barley crusher.

[dparsons]

Okay...

But how do you measure your efficiency? I always hear people saying 60%, 75 %, etc. How exactly do you calulate that unless you have really expensive chemistry tools?

Efficiency is measured by measuring your resultant gravity and comparing it to the maximum possible gravity. The maximum possible is determined from the grain additions if 100% converted. If you look at the numbers in brewing software, grains are given a potential gravity number. This could be 1.035 for instance. What this means is that if all the starch of 1 lb. of grain ends up converted to sugar in 1 gallon of water, the gravity will be 1.035. Thus a grain bill can be added up and divided by the number of gallons for a batch potential. If you used 8 lb. of the above grain in a 5 gallon batch, you get
potential = 1.035 * 8 / 5 = 1.056
If you get a final gravity of 1.040 then your efficiency is
(1.040 - 1) / (1.056 - 1) = .714 = 71.4%
Subtracting the 1 in the final equation removes the water from the efficiency calculation.