BIAB Efficiency

Mashing
1

I just finished my first BIAB and was trying to figure out efficiency. I was looking to make a Hoegaarden type beer. My grain bill included
3 lbs of Best Malz Pilsen Malt
3 lbs of Rahr White Wheat Malt
1 lb of Rice Hulls
1/2 lb of Rolled Oats

I heated 10 quarts of water to 130 degrees, held between 120 and 130 for 30 minutes. Added 10 quarts of 170 degree water and held between 150 and 160 for 60 minutes. Sparged with a few quarts and let lauter for 5 minutes or so. (Not exact on the water quantities)

At boil, I added 3/4 of a lb of Amber DME.

I then added 1 ounce of Halertau for 60 minutes
1/2 ounce of corriander and 3/8 ounce of orange peel at 45 minutes
1/2 ounce of corriander and 3/8 ounce of orange peel at 1 minute

My final brix after cooling to 68 degrees was 14.2, OG of 1.059.
I was kind of winging the recipe based on multiple recipes I found online, was hoping for a yield of 4 gallons, but I wound up with a yield of 4.5 gallons

After the fact, I input this recipe on TastyBrew.com recipe calculator and it predicted a starting OG of 1.057

How do I determine my efficiency? I was pleasantly surprised how easy it was. The wort smelled and tasted fantastic, can’t wait to get this into a keg.

Should I expect a better efficiency with a mash tun or is it mostly used for larger batches. I don’t think I could fit much more in a brewpot. I was using a 24 quart pot.

Thanks for any help.

2

How much wort was there at the beginning of the boil?

3

I do not have gallon mark in my kettle, but I would guess around 5 gallons. I keep a lid just cracked on my boil, it leans so that most of the evaporation hits to lid, condenses and drops back into the boil.

4

I put the numbers in the calculator on Brewers Friend. I subtracted .008 since that is what the DME added. So that put you at .051 that’s 89.7% efficiency if you started the boil with 4.5 gal.and didn’t loose much during the boil, if you started the boil with 5 gal you efficiency goes to 100%. I’v been getting 85% with BIAB my tun I get 80%. I have to adjust accordingly. you really need to know your exact volumes though.

5

Thanks,Brew Cat I will be carful to measure water volume accurately in future BIAB’s. A have an observation that I would like an opinion on from the spent grains. When I looked at the grain after lautering, I was surprised how well it drained (I did not squeeze). I feel like the rice hulls contributed a great deal to how much sugar was extracted from the grains, even if they did not contribute much themselves. They almost had the texture if chipped wood. Can you use chipped oak or pecan in your grain bill.

6

Looks like Brew Cat was right on. My own software says your efficiency was about 90%, which is not impossible but very unlikely for a beginner. Measurements of weights of your grains and all your volume measurements need to be exactly accurate to calculate your exact efficiency.

7

Letting the condensation drip back into the boil is not advised.

From John Palmers How to brew:
Once you achieve a boil, only partially cover the pot, if at all. Why? Because in wort there are sulfur compounds that evolve and boil off. If they aren’t removed during the boil, the can form dimethyl sulfide which contributes a cooked cabbage or corn-like flavor to the beer. If the cover is left on the pot, or left on such that the condensate from the lid can drip back in, then these flavors will have a much greater chance of showing up in the finished beer.

It maybe ok to let the condensation drip back in, but I would just adjust the water content to let it boil off.

8

I have marks on the outside of my pot so I measure to the liquid with a tape measure and check it on the outside. I put the marks on with permanent marker

9

Thanks for all of the advice. I will make sure I keep the lid off and account for more evaporation.
I mark my glass carboys for 4, 4.5, 5 and 5.5 gallons with a marker. Did not think about marking the outside of my kettle. I have been reading posts on the site for over a year, did not ask alot, just read. Since I just made my first BIAB, I read and have more and more questions. Lots of people with great knowledge willing to share. I have to read all of Palmers book.

I started this post with a question about efficiency. Still struggling to understand. For a theoretical discussion, if you start with 7 1/2 pounds of various grains, there is a maximum amount of sugars that can be extracted from the grains. From what I have read, step mashing extracts the most sugars. I only used 2 steps and lautering, but I understand you can do more. Irregardless of how much water I start with, add in the steps, and lauter with, after boiling the wort, you end up with a certain amount of wort with a measured gravity. Doesn’t the final measured gravity determine your efficiency. What percent of sugars did you extract from your grains?

10

You’re correct. There is a maximum amount of sugars that can be extracted from any grain. The exact maximum varies depending on the particular malt being used. Given one pound of malt fully extracted in one gallon of wort, most base malts will give you a maximum gravity of 1.035 to 1.039, or about 1.037 on the average. This does also depend on the variety of malt, where it is grown, how ripe it was at the picking, differences from season to season, etc. But for a good ballpark, you can usually use about 1.037 for a pound of base malt in a gallon of beer.

The really difficult part comes in with all the specialty malts, where the maximums for those range all over the place from 1.030 to 1.040 or anywhere in between.

So, what does all this mean? You don’t usually just use one single pound of grain in one gallon of wort, so how practical is any of this information? Well, in many ways, it’s not. But, it CAN be used in homebrewing software to help you figure out what percentage of the maximum you have reached. There are ways to calculate all this stuff by hand, but it’s a mess. It’s usually best to just pick your favorite software, pump everything in, and then figure out your efficiency from there.

Determination of your average efficiency is useful for predictability. When I want to make a 1.045 ale, I don’t necessarily want to end up with 1.060 or 1.040 or something else… personally, I’d be most interested in hitting 1.045 on the nose. With experience, I might learn that my typical efficiency is 75% or 85% or even 90%. Then I can use this information in my software to help me pinpoint exactly how many pounds of grain I need to achieve my goals, whatever they are.

That’s pretty much how it all works. But you really do need to be consistent in how hard you crush your grains, and how accurate you measure all your volumes, before you can truly come to an understanding of how efficient your own process is on the average.

I could go even deeper and tell you that efficiency tends to improve as you go lower in anticipated gravity, and gets worse as your gravity goal goes higher, but this is slightly more advanced… (seriously, only slightly!).

11

Picture is getting clearer. All grain brews are like science experiments. So many variables, keep a many as you can steady and predictable, keep good records, tinker with one aspect at a time and note the results. Make small improvements until you have the perfect recipe. I should be busy at this for the next twenty yers or so.

12

I have marks on the outside of my pot so I measure to the liquid with a tape measure and check it on the outside. I put the marks on with permanent marker[/quote]
I have a steel ruler, originally made for drafting. I put little notches at the gallon marks, and use it as a dipstick.

I put the notches on the centimeter side because I don’t use metric. Murica!