Used a Mash Tun Filter: Overshot OG

[SouthPhillyBr3w3r]

Hey all.

I just brewed a Belgian-style witbier yesterday, and it was my first brew where I used a Brew Bag as a Mash Tun Filter. I guess this is BIAB? I used my normal 10-gallon igloo cooler with false bottom, but lined it with a Brew Bag MLT filter. Ordinarily I fly sparge, but this time I batch sparged, then hung the bag over the MLT to drain out excess sweet wort.

When I developed the recipe on my brewing software, I entered in 70% brewhouse efficiency and it said my Post-Boil OG would be 1.050. Using the above technique, my Pre-boil OG was 1.052 and my Post-Boil OG was 1.062. Other than having way overshot my OG, I am surprised because my software says I would have had to hit 92% efficiency to get this gravity in a 5.5 gal batch from my grain bill. 92% efficiency is unheard of. I did double crush my grains with my mill set finer than usual, so maybe that led to increased extract efficiency, but 92% seems impossible. Any thoughts on this?

p.s. I will probably dilute the beer with a little distilled water post-fermentation to bring the ABV down to the acceptable range for a Belgian Wit.

 

[RM-MN]

Oh yes you did BIAB although not in the traditional sense since you used a cooler instead of just mashing in the boil pot. Hanging the bag to let it drip helped increase your efficiency as you collected more sweet wort since the hanging bag does squeeze the grain some. The double crush also helps a lot. I wouldn't be sure of the 92% because when getting that high efficiency numbers a slight error in measuring the quantity of wort can skew the results but you definitely got high efficiency. Congrats. Now you have started down the rabbit hole that may lead you to go completely BIAB or maybe not. Doing the mash in the cooler helps keep the mash temperature stable and only requires cleaning the cooler which should not be a big job.

 

[SouthPhillyBr3w3r]

Yeah. Cleanup was definitely a lot easier. I guess I can also cut down on the size of my grain bill from here on out. I actually had a gallon of wort left over (more than I wanted to put in the kettle) so I'm using it to make canned starter wort. What are the advantages of doing full-blown BIAB?

I guess this should be moved to the BIAB forum?

 

[RM-MN]

Yeah. Cleanup was definitely a lot easier. I guess I can also cut down on the size of my grain bill from here on out. I actually had a gallon of wort left over (more than I wanted to put in the kettle) so I'm using it to make canned starter wort. What are the advantages of doing full-blown BIAB?

I guess this should be moved to the BIAB forum?

The only real advantage to full blown BIAB is that you don't have to clean the cooler. Instead, in order to get the efficiency you got you need some way to sparge and you don't have to buy a cooler. Since you already have the cooler, there is no buy for you.

Canning the wort is a fine idea but be sure to pressure can it as doing just a water bath can lead to botulin poisoning. It takes the higher temperature of the pressure canner to kill botulin spores.

The chance of botulin poisoning is very low but the results can be death.

I don't see a reason to move this thread. If anything it may serve as inspiration for someone else to try what you did.

 

[leonardoreges]

I don't see why should you change anything in your process.
You've got an efficiency dreamed by every home brewer without many effort.
Keep the way it is.

 

[SouthPhillyBr3w3r]

Thanks for the replies. One thing I love about home brewing is that a total accident can change the way you brew, and beer... Beer is a plus. Also, RN-MN, I do use a pressure cooker to can my wort. I usually run it for about 20 minutes and let it cool naturally in the sealed pot until it hits room temp, then ice bath to make sure it's totally vac-sealed.

 

[SFC Rudy]

I started using a brew bag in my cooler mash tun, and I've gone lazy and started to use the no-sparge approach, or batch sparge with a large grain bill. Life is so much easier now.