Miserable efficiency, why?

[user 264271]

Hi friends,

I brew this bad boy today:

FYI I didn't do BIAB but Brew In A Basket (full volume 24L).

Pre-boil gravity was supposed to be 1056 SG and OG 1065 SG.
Actual readings were 1037 and 1050.

For a 15 L batch the efficiency was supposed to be 72% but according to BeerSmith it was 55%.

I did everything by the book, why so low extraction?
Grain crush?

I didn't stir after mashing in but recirculated like crazy.

WTF happened?

Thanks

 

[wilserbrewer]

Post a close up pic of your spent grain?

 

[BeeRRunBrewery]

You mention you didn’t stir in the grains when mashing in.... possibly a high amount of grain clumps/ balls?? If so, you can recirculate but if the water doesn’t contact the grains, it won’t extract sugar. I would brew it again, and mix the grains well to a thin “oatmeal”, then recirculate.

 

[RM-MN]

I did everything by the book, why so low extraction?
Grain crush?

I didn't stir after mashing in but recirculated like crazy.

WTF happened?

I don't stir after dough-in but I do stir well as I add the grains to make sure there are no dough balls. I also don't recirculate but my efficiency is much higher than yours. That suggests that the milling of the grain is the culprit as my grains are milled very fine. You can compensate a little for a poor crush by mashing longer but there are limits to that.

I'd suggest you buy a Corona style mill as they are cheap enough to get a payback in short order and give that a try, setting the mill as tight as you can and don't recirculate as that fine milling and recirculating don't work well together. I've come to expect brewhouse efficiency upwards of 85% with every batch.

 

[Waunabeer]

Most likely the grain crush. I tightened mine before my first BIAB batch and my efficiency was around 80%. I used a credit card to set the gap.

 

[balrog]

It really sounds like it's about the

 

[McKnuckle]

List of best practices to double check your procedure:

- Crush is as fine as possible for your lautering setup
- Stir well at dough-in to expose all grist to liquor
- Liquor is adjusted so that Mash pH is in proper range
- Rest temps are within range of alpha/beta amylase
- Rest duration is adequate for temp (lower temp = longer t)

 

[Hopalong]

Beer be sayin, tenfiddy be makin great beer.
Follow RMs suggestions, he's been making beer with the method for a long time and he's worked with a lot of recipes.
if Marris Otter is the malt of choice use Baird's 1823, it's low protein malt, less than 10%. The lower the protein the higher the sugar content. There's another maltster, I can't remember which one, that was producing 8% protein Marris, check Crisp. That would be the best Marris to use, but, corn and rice won't work with the 8% Marris. Alpha's pretty beat to death because the malt is over modified. I don't know what the diastatic power of Baird's 1823 is, it may be similar to the 8% malt.
Weyermann produces under modified, low protein malt. Under modified means the malt is rich in enzyme content. It is a little more expensive than high modified malt because it's richer in enzymes and sugar.
High modified malt modification is 42 to 47 Kolbach and the malt contains 12 to 16% protein. The exception being the low protein Marris Otter. The higher the Kolbach number the closer the seed comes to being a plant and the enzymes are beaten to death. Malt above 40 Kolbach is high modified malt.