First decoction and horrible efficiency. Help!

[jpoder]

So I brewed a batch of 'The Pious' traditional recipe over the weekend, and ended up with a stinking 55% efficiency! Worst I've ever had by a long shot, but this was my first decoction, so I'll chalk it up to rookie mistakes. I'm hoping someone can help point to my worst offenses.

Here is how it was supposed to go:

2 min Protein Rest: Add 21.79 qt of water at 141.1 F
35 min - Hold mash at 132.0 F for 35 min
2 min Saccharification: Decoct 6.52 qt of mash and boil it
20 min - Hold mash at 151.0 F for 20 min
2 min Saccharification: Decoct 3.60 qt of mash and boil it
20 min - Hold mash at 159.0 F for 20 min
-- Sparge with 4.92 gal of 168.0 F water.
-- Add water to achieve boil volume of 7.94 gal

Protein rest went fine. pulled the decoction for the Sacc. rest took 20 minutes to get it to boil, added it back to the main mash, but overshot (160!)

threw in a couple of ice cubes, and stirred the heck out of it to bring it down to 151. (did I denature most/all of the enzymes at this point?!). not sure how I was so far off. Beersmith has never steered me so wrong in the past!

second decoction went fine (took 15 minutes to get decoct to boil), and hit the correct temp when I stirred back in (I pulled a lot thinner of a decoction this time). sparge and boil proceeded as normal.

I did not take a pre-boil gravity. It wasn't until I was ready to pitch did I take a reading and was at 1.078 instead of 1.095

Where would you say I screwed up? Should I have held the sacc rests longer? by overshooting the first sacc rest did I hose myself?

beer seems to be fermenting away nicely now, and should make a tasty beer regardless, I'd just like to figure out how to improve my process.

 

[Zamial]

Not an expert but there are a few things I see...

but overshot (160!)

This is a serious issue. In my experience it is better to under shoot than over. Once over the enzymes that convert the sugars are destroyed. It is better to come up from the low end to the top of the temp range. I suspect that with that temp spike you had poor conversion and thus poor efficiency.

I do think the protein rest was ok. The times below reflect the high end of the temp scale, the lower the temps the longer I mash...Normally on a pilsner base grain mash I do this:

Protein rest for 30 minutes at 122-130 <- only with pils malts or malts that require this.

Raise temp by adding in more water to mash temp 148-152 for 30 minutes, drain.

Raise temp for second running's 152-158 for 30 minutes, drain

Raise temp to mash out temps 168 for 30 minutes.

There is a chart in "The complete joys of home brewing" that has it all figured out already with water temps + volume based on grain volume.

Well that is my 0.02 anyways...BTW I batch sparge...hope this helps.