Second BIAB: What did I do wrong?

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curtw

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So here's the deal: I brewed my second all-grain BIAB brew the other day, and I forgot to take a gravity reading before I pitched. Oh well, no worries, I just won't know what the ABV is of the final beer.

(I understand that taking a gravity reading of the wort+yeast is just going to give inaccurate results, so I didn't bother. Esp. since I used a 1-liter starter.)

So I figure I'd take a gravity reading after 24 hours, see what's happening. Well -- my hydrometer says 1.010 or so: about what I was hoping the FG would be...

My question is: Am I screwed; did I just have the worst efficiency possible? Or has the yeast fermentation caused some sort of differential in the wort/beer, such that all the sugars are at the bottom of my bucket (I took a sample from about the halfway point between top and bottom of my bucket).

Data:
- American Hefe recipe from https://www.homebrewtalk.com/f70/american-wheat-75279/
- Total grain bill: 5.5lb (2.6lb wheat malt; 2.0lb pale ale malt; 0.3lb Munich; 0.6lb flaked wheat)
- Scaled down to a 3.25-gal post-boil batch
- WPL320 yeast, 1-liter starter (should be fine, from yeastcalc.com)
- 5.0 gal water for mashing; 4.3 gal pre-boil; 3.25 gal post-boil
- Mash temp: starting temp 152F; it got down to ~148F after 25min, added some heat, back to 152F for the rest of the mash time
- 60 min mash
- No sparge; just let the grains drain for ~10min into BK.
- No idea about my mash water pH

Any advice or explanations welcome, thanks!
 
Umm everything looks good. My only explanation I can think of is was the grain even crushed?
 
Yes, the grain was crushed at the LHBS I bought the grain at. I'm no expert at grain milling, but it seemed crushed to me :).

Just one more piece of background: My first BIAB "all grain" brew was an English Bitter a few weeks ago. Since this was my first, I was prepared for terrible eff, and so bought some DME to supplement if the pre-boil (post-mash) gravity was really low.

Stupidly, I didn't account for the difference in pre- vs. post-boil volume and so the gravity reading was quite a bit lower than the expected OG. So I added 2lb of DME. Surprise, surprise: the post-boil OG was 20 points higher than expected -- i.e., if I'd added zero DME, I'd have been spot on. Same BIAB setup, same mash temp, same mash time, same wort volumes (different grains, of course).

(For this first brew, though, after I'd crushed the grains, I went to the nice LHBS dude and said, are these crushed enough? He said, hmm, let's run it through again. For my current (second) brew, I only crushed once -- it looked better to me than in the first set of grains a few weeks ago.)

So I assumed this time that my OG would be near what's expected (1.046), since I figured I'd be getting about the same efficiency. Which is why I'm just flummoxed...
 
how long after pitching the starter did you check gravity? And was the starter cold-crashed and decanted or pitched at high-krausen?

Maybe it's done. Very active fermentation can get you there in just few days. If you had no lag due to active starter, you could be very near FG already.

I say let it ride. How do the gravity samples taste?

EDIT:

OH, I see. 24 hrs. Hmmm... Not as hopeful. Well, do you need the fermenter? Ingredients are already used, so you'll still get a small beer if you let it go.

Maybe try mashout next time if you don't sparge?
 
Starter was created ~48 hr before pitching? Never saw krausen in the starter, but then I rarely do.

No, don't think it's done. What I got in the thief looked like barely colored water :-( . Didn't even make me want to taste it -- though next time I will for sure.

I haven't done a mashout yet. From reading I'd done, it seemed that mashout is mostly to insure sparging doesn't get stuck; since I'm doing no sparging, I figured it wouldn't do anything. Am I wrong about this?

Thanks!
 
I've read other BiaB-ers who claim mashout helps their efficiency when doing no-sparge. I dunk sparge in a second pot, so I haven't noticed a huge benefit. Although often, I'll fire the kettle a few minutes before I pull my bag :) just in case.

I think the idea is that warmer temps decrease the viscosity of the sugary wort so the sugars come off the grains easier.

I also squeeze my bag like it owes me money. Both when pulled from the main kettle after the mash and again after a 15 minute dunk sparge in the second pot. I want *all* of that sugary goodness!
 
I've read other BiaB-ers who claim mashout helps their efficiency when doing no-sparge. I dunk sparge in a second pot, so I haven't noticed a huge benefit. Although often, I'll fire the kettle a few minutes before I pull my bag :) just in case.

I think the idea is that warmer temps decrease the viscosity of the sugary wort so the sugars come off the grains easier.

I also squeeze my bag like it owes me money. Both when pulled from the main kettle after the mash and again after a 15 minute dunk sparge in the second pot. I want *all* of that sugary goodness!

This is indicative of my experience that doing a mashout will get you few more gravity points if not sparging. Doing a sparge, on the other hand, completely mitigates the need for a mashout.

As far as your problem, all indications sure point to your grains not being crushed. Though I suppose stranger things have happened, I don't think it's possible to get down to 1.010 in 24 hours and even crappy efficiency should've put you in the high 1.030s to start. Did you taste the wort at all during the mash? I take several temp readings and with each one give the wort a taste just to see how conversion is coming along. It starts out tasting like water, but by the time it's done, it's nice and sweet.

Another thought just occurred to me after taking another look at your recipe... almost half the grain bill is wheat malt. Wheat grains are a little smaller and a lot harder to crush than barley. What is the possibility that the wheat didn't get cracked due to too large a gap in the mill? That would have given you really crappy efficiency, so crappy that it might be feasible for the remaining fermentables to reach 1.010 after just 24 hours. When I did my first wheat beer, I milled my own grains at the LHBS using the default setting. When I got home I took a closer look and noticed that the wheat was not cracked. Decided right then and there to buy my own mill.
 
Did the wort going into the kettle and fermenter taste sweet? This is always a good sanity check. I sort of disagree with most here, in that I think that if you pitched a lot of yeast and fermented warm, a 1.040-1.050 beer could potentially be down to 1.010 in a day.
 
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