Been a member for several years but it’s my first time through the forums. I have a new problem that I am having a hard to figuring out the answer to.
I switched to all grain a couple years ago and started out with a 10 Gal Rubbermaid cooler for a mash tun with a Bazooka screen. I changed my process slightly as I learned more, but ultimately ended up right around 70% efficiency by mashing in at ~150 degrees F, mashing out at ~168, batch sparging at ~168 and draining to my kettle. Over time, my bazooka screen started to “break down” and I decided to replace it with a false bottom.
Now, my problem begins – I am averaging around 60% efficiency since the swap. I use the same process. I have used different grain sources and even purchased and have used my own grain bill on the last two batches. The 2nd most recent batch I ended up with 5 gallons of wort (as planned) and had a gravity of around 1.040 (expected ~1.050). This weekend I hit my gravity number (1.050) so I was prepared for better results, but ended up short on the wort and still ended with an efficiency of 62%.
I am close to ordering another bazooka screen and seeing if it corrects my results, but with either method I think my efficiency could be better overall. So, I am wondering if I am missing something fundamental since I would not have expected an efficiency drop with this type of equipment change.
Any help would be appreciated, and I can provide more details along the way if needed.
I did try that on my most recent batch, thinking I could now go with a finer crush than before. Although it was a Wit so half of the batch wasn’t milled. Maybe not the best recipe to judge those results?
Did you use a bunch of oats or something? It could possibly hurt efficiency if you had a stuck runoff and couldn’t collect all the sweet wort, although in cases like that you can try raking the surface of the mash or add rice hulls to help runoff.
I used flaked wheat and oats to make up 50% of the mash. Should have used rice hulls (I knew better) but I didn’t. Had an almost stuck sparge but got through it. Would have thought low efficiency was entirely do to the grain bill but this issue has happened over the last 4 brew days. Other days were 100% barley but had variables in the grain crush and source.
If you see this on every batch, it might be a combination of crush inconsistency, and a dead space issue. You’re batch sparging? After both the first and the second runnings, you need to tilt your cooler to get every last drop possible out of it. If you don’t, you’re leaving a lot of sugar in the mash tun.
+2 on the dead space likely increasing noticeably with the change to the false bottom. Extra lost sugars under the false bottom would account for the problem IMO.
Edit - As said, you obviously decrease the sugars lost if you can drain as many of them as possible (ie., tipping the cooler, etc.)
Thanks for the feedback everyone. Seems like a theme with deadspace. I have a couple recipes in mind in the next few weeks that are 100% barley and maybe the feedback here will help me dial it in.
Assuming you’re using a false bottom which was designed for round coolers and has a central sump pickup, I wouldn’t think you’d have more than a cup or two of liquid left, unless the hose connecting the sump to the valve becomes disconnected. I use a 10 gallon round cooler with a false bottom and BIAB, the only time I had more than a pint left in the dead space the hose had come loose so the siphon effect was broken. Titling the cooler will only leave you with more dead space loss if your false bottom has a central sump pickup.
Measured what was left in the dead space today, a little over half a cup. Not enough to make any difference in OG. If the siphon is disrupted due to too fast a runoff near the end [which did happen today] it’ll leave a bit under a pint.
That is what I am using. I tried to approximate the dead space before and had less than half a gallon. (I haven’t measured with just water). Given this, if dead space isn’t a concern, then what else could be the problem? Dialing in grain crush better?
In theory, the method of filtering wouldn’t make a difference beyond the amount of wort lost to deadspace. Any loses in efficiency should be coming from something else.
That is a good idea, you are probably right. I hope to brew this weekend and will focus on this. If I have the same results I post all of the above for feedback.
Are you sure that your hydrometer or refractometer isn’t out of whack?
You also might want to brew the one of the same recipes you did previously that had the higher efficiancy.
I have taken measurements with both of them back-to-back and they agree. If they are out of whack, they are out of whack together. And my next recipe will likely be one I have brewed before, so hopefully that will help.
I brewed again this past weekend. I did have a slightly higher Brewhouse Efficiency (65%) but still lower than I had been getting with a bazooka screen. Here is my recipe and steps, in hopes that someone might be able to point something out to get my efficiency a little higher:
HOME BREW RECIPE:
Title: Belgian Saison
Author: Tim
Brew Method: All Grain
Style Name: Saison
Boil Time: 60 min
Batch Size: 8 gallons (fermentor volume)
Boil Size: 9.5 gallons
Boil Gravity: 1.047
Efficiency: 70% (brew house)
STATS:
Original Gravity: 1.055
Final Gravity: 1.011
ABV (standard): 5.83%
IBU (tinseth): 25.71
SRM (morey): 3.14
FERMENTABLES:
14 lb - German - Pilsner (87.5%)
1 lb - German - Carapils (6.3%)
1 lb - Cane Sugar (6.3%) (late addition - 10 minutes remaining in boil)
HOPS:
3 oz - Saaz, Type: Pellet, AA: 3.5, Use: Boil for 60 min, IBU: 25.71
Generated by Brewer’s Friend - http://www.brewersfriend.com/
Date: 2016-09-15 01:40 UTC
Recipe Last Updated: 2016-09-10 16:38 UTC
---- BREW STEPS ----
Heated strike water of 4.75 gallons to mash in
Crushed grain (see photos)
Added 4.75 gallons of strike water to mash tun
added grains and stirred.
1.25 gts per lb
first rest 127 degrees F
added 2 gallons boiling to raise to 150.
added 2 gallons boiling to raise to mashout at 168.
Vorlaufed, then drained to kettle
batch sparged with 170 degree water (4 gallons)
Vorlaufed, then drained volume to kettle.
Boiled for one hour and ended up with 8.25 gallons in the fermentors (expected 8, so a little high).
