I brewed a brown ale yesterday that was targeted to hit 1.055 but finished as 1.044 with my recipe already adjusted to a 65% efficiency. I use a water pump to rinse my grains as a crude way of sparging but I realized that I've been doing this at around 150 degrees rather than 168, and only for a few minutes. Could this be the reason my efficiency is so low? I used 18.5lbs of 2 row and an additional 4.5 lbs of specialties with a final volume of 10.5 gallons. I realize that I can mash longer and get a finer gain mill,but I wondered if my sparging method is the underlying culprit. PLEASE HELP!
Lower than 60% efficiency?
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I have only one biab done and my efficiency was low also. It was because of a faulty thermometer. Mash temp was low and sparge temp was low 20 or so degrees. I squeezed the hell out if the bag. Im glad i did, i managed 66% efficiency
I worried about that too but I used 2 thermometers and got nearly the same reading and both were well within a range of 148 and 154. I should probably upgrade to a weldless on the side but I like being able to measure the temp difference in the grains and outside of them. Could you imagine that my sparging method would cause the "inefficiency"?
Temp of sparge doesn't really matter. We'll need more info to provide some suggestions as to the culprit.
Did you take a preboil reading? What temp did you take the reading at? Hydrometer or refractometer? Describe the crush. Mash time? What did you use for sparge water?
How did you sparge? You say you used a pump, but those are typically used for full volume recirculation set ups, not sparging.
Any details you can provide would help.
Did you take a preboil reading? What temp did you take the reading at? Hydrometer or refractometer? Describe the crush. Mash time? What did you use for sparge water?
How did you sparge? You say you used a pump, but those are typically used for full volume recirculation set ups, not sparging.
Any details you can provide would help.
My preboil gravity was 1.058 but I didn't do a full volume mash, so I added the necessary water and took the hit on gravity to get my 10.5 gal. I measured the gravity with a hydrometer but I accounted for the temp when I took it; according to the Brewing Great Beers book.
I don't have a metric for the crush, I just used what the brew store had (one time through).
I did a one hour mash and used the wort as my "sparge". I was under the impression that using the pump to recirculate the wort over the raised bag of grains would rinse the grain sufficiently.
I don't have a metric for the crush, I just used what the brew store had (one time through).
I did a one hour mash and used the wort as my "sparge". I was under the impression that using the pump to recirculate the wort over the raised bag of grains would rinse the grain sufficiently.
No. Recirculating the wort over the grain is not the same as sparging. The concentration of sugar in the wort is essentially the same as the concentration of sugars remaining in the grain. You need to use fresh water to get more sugar out of the grain, which is what a real sparge is.
Brew on
Gnomebrewer
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Mash efficiency, or total efficiency?
There's a big difference. Total efficiency includes loss to true etc.
There's the red flag. The brew store doesn't have any reason to get you a great crush. Poor crushes never get you a bunch of mad customers that all had stuck sparges and it gives them a reason to sell more grain. If you want great efficiency, get your own mill. That's the only way you can control the quality of the milling. A cheap Corona knock-off works well for BIAB, getting me about 80% efficiency with no sparge or 85% with a small sparge. If you get one for BIAB, set it as fine as you can.
brewbama
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You beat me to it. Crush was probably too course. If you don't hit OG I believe low conversion is the cause. Crush is probably the No 1 reason for low conversion.
If you hit OG within a point or three plus or minus but still got low brew house efficiency, it's probably because there's dead space, loss to trub, etc in the brew house.
What does recirculating the wort do!? Haha I was misled somewhere along the line. The efficiency I was talking about was my mash efficiency.
So if I change just my crush, what kind of change in mash efficiency can I expect, roughly?
So if I change just my crush, what kind of change in mash efficiency can I expect, roughly?
Correct, for the most part. Recirculation during mash is similar to stirring constantly, so will help reduce temperature gradients in the mash if you have a good flow pattern. With a coarse crush, it may help somewhat to mitigate the diffusion limitation on sugar extraction. But, unless the recirc loop is well insulated, recirculation will cause more temperature loss during the mash. So, you need to be able to make up for the heat loss with the ability to apply more heat.
Brew on
As was mentioned, recirculating the wort isn't 'sparging', so a no sparge brew is what you did.
The big hit came from topping up with water. Remember that there is 0 sugar from the grain in water. Ideally, you'd do either a full volume match (lots of BIABers do) or a mash in the lower volume an a sparge. A sparge is using fresh water to 'rinse' the grain through the process of diffusion so that's why it's important to use water and not wort. topping up with water will cause a huge hit in your efficiency numbers.
btbnl
Well-Known Member
When did you add the extra water? I'd expect it to be added to the wort after pulling the bag, but is sounds like it might have been added post-boil to get to exactly 10.5 gallons. If the latter, then it may be that it just hadn't mixed fully and you got a bad reading.
If we knew the volume of the pre-boil 1.058 wort (V) then using the conservation of sugar we could also calculate the gravity of the post-boil 10.5 gallons (G) as:
G = 1 + 0.058 x V / 10.5
Conversely, if your post-boil/10.5 gallon wort's gravity really was 1.044 then your pre-boil/1.058 gravity wort's volume must have been about 8 gallons. Correct?
If we knew the volume of the pre-boil 1.058 wort (V) then using the conservation of sugar we could also calculate the gravity of the post-boil 10.5 gallons (G) as:
G = 1 + 0.058 x V / 10.5
Conversely, if your post-boil/10.5 gallon wort's gravity really was 1.044 then your pre-boil/1.058 gravity wort's volume must have been about 8 gallons. Correct?
I didn't measure the volume after the mash but that sounds about right because I added around 3 to 3.5 gallons before boiling.
Since this was only my third batch I was more concerned with hitting my target final volume rather than gravity; just to see what my system was like.
I'm brewing an imperial IPA this weekend, let's hope the crush solves the problem! And I won't be sparging with wort! Haha
Since this was only my third batch I was more concerned with hitting my target final volume rather than gravity; just to see what my system was like.
I'm brewing an imperial IPA this weekend, let's hope the crush solves the problem! And I won't be sparging with wort! Haha
Adjusting for temperature with a hydrometer gets less accurate as the sample temp goes up. Anything above 100 is basically worthless, and ideally you wouldn't measure above 80.
Also, pre-boil gravity is the gravity with all of your water added, so 1.058 wasn't your pre-boil gravity, it was your pre-top-off gravity. Measuring pre-boil is of limited use, but if you do it in the future, do it when you're at full pre-boil volume.
Also, don't top-off with water after your mash. If you need extra water, sparge it over or through your grain bag to get the extra sugars out. I do a dunk or a pourover sparge of my grain bag to get up to pre-boil volume (based on numbers calculated before I start my mash), and that gives me a notable efficiency boost. You can even do a cold water pourover/dunk sparge to rinse the grains and cool them down so squeezing the bag is easier. If anything, that increases my efficiency because I'm able to squeeze more liquid out of the grain bag. The downside is that adding cold sparge water means it takes longer to reach a boil in the kettle.
