Efficiency Problems

[bmack]

Hello Everyone, I was hoping I could get some advice on how to improve my all grain efficiency. I've searched the forums, read books, and watched video tutorials to try to help improve my process, but I keep having a problem with low efficiency. I brew predominately small batches (1 gallon), and my efficiency has been between 45-55% each time over the last 8 batches. I've been calculating my efficiency using beersmith based on an original gravity reading from my 1 gallon jug just before pitching.

Here's a breakdown of my current process, I'm just curious if maybe I am doing something wrong that might stick out to a more experienced brewer.

• I use a 2 gallon stock pot from wal-mart to heat my strike water to 180 degrees (1.5 qts per lb of grain)
  
• I add the water to a 2 gallon rubbermaid cooler mash tun and let the temperature drop to about 170
  
• Add the grain about 1 cup at a time, stirring out any doughballs
  
• The temperature usually drops to about 155 by this point, and I seal the cooler for 60 minutes (my mash tun drops about 3 degrees during the hour)
  
• After 60 minutes I vorlof until the wort clears a bit, then slowly sparge using 170 degree strike water (To sparge I pour the water through a pie pan with holes poked in the bottom, laying on top of the tun) I usually collect about 1.75 gallons of wort, and proceed to the boil.
  
• I lose about a half gallon to evaporation during the boil, leaving me with about 1 gallon of siphoned wort less trub left in the pot.

Based on what I've described, is there anything apparent that I'm not doing correctly that could be causing my low efficiency? Also, please let me know if there is any information I may have left out that could help with a diagnosis. Thanks in advance.

 

[Pie_Man]

The crush of your grain, the crush of your grain, and the crush of your grain are probably the three most important aspects to improve mash efficieny. Mash efficiency is calculated using your pre-boil wort, not post boil wort prior just prior to pitching. Having a reasonably accurate pre-boil volume is also important. What I do is pull a sample from my pre boil volume and cool it while I am bring the wort to a boil. I take my measurement at about 60F then return the sample to the BK. Unless you are referring to brewhouse efficiency...but either way, improving your mash efficiency will improve the brewhouse eff.

Additionally, I think your dough in temp is a little high. When I do five gallon batchs, I am usually somewhere in the 160s. I'd add the grains to the water at a faster rate and stir vigourously until you reach your mash temp. In my experience, you do not have to be overly concerned about dough balls, stirring will break them up anyway.

You may also want to try batch sparging for a better rinse of your grain bed. Drain the wort from the mash, add the full volume of sparge water to reach your pre boil volume, stir like crazy, let the grain bed settle for about 10 minutes, vorlauf, then drain to your BK.

Hope this helps.

 

[brewkinger]

Yeah, like mentioned above, it sounds like you are fly sparging.

When your vorlauf til it runs clear, you are dumping that unclear stuff back into the mash correct ??
Once it runs clear, you drain the tun and this is called first runnings.
Figure out how much volume you have and dump your sparge water amount in and stir like a madman.
The grains will not absorb any of this sparge, so water in equals water out.
Get your pre boil volume and then boil.

As far as increasing efficiency, there are two main ways:
The crush of your grain and the crush of your grain. If your LHBS is crushing for you then you may want to ask Politely for a double crush or possibly invest in your own mill.

 

[brick]

It would be helpful if you would check the gravity of your final runnings (taken directly from the mash tun right before you quit sparging) and report back. That tells us if it's an extraction problem (sugar not converting or not making it outside of the grains) or a sparging problem (sugar not making it out of the mash tun).

 

[Calder]

Your 50% efficiency is the overall efficiency of your process, not your mash efficiency. Measure pre-boil gravity to get mash efficiency. You say you leave about a quarter gallon in the pot; that would increase your mash efficiency by 25% over what you have measured.

Are you truly brewing 1 gallon? If it is higher, again your efficiency would be higher.

Grain crush is the first thing to look to to improve extraction.

170 F seems high, especially if you are using 1.5 qts/lb.

 

[bmack]

Wow, thanks everyone. I'm taking from this that I should try dropping my temps a bit, batch sparging may help, and obviously the crush of my grain may be an issue as well (I have been getting all my grain from the same LHBS). I will also research the differences between mash efficiency and brewhouse efficiency because I may have those confused a bit. This has been a big help, thank you.