Consistant low effeciency. What can I do?

[Ender335]

I've brewed close to 10 5-gallon all-grain batches so far and I always get a low efficiency. I seem to be off by ~16 points or so and so, and to correct the problem, I usually have to add about 2 pounds of DME.

I know many people suggest crushing my own grain. I love the idea, but I'm not in a position do that yet. All of my kits I bought are pre-crushed and most of my kits have been from NB, with one from Midwest Supplies and one from brewmasters warehouse. I'm not an expect in the grain crush but the crush looks good.

When I empty the grain from my MLT, I notice some wort in there (probably a lot more than there should be). I think this is most likely the culprit for my poor efficiency. The cooler I'm using as a MLT is rectangular, being more wide than deep. The drain is at the bottom of the front of the cooler connected to a SS braid as a filter. The braid is longer than the cooler is deep and I notice that sometimes the filter gets stuck in the grain i.e. off the cooler floor.

Could that be causing my poor efficiency? I'd really appreciate any help. 2 pounds of DME is expensive every batch.

 

[prosper]

need more information about your process.

Could be as simple as a measurement error - a scale or hydrometer that's out, or volumetric measurement errors.

I'd argue that if it's *consistent*, then it's not really a problem. Actually, I'd personally much rather have an efficiency that I can count on batch-to-batch, then one that's high, but fluctuates a lot. Just calculate your recipes with your measured efficiency, and go from there. A few pounds more base malt is cheap.

Without knowing more about your process, recipes, etc - I can tell you that the mash tun probably isn't the problem. I have used an identical setup in the past, and hit 85%-90% efficiency with it consistently. (I've since made alterations to my process and equipment and lowered my efficiencies by about 10%).

 

[Ender335]

One thing is the kits are designed for 5-gallons and I use the beersmith's instructions for 5.25 gallons. I heat my mash water and throw it in my cooler for 5-10 to preheat it. I pour in my grain and mix it all in for a few minutes until I'm sure it's thoroughly mixed. I check the temperature and correct it if necessary.

After an hour, I vorlouf, lauter, and do two rounds of batch sparging until I get to my recommended pre-boil volume. I stir the wort, take a sample and cool it until its around 70 degrees. I record the pre-boil gravity and its usually off by 16 points. I take another sample after I cool the wort and its usually right where it should be.

 

[SwampassJ]

Try stuffing some stainless steel nuts into the braid to weigh it down. If you've been using kits from 3 different sources with the same efficiency then I doubt it's the store. Brewmasters for my last brew day hit over 80% which is good for more alcohol, bad that I calculated at 70% for my beers.

How much liquid is being left behind? I switched to my current cooler which holds heat less well than the last but the spigot is recessed into a groove in the bottom so I don't lose half a gallon in the cooler. I also prop the opposite end up on a folded beach towel to better aid the drainage.

Check your hydrometer in some 60 degree water, it should be 1.000 (screw the distilled water at this point). Check the thermometer temperature. In a boiling pot it should read 212 give or take your altitude. Are you mashing with reverse osmosis water or distilled? Are you using 5.2 ph stabilizer?

 

[Ender335]

I would esitmate the water at around a quart. I do tilt my cooler help drain more liquid. I will defiantly have to test my hydrometer. I'm mashing with tap water and I do not use 5.2 ph stabalizer.

 

[tunoffun]

One thing is the kits are designed for 5-gallons and I use the beersmith's instructions for 5.25 gallons. I heat my mash water and throw it in my cooler for 5-10 to preheat it. I pour in my grain and mix it all in for a few minutes until I'm sure it's thoroughly mixed. I check the temperature and correct it if necessary.

After an hour, I vorlouf, lauter, and do two rounds of batch sparging until I get to my recommended pre-boil volume. I stir the wort, take a sample and cool it until its around 70 degrees. I record the pre-boil gravity and its usually off by 16 points. I take another sample after I cool the wort and its usually right where it should be.

Maybe I'm reading this wrong, but I see a host of potential problems.

First off - the thing about making 5.25 gallons from a 5-gallon kit. If you're using beersmith to calculate the estimated OG from the actual grain bill, then you should be fine. But if you're assuming the OG from the kit, but producing more wort than intended... it's obviously going to be off.

Second - you say you preheat your tun. But are you re-circulating the water back to your pot to heat it back up to temp after it's transferred heat to the tun? In other words.... when you add your grain, is both the water actually at your intended strike temp at that moment?

Also - I believe it's better to add water to the grain rather than the other way around to prevent doughballs from forming... lumps of grain that aren't wetted in the center. Are you stirring thoroughly (and I mean THOROUGH) to completely break up any doughballs that may form? If you're not, that could be a big issue.

Finally - I'm not sure what you mean by your last sentence (taking another sample after the wort has cooled & it's right where it's supposed to be)? Do you mean you start out w/ a preboil volume that's lower OG than expected, but end up w/ a post-boil volume that's at the SG you expect from the recipe? In that case, you're either off on your pre-boil volume, or you're off on your evaporation (which would mean you're off on your post-boil volume).

Beersmith allows you to enter values for your mash tun dead space, etc. Have you calculated how much is actually trapped by your tun and plugged in those values? And yes... if your screen is moving up, it's going to change how much wort is left in the tun, which will affect this value and likewise your efficiency.

 

[mojotele]

I'm beginning to feel like a broken record here, but you need to analyze things more before acting.

Your brewhouse efficiency is actually made up of two separate figures: conversion efficiency and lautering efficiency. The earlier is a measurement of how much of the grain's potential was realized. The latter is a measurement of how much of the sugars you actually got out of the tun.

Most people assume conversion problems when you get low efficiency. And, indeed, that's usually the case. But it could be lautering problems too. Anyway, measuring these things is really simple. Assuming you're batch sparging, get Kai's spreadsheet here. Next brew day, input the amount of grain you're using, the grain's potential, and some other figures like how much water you used total, how much strike water was used, etc. You'll have to make some extra measurements like the gravity of your first runnings, temperature of first runnings, temperature of the total volume in the kettle after each running, etc. None of it is particularly hard, though.

In the end, you'll have your conversion and lautering efficiency and a good idea as to where you need to improve. Kai's wiki has potential problem areas for each efficiency that you can examine. That page also describes efficiency much more thoroughly than I just did and gives you some info as to why you're doing everything you're doing to determine the numbers.

 

[Ender335]

Thanks to everyone for their help. I've gotten a lot of great suggestions that I will do for my next batch and I'll defiantly look into seeing if its my lautering efficiency that's the problem. You guys are amazing!