Help with poor efficiency on Anvil 6.5

[Obi]

Hey Everyone,

I've been brewing off and on for several years, but there is a difference between cumulative years of experience and repeating the same experience for several years... so for the sake of this post let's assume I have a very basic level of brewing knowledge. I can put grain in one side and get a tasty brew on the other end, but most of the magic in between I know from a 30,000 ft view.

I picked up an Anvil Foundry 6.5 a little while ago and only have 3 brews on it so far. The problem I have been having has been a low and inconsistent brewhouse efficiency between the "expected" and "measured" OG that I'm getting into the fermenter. If it was either low OR inconsistent it would be easier to pinpoint what I'm doing wrong, but so far it has been both.

My first batch I mashed at 155, no mash out step, and sparged (although probably too quickly). The other two brews I did a mash out at 168 for 10 minutes with the grain still submerged, then raised the basket and let it drain while heating the wort to boiling.

So far I have had a 60%, 55%, and 50% efficiency on the system, respective to the methods above. While it still comes out as a tasty brew on the other end, it does make it frustrating since I am unable to design a beer around a moving target.

On this kind of system, what would be the most likely culprit for low efficiency that I should try fixing first? Any experience on the system or words of wisdom?

Thanks in advance, cheers!

 

[Oginme]

Are you recirculating during the mash?
Do you grind you own grain or is it ground at the shop?
Can you describe your doughing in process?

I get a very consistent 84% to 86% mash efficiency with a corresponding 77% to 79% brew house efficiency. The first thing you want to start watching is your volumes throughout the process. The more accurate you can measure the volumes, the better your chances of reducing your variability. You will want to make sure you measure your water in, water after pulling the mash basket (and allowing the excess wort to drain back in), volume into the fermenter, and any losses you are left with in the end. From this you can balance out your water volumes which is the first step to becoming consistent.

The amount of sugar that gets extracted from the grain is a function of the grind quality, dispersal of the grain in the mash water, mash pH, and any compaction of the mash during the process. The biggest factor here is the grinding of the grist. If you are getting too many uncrushed kernels, then you will not get much sugar from them. The mash water must thoroughly wet the grains and the longer it takes for the water to penetrate into the center of the kernels to dissolve the starches. Uncrushed kernels or a very coarse crush will eventually give up their sugars, but it takes quite a while.

Then you have how well the grain is dispersed as you are doughing in. If you end up with clumps, the outside of the clumps will wet and the inside will see very little water. I stir as I am feeding my crushed grain into my Anvil and then for another 3 to 5 minutes watching to see if I drag any clumps up from the bottom of the basket which I then need to break up.

Water chemistry and mash pH are a rabbit hole which people on this forum and others spend inordinate amounts of time trying to figure out. The biggest thing that will help is to know your water profile (mineral content) and use a program such as Bru'n water to help predict where your mash pH will be. Barley has a tendency to bring the mash pH of relatively soft waters to the 5.4 to 5.8 range which is good enough for most brewers. If your water is too hard, then the grains are not able to bring your pH down to that range.

Recirculation of the wort, if you do it, can be both a great help or the biggest pain in the butt. Too fast of a flow rate will cause the mash to compact giving you a stuck mash or areas where the mash water will bypass the bulk of the grains. For my Anvil, I have found a rate of around 1 liter (quart) per minute works really well at keeping the grains loose in the mash basket.

If you do not recirculate your mash water, then I would recommend using a timer and stirring the mash every 12 to 15 minutes will help make sure the mash stays 'floating' and the wort can flow around the grains to carry the sugar away from them.

The 'pour through' sparge is probably one of the least efficient ways of rinsing the sugars from the grain bed. Unless you are very careful, you will most probably get some cratering of the sparge water and then inconsistent rinsing from all areas of the grain bed.

There are some additional factors which I believe help with attaining the efficiency I am able to achieve. First, I use a filter bag to line the malt basket. This allows me to grind a little finer and, more importantly to me, makes clean up hugely easier. The finer grind and slow but steady recirculation gives a quick solubilization and conversion of the starches. The bag when lifted out compacts the spent grains to liberate more wort. Any amount of wort left with the grain is sugar which is not in the boil. If you start squeezing the bag to get more wort volume out, then you need to be careful to make the process repeatable so that that action does not become another source of variability in your process.

In short, your efficiency is controlled by extracting sugars effectively and then by reducing the sugars lost later in the process in wort left in the vessel at the end.

 

[Obi]

Wow, thank you for your detailed response, I really appreciate it.

I am recirculating during the mash, although that was generally just turning the pump on and making sure the basket doesn't overflow- I will try to measure next time and go with your rate to see if that makes a difference. My guess is my flow rate was higher than that.

I get grain milled by the shop, I haven't taken the dive to grinding my own just yet...maybe that is something that could help with consistency. I trust my LHBS, but maybe there is more to it that I could really customize for my system?

For dough in: I am usually pouring slowly with one hand while stirring the grain with a mash paddle in the other. I try to take time to make sure that all of the grain gets properly soaked and there are no areas of clumping. Once all of the grain is in, I will give the entire mash a good stir to make sure that everything is separated and steeping. I will try to pay more attention to the "bottom" grains during my dough in next time to make sure they aren't getting compacted in the process. After that I will "rake" the top third as recommended by the user manual every 15 minutes (after an initial 10 minute rest without re-circulation). Would you recommend stirring more than that?

Volumes I will admit I have just been trusting the stamped values on the sidewall. I usually fill to the closest stamped half-gallon, and then use a measuring cup to add additional water. It sounds like verifying the stamped values and keeping better track of volume in general could be a great place to start.

For water I will admit I have done zero research on my tap water, I just know it tastes good and so I was fine brewing with it... there is definitely more I can do here. I think at the very least a profile is an excellent suggestion, I think I will be more interested in the nuances of it (pH, etc.) once I have a better grasp on some of the other inconsistencies.

I really like your idea of lining the grain basket, that seems like a super simple way of increasing extraction at least a little by being able to squeeze the bag at the end- but also opens up the option of a finer grind like you mentioned. I will bring it up with my LHBS and see if that is an option...I have honestly never asked.

You have definitely given me a starting point. Again, I really appreciate your detailed response. I will watch volumes more closely and make flow adjustments to my re-circulation, also look into the options with grind and a filter bag.

I will most likely be brewing again very soon, I'm excited to give it a shot

 

[doug293cz]

You should really focus on mash efficiency rather than brewhouse efficiency, as it is mash efficiency that determines OG (along with pre/post boil volumes.) OG is fixed at the end of the boil, and brewhouse includes volume losses after the boil.

To quickly diagnose mash efficiency issues, you need to know whether the conversion efficiency, or the lauter efficiency, or both is low. Mash efficiency is equal to conversion efficiency times lauter efficiency. You can measure the conversion efficiency using the method here. Then you can use your brewing software to determine your mash efficiency. Lauter efficiency is then calculated as: lauter efficiency = mash efficiency / conversion efficiency.

Conversion efficiency should be 90% or better, and 95% or better is readily achievable. Usually the biggest factor in low conversion efficiency is too coarse a grain crush. Crushing finer, and/or mashing longer can improve conversion efficiency if crush is the issue. Dough balls from insufficient grain mixing during dough-in can reduce conversion efficiency. You might want to look a using a 24" whisk instead of a mash paddle, as whisks are better at breaking up dough balls.

Lauter efficiency depends on whether or not you sparge. For no-sparge, getting good lauter efficiency depends on getting as much wort out of the grain as possible. For moderate gravity beers (OG less than 1.060) lauter efficiency should be above 75%. For batch sparging, lauter efficiency should be around 85% or better. If fly sparging, lauter efficiency should be above 90%.

You also need accurate volume measurements. The efficiency calculations can be no better than the volume measurements that go into them.

Brew on

 

[Obi]

Oh nice, I haven't heard of using a whisk before but definitely willing to give it a shot.

I think I have just been using "efficiency" interchangeably, but I am learning there are far more kinds of efficiency than I initially appreciated.

I have been doing the no sparge with this particular setup, but I have historically been letting it drain and drip without any additional compression or squeezing of the grain. Using a bag or filter like Oginme mentioned should probably help out with that next time around.

In terms of accurate volume, what is the preferred method? Weight? Or using a measuring cup to make marks? It seems like it should be simple, but I'm honestly not sure what the best method to measure several gallons accurately is other than using a measuring cup for the entire volume. Again...back to basics...

 

[doug293cz]

Oh nice, I haven't heard of using a whisk before but definitely willing to give it a shot.

I think I have just been using "efficiency" interchangeably, but I am learning there are far more kinds of efficiency than I initially appreciated.

I have been doing the no sparge with this particular setup, but I have historically been letting it drain and drip without any additional compression or squeezing of the grain. Using a bag or filter like Oginme mentioned should probably help out with that next time around.

In terms of accurate volume, what is the preferred method? Weight? Or using a measuring cup to make marks? It seems like it should be simple, but I'm honestly not sure what the best method to measure several gallons accurately is other than using a measuring cup for the entire volume. Again...back to basics...

Making a dipstick for you system is one of the easiest ways to measure volumes, with reasonable accuracy. Use a calibrated measuring vessel to pour about a quart or half gallon at a time into your BK, and mark the dipstick each time (sharpie, notch, etc.) A lot of measuring vessels aren't all that well calibrated unfortunately. so the best way is to calibrate you measuring vessel using weight. Water weighs 8.3304 lb/gal @ 68°F (20°C), a gallon weighs a little more at lower temps and a little less at higher temps.

Brew on

 

[Oginme]

Oh nice, I haven't heard of using a whisk before but definitely willing to give it a shot.

I think I have just been using "efficiency" interchangeably, but I am learning there are far more kinds of efficiency than I initially appreciated.

I have been doing the no sparge with this particular setup, but I have historically been letting it drain and drip without any additional compression or squeezing of the grain. Using a bag or filter like Oginme mentioned should probably help out with that next time around.

In terms of accurate volume, what is the preferred method? Weight? Or using a measuring cup to make marks? It seems like it should be simple, but I'm honestly not sure what the best method to measure several gallons accurately is other than using a measuring cup for the entire volume. Again...back to basics...

I have a post on the BeerSmith forum on how I made a measuring stick for my Anvil which can be found here: http://www.beersmith.com/forum/index.php/topic,20873.0.html

You want to make sure that your water is of constant temperature and use either a calibrated measuring vessel or by weight. I fulled a cooler full of water at 68F and weighed it out by the liter into the Anvil (1 liter at 68F = 998 grams). If you like to do more complex calculations, you can use US measurements of gallons (8.33 lbs) or quarts (2.08 lbs).

 

[Obi]

I have a post on the BeerSmith forum on how I made a measuring stick for my Anvil which can be found here: http://www.beersmith.com/forum/index.php/topic,20873.0.html

Awesome, I will check it out for sure.

Thanks again to both of you for the help, I will post back here after my next batch with -hopefully- better results. Cheers!