Efficiency, Mash and Sparge

Hey guys I am having issues with my efficiency and was curious to get your thoughts on my process. I have now lowered my efficiency in my recipes to 75% because I cannot seem to master the fly sparging technique with the electric brewery we have which is pretty much based off of Kal's system from The Electric Brewery site except we have 15g HLT, 15g MT and 20g BK.
No matter what I do I cannot seem to get my pre-boil volume with staying above 1.010 when sparging!?! It's driving me crazy! I have gone down as low as 1.008 and still not been able to reach my pre-boil volume. We do 90min. mashing and as much as 60min. sparging with sparge water below 6pH. Like I said, we started out with 85% efficiency and now down to 75% and still cannot pull off the sparge process.
The only thing I can think of at this point is my mash temps. I have seen that most of the recipes and examples on here call for anywhere from 149F-150F, however I make some beers pretty low in ABV like 3.9%-5.5% and it seems if I mash in low like 149F by the time fermentation is done and the beer is ready to drink it seems real watery or less flavorful, so I have been mashing in at 154F-156F. I am pretty sure this is my problem with not getting the most out of my grain but is there a way to get flavorful session beers when mashing in at 148F-149F without them coming out real watery and dry? Thanks for the help!

You can have a low final gravity and still have a lot of sweetness. You can also get more flavor that way too because the yeast eat those sugars and produce their own flavors.
Aside from mashing high/low, I don't think that is why you are experiencing low efficiency.

Have there been any changes in equipment or technique?

Sometimes I experience low efficiency (<75%), but that is just how it works sometimes. Ain't no rhyme or reason. I usually use a generous amount of rice hulls and mash out when I can, and still sometimes experience <75% efficiency.

Do you mash out to above 165 degrees?

Grain additions like rye and wheat, oats, will all sticky up your mash. Rice hulls do wonders in this situation.

You may also be draining the mash too fast, low and slow is the way to go. Sometimes I try to rush through the mash, and end up stuck or with low efficiency... You gotta be patient when it comes to brewing if you want good results.

That is all I got off the top of my head. You know, 75% efficiency is really not that bad. But, I guess if you had ~85% before, it could be a bummer.... Good luck!

hopdoc said:

You can have a low final gravity and still have a lot of sweetness. You can also get more flavor that way too because the yeast eat those sugars and produce their own flavors.
Aside from mashing high/low, I don't think that is why you are experiencing low efficiency.

Have there been any changes in equipment or technique?

Sometimes I experience low efficiency (<75%), but that is just how it works sometimes. Ain't no rhyme or reason. I usually use a generous amount of rice hulls and mash out when I can, and still sometimes experience <75% efficiency.

Do you mash out to above 165 degrees?

Grain additions like rye and wheat, oats, will all sticky up your mash. Rice hulls do wonders in this situation.

You may also be draining the mash too fast, low and slow is the way to go. Sometimes I try to rush through the mash, and end up stuck or with low efficiency... You gotta be patient when it comes to brewing if you want good results.

That is all I got off the top of my head. You know, 75% efficiency is really not that bad. But, I guess if you had ~85% before, it could be a bummer.... Good luck!

Click to expand...

We do a 168F mash out. We also sparge for 50-65min. I have some things I am going to try, grain crush and also the water we loose due to equipment when mashing with the HERMS, I may have not calculated the loss due to hoses, coil etc. the right way. I will just have play around with it a bit. Thanks

Hope you get some experienced input on your thread. I've been struggling with low efficiency too!

I have a Kal clone and use a bcs instead of PIDs for temp control. I usually get 83 to 86% efficiency, but on occaision it will dip into the mid-high 70s. No rhyme or reason for it. In case it helps, here's my process.

I use 1.25 gal/lb of grain for strike volume, then I add in an amount to account for my HERMS coil. This is calculated by using pi*r2*h, or you can find all sorts of auto calculators on line like this one:
http://www.basic-mathematics.com/volume-of-a-cylinder-calculator.html where r is your radius (1/2 diameter)
You then convert the volume into quarts and add it to your total strike water amount.

My HLT temp is usually 16-18 degrees above my desired mash temp (i.e. 176 ish). I run the water over, dough in, then add water back to top off of my HLT and set for 158'F. When I get there (or close) I start the HERMS.

I do a single step at 158'F. I like the higher temp as it makes my beers more malty (and I think more flavorful). If I need to get more alcohol as well I bump up the grain bill. I mash for 60 minutes then raise the temp to 168'F and do a mash out at this temp for 15 minutes.

Sparging I do a modified fly (that's my name for it). I have an auto sparger attached to my mash tun and I run the pump from the HLT full and continuous. The mash tun fills until it is full and the auto sparger turns off the flow. From the mash tun to the boil kettle I run it real slow, probably 1 gallon every 5 minutes. Maybe a tad faster. I depends on how much I've been drinking and how impatient I am

When I hit my target volume + boil off amount I stop the sparge. Then you need to stir for a second or two. The heavier wort will be on the bottom and if you don't mix you'll get an innaccurate (low) preboil reading. Then proceed with your boil and all that. It is good to know your boil rate. I burn off .7gal/30 minutes. so 2.1 gal in a 90 minute boil. This varies a little based on air temp/humidity/air pressure, but it is close. So for me 13.5 gallons becomes 12.4 ish and by the time I leave the junk in the bottom I've got 11 or so in the fermenter. By the time the trub settles and I dump a bit from the conical I'm just over 10. Work backwards and you'll get the number of gallons you need to start with preboil.

Anyway, sorry for the length of the post. I hope something in it helps. If not, let me know and I'll try and be more specific.

A lot of brewers on here batch-sparge (me included). I did the whole fly-sparge thing the first few times I brewed and found it to be a royal PITA.

I did a bit of reading and figured, why not, I'll give batch-sparge a go. Turns out I got the same efficiency when I batch sparged in 5 minutes vs. 60 fly-sparging.

A bit more experimenting with crushing my own grain gave me the biggest return on efficiency. I went from 72-75% efficiency with grain bought from LHBS and online retailers. I bought a cereal-killer and started crushing my own grain. Without changing any of my process I jumped to 80% efficiency. If I get my temps right, water to grain ratio right with infusion and sparge, crush spot on, I can get 85% without much effort.

There was a thread a while ago posted by Jeebas who had the same problem the OP did. He did some experimenting with his crush, and got some pretty profound results.

https://www.homebrewtalk.com/f36/my-mill-calibration-experiment-385387/

My advice; don't sweat the fiddly small stuff. The mashing time isn't as critical as the conversion actually being done. Iodine will tell you when the conversion is done, not the clock. Give batch sparging a go and tune that crush. You will find you get good, repeatable, high efficiency results over time.

I don't think that mash temp is what would be causing your problems. My understanding is that mash temp affects which enzymes are active. Different enzymes will convert starches into sugars with different levels of fermentability. So, 149 would have more active Beta amylase and 155 would have more Alpha amylase. Both temps will convert everything given sufficient time (seems like 60 minutes is plenty). So mashing at 155-156 shouldn't be causing you troubles with efficiency (but it should affect your attenuation - which is what you want).

Also, could it be that when you're doing a small beer, with little grain, that your grain bed is too thin to get a good rinse while fly sparging and you're getting channeling? This seems like it might be happening since you're not hitting your volumes before you hit 1.010 wort. Like kblankenship11 said, give batch sparging a go and see if there's any big difference.

Have you tried a thinner mash? It can make it easier to eliminate doughballs. For small beers, I've had really good luck with doing a full volume mash. Mash with your intended boil volume + extra for grain absorption. Efficiency is a bit lower, but it makes for a quick brew day and turns out beers with better body (can't prove it, and it could be in my head, but it seems like it).

Lastly, you can check mash pH. Smaller beers often have higher percentages of crystal malts and contain roasted malts. Could it be that your actually too acidic? Or maybe too basic? I'd investigate the other stuff first, but its a thought.

Good luck!

Hey everyone,
Thanks for all the support on this. I brewed up a batch yesterday with grain that I actually decided to mill with a little more of a crush to it. It worked wonders, plus I made some changes to my sparge process. I not only hit all of my marks but my efficiency was higher than excpected. I shot for 75% and hit almost 80% and I reached my pre-boil volume without going below 1.010 as well. My pH was right on the spot at 5.3 after using the correct salts for my water profile. The sparge water pH was below 6 as well. I think the issue was seriously the grain crush and I was drawing my wort out too quickly at the start of my sparge. Thanks again guys.

Awesome! I love that feeling when you finally figure it out..... satisfaction.....
deserves one of these :