Low OG. Low eff. Issues?

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SteveHeff

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I have a mash tun that I feel like I'm not getting top end efficiency out of. All the brews I've put through it are getting 67%-72% efficiency. I'm not hitting my numbers the way I want to. My temp control is + or- 2 degrees all the way through. The mash tun itself is a coleman cooler. The filter system is a braided line that travels through a metal "T" and out through the valve.

I don't know if I'm losing volume because the braided line isn't in the absolute bottom of the tun. It sits about 1 inch above the bottom. I've tried to lift the mash tun for 5 minutes (at the back end) to allow it to drain completely. Even though I give it time to drain, I still think that there is more wort left in the mash tun. I can't get any more wort out of my mash tun.

I even ran an additional 4 quarts through it in a batch sparge in an attempt to gather more wort. I increased my boil off time by 15 mins to account for the extra water. I still hit 1.062 with 14 lbs of grain but I expected something more along the lines of 1.070.

Am I expecting too much from my system or should I consider rebuilding my manifold in order to obtain a higher efficiency?
 
Your efficiency's at ~70% are not bad at all. I am hitting 65% consistently, which may be low, but since it is consistent it is easy to adjust any recipe to meet my system. Worse case, it cost me a few pennies in grain per batch.
 
I'd say your expectations are off. I think 67% - 72% efficiency is a great place to be. I routinely hit in that range, and if I brewed a batch with 14 lbs. of grain, I would expect to be around 1.063, give or take. The temperature of the mash will affect attenuation, so I'd worry about it if your beers weren't finishing where you want them to. From what I have read, I think your system is fine; you just need to get comfortable with it and learn how it responds to what you are doing. After that, you can make better adjustments, which will help you hit your targets (or at least get pretty close).
 
I agree your efficiency numbers aren't bad. In general though, efficiency issues aren't always mechanical. If your water chemistry is off for a given grain bill you could be outside the optimal mash PH and get reduced efficiency. If you're confidant your water profile is good, just up your recipes a bit and sleep well...
 
Water profile is terrible where I live. This may be one the next steps I take in correcting future brews. Thanks for the fast replies. Maybe I just needed a pat on the back to tell me that things are ok.
 
You might also have too much grain absorption. Sometimes adding more grain actually yields less sugar. If you can provide the weights and volumes then your ideal efficiency could be calculated. (just knowing the volume of the tun would be helpful, but if you can provide the volume of water added for the mash, mashout and sparge that would provide a quicker answer)
For details see here:
http://woodlandbrew.blogspot.com/2012/12/when-more-grain-doesnt-add-more-sugar.html
 
Started with 26 qts in my mash tun to my 14 lbs of grain. Batch sparged with an additional 4.75 gallons in order to hit my volume numbers. I would have only sparged with 3.75 gallons but I was 1 gallon low. The mash tun is a coleman chest style cooler. I wish I remembered how large it actually is...wal-mart sells it and it's around 35 bucks. It's large. I want to say it's a 70 qt. That sounds about right.

I'm still a little bothered by of efficiency. Are there any other ways I could increase it without a major overhaul?
 
Do you perheat the cooler befor dough in? Are you recirculateing?

I ran a cooler mash tun for a while and had 75% or better all The time. My suggestion for false bottom is 1/2in copper pipe that is cut with band saw or hack saw every 1/8 in or so and about 1/4 the depth of the pipe when this is in the bottom of cooler the cuts are on the bottom of cooler this allows you to cover the whole bottom or a much larger area than you are now can post pic in a bit.
I run a RIMS setup now and we get 85% every batch. Last brew day we used Beer Smith set at 82% at 10gal potential 10.2% and ended up with 11gal At 11.4 OG. It was a Barley Wine we did 60gal and it was all that much over
 
I agree your efficiency numbers aren't bad. In general though, efficiency issues aren't always mechanical. If your water chemistry is off for a given grain bill you could be outside the optimal mash PH and get reduced efficiency. If you're confidant your water profile is good, just up your recipes a bit and sleep well...

This. My vote is for this. I moved to NY and was getting consistent 65-70% eff. Thought nothing of for the longest time but my beers had a slightly noticeable astringency, more so when young. Annoyed with this after a year of trying all sorts of other fixes, I tested my mash pH and it was over 5.8!

Now i hit my mash and sparge water with lactic acid, saw a jump in my efficiency of 10%, and that astringency is gone! My beers are much crisper on the palate now. I now routinely hit 80% efficiency and all i use is a rectangular cooler with a simple, flexible, SS braid. I also do a double batch sparge.

Anywho, check your mash pH, it really could be that simple.
 
This. My vote is for this. I moved to NY and was getting consistent 65-70% eff. Thought nothing of for the longest time but my beers had a slightly noticeable astringency, more so when young. Annoyed with this after a year of trying all sorts of other fixes, I tested my mash pH and it was over 5.8!

Now i hit my mash and sparge water with lactic acid, saw a jump in my efficiency of 10%, and that astringency is gone! My beers are much crisper on the palate now. I now routinely hit 80% efficiency and all i use is a rectangular cooler with a simple, flexible, SS braid. I also do a double batch sparge.

Anywho, check your mash pH, it really could be that simple.

I'm getting the same astringency as you. I'm actually very happy you brought that up. What kind of money are we talking by testing the water and then correcting it? And no, I'm not pre-heating my mash tun. Should I dump 1-2 gallons of hot water in my mash tun first? My strike water is usually 5-10 degrees hotter than my mash. I didn't realized that the pH could have such a profound effect on the efficiency.
 
All ways preheat the cooler even if it is just hot tap water you want it warm for the grain to go into and and if it is already warm you won't loose temp as much. image.jpg
This is the false bottom I used in my Ice Cube ice chest
 
I'm not sure on mash tun pre heating. Brew software like beer Smith has a correction for that.

But as far as water profile goes, you can send it away to be tested for twenty dollars or so.

I recommend getting some ph strips, testing your mash after ten minutes then adjust as needed with lactic acid or phosphoric acid
 
Question: could using purified "bottled" water be better than tap? Like I said previously, I have HORRIBLE tap water. There's a chemical company in town and they may or may not have contaminated the water supply (years ago) and now the water treatment facility way over treats the water. Replace bad chemicals with good chemicals? I don't exactly understand how that works, but that's the way things are here.
 
Started with 26 qts in my mash tun to my 14 lbs of grain. Batch sparged with an additional 4.75 gallons in order to hit my volume numbers. I would have only sparged with 3.75 gallons but I was 1 gallon low. The mash tun is a coleman chest style cooler. I wish I remembered how large it actually is...wal-mart sells it and it's around 35 bucks. It's large. I want to say it's a 70 qt. That sounds about right.

I'm still a little bothered by of efficiency. Are there any other ways I could increase it without a major overhaul?

5 gallon batches in a 70qt cooler? I rarely suggest mash tun geometry as an issue, but do you think that could be the case here? I.e. your mash is too shallow and it's making it hard to rinse thoroughly enough to get the sugars out?
 
I'm getting the same astringency as you. I'm actually very happy you brought that up. What kind of money are we talking by testing the water and then correcting it? And no, I'm not pre-heating my mash tun. Should I dump 1-2 gallons of hot water in my mash tun first? My strike water is usually 5-10 degrees hotter than my mash. I didn't realized that the pH could have such a profound effect on the efficiency.

Check out ward labs.com
For about $30 they'll test a sample you send them. Or you can get your municipal report from your city hall I believe for free, but then you are trusting them. I live in Florida, so I know my straight tap water is junk. That worked in my favor though because it forced me to learn about water chemistry early on. Check out the water chapter in "How to Brew", and "Designing great Beers". Both give a way to estimate mash PH without a PH meter, which are expensive and inaccurate anyway. Then for a few bucks worth of salts (gypsum, calcium chloride, epsom salt etc) and a few gallons of distilled water from your grocery store, you can cater your water profile to your grain bill. Your efficiency will likely go up but more importantly you'll brew better beer. Guys like numbers. "I get xx% efficiency, I'm awesome!" Who cares, grain isn't that expensive on the homebrewing scale. A 10% jump in efficiency might save you $2 a batch. But if your beer tastes better, what value would you place on that? Think of cooking. If you have great ingredients and a great recipe, does it matter if you're cooking on a Walmart pan? Does the $500 frying pan make the junk wrong ingredients taste better? Water is a key ingredient in beer.... :D
 
If you started with 26 quarts and added 4.75 gallons, you had 11.25 gallons in all. Assuming you collected seven gallons, you have 4.25 gallons left to account for. If your grain absorbed .15 of a gallon per pound, you could say 2.1 gallons went to that, but that still leaves you with over two gallons in your MLT.

Also, if your cooler really is 70 quarts, I would have to wonder how deep your grain bed is. A smaller MLT might allow you to better rinse your grains and improve your efficiency. Another way to improve your efficiency would be to crush your grains finer, but I wouldn't recommend that as others claim it leads to astringency.

And speaking of astringency...+1 on treating your water with acid if you are having a problem. Astringency was ruining my beers until I started treating my sparge water, and this has led to the single biggest improvement in my beers. My mash pH is usually fine without any adjustment, but I won't brew another batch without treating my sparge water. FWIW, Gordon Strong recommends phosphoric acid first and lactic acid as a distant second. In Brewing Better Beer, he writes, "Sparge water should be treated to have a pH lower than 5.8 to 6.0 (5.5 is a good choice) at sparge temperature to reduce the chances of extracting harsh and astringent tannins from the grain; pH has a much greater effect on tannin extraction than temperature."

When it comes to pH, I'd skip past the strips and go straight for a pH meter. I got the Milwaulkee Instruments pH 600, and despite a bunch of mediocre to bad reviews, it has served me well (I'm just looking to be close, not exact). I ordered some electrode storage solution and a calibration solution for it, and it works great for me. Certainly go for whatever you want, but I strongly recommend getting one and treating your sparge water if you are having astringency issues.

+1 that my efficiency improved when I started adjusting for pH. Additionally, my FG was much closer to my target as well.

I always heat my mash tun as well because I think it makes it easier to hit my mash temperature. I know there is talk of tannin extraction at temperatures above 170, and heating the mash tun makes that easier to avoid. However, I think that this goes more to a discussion about FG than efficiency. In order to heat my mash tun, I put on a pot of water (probably closer to 1/2 a gallon than a whole) when I get started, and bring it to a boil. Once I'm ready, I put it in the tun. By the time I have everything else ready, my mash tun is good to go. Those coolers really seem to hold the heat pretty well; whenever I open the lid to dump the water out, there's always some steam.
 
Very nice write up. I guess my previous post proves erroneous? Or is there still legitimate value in using bottled water?
If your water tastes bad then use bottled water. I'm blessed with decent water. You can use the equation in that post for RO, spring or tap water. Unless you have tons of alkalinity then the main driver of pH is the grain.
 
My efficiency is about the same as yours. Until recently, I was a little lower. I increased my sparge water a little, and, I think more importantly, I significantly increased how much I stir the mash when adding the sparge water. Previously, I stirred enough to get everything mixed together (or so I thought!), maybe a half a minute or so, at most. Now I stir the mash for a few minutes. The radio helps. Stir for the length of a song such as Cream's Sunshine of Your Love.

That increased my efficiency by nearly 5 percentage points.
 

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