Help figuring out efficiency problem

[D-urb]

OK this is going to be a long one. I've been brewing for 5-6 years now and consider myself a good brewer, but obviously no expert. I went through a phase where I didn't even check my gravities, I just had 4-5 recipes I really liked and things were always really close when I did check so I just kept it simple and churned out good beer. All is good until I decided to get more serious about it and start tracking things better. I also upgraded my equipment and moved to a new city about the same time....more on this later.

So, I noticed one day I was way off on my gravity is low. Through the process of trying to figure this out, I noticed my hydrometer was off and got a new one but the next brew was off as well. I checked the hydrometer against water so I know that was part of it but it didn't account for all the error and the next one was off too. Now,I've had several batches all of a sudden that I am about 55% efficiency. I've always been in the 70% + range before. Here's a run down of some of my thoughts....

1. The mash: part of my equipment upgrade was a new kettle with false bottom. I had been using a homemade cooler to tun conversion. I had a couple of brews where I had trouble keeping the temp or having it overshoot while trying to heat it up. I fixed that by giving up on direct heat and just wrapping it with a camping mat. Now I'm holding temps but still having efficiency problems.

2. Lauter: I've always done kind of a fly sparge without a fly arm. I just drizzle it on top and slowly drain off. I wonder if this process just isn't working with the new false bottom and I'm getting flow pockets? I tried to eliminate this this last time by doing a batch sparge and I got the same low efficiency. I don't have the braid in under the false bottom. Could that be necessary so as not to create a flow channel right to the spigot? I thought about going back to the cooler but my last beer was a tripel with a big grain bill and would have been tight in the cooler, one of there reasons I changed equipment. I started doing 10 gal batches and some of the higher alcohol beers made for a tight mash right to the brim.

3. Water: I moved from Philly to KC. I never had paid attention to the water before but here there is really low calcium so people have a hard time with too high pH in their mashes. I bought some pH stabilizer but that hasn't seemed to make a difference. What's even more confusing is that, when I check the pH of the mash it doesn't even register on my test strip. And not on the high end like you would expect for our water. Goes from tan to purple and my strip doesn't even change color. I wonder if I got bad strips? I've ordered a cheap electronic pH meter to see if I can sort this part out.

Otherwise, the beer has been delicious....just costing me on efficiency. My 9% triple is going to be a 7.5%. Any ideas on what the main problem is? I know its a lot of moving parts, so I've been trying to fix one thing at a time and getting no where. Thanks in advance for any advice you can give.

 

[Yooper]

If your crush hasn't changed (you're crushing it yourself), then the only thing I can think of is that it is the water. Mash pH is critical, but generally doesn't affect conversion that much.

Have you checked your mash for conversion before sparging?

 

[surffisher2a]

My first thought was also the crush of the grain.

Is it possible that your thermometer is way off ??? That was my second thought.

 

[D-urb]

I've checked the temp and it is correct. I get my grains crushed at the homebrew store and I have gone to the same place all but once. I generally do a pre boil, which is also low. I haven't checked the first runoff yet, so will do that next time. I kinda feel its gotta be the water too, just because the way the pH reads on the strip has me so confused. Hopefully the new meter will help fix that. It's just so frustrating. I got to the point where it was so consistent that I quit checking on my usual recipes and now I wonder if it's been a problem for a while and I didn't even know it. I may go back to the cooler and just see if that fixes it but I need to only manipulate one thing at a time I guess until I figure it out.

 

[porterpounder]

Going back to the cooler first is the quickest way to rule out process/equipment issues. If that is not the case then I'm with some of the others on checking the crush. Try running the grain at the shop through twice. If that doesn't change anything then go to the water. Philly has great brewing water right out of the tap for most of the city. Not sure about KC. Hopefully the pH meter will give you some answers on which way to go with water salt adjustments.

 

[WhamFish]

I had a similar problem but now I'm regularly hitting ~80% efficiency. The two things I changed were my thermometer (old one was a good 3 degrees off) and I started using RO water mixed back with a bit of my filtered tap. I found that %100 tap water for me was not hitting the correct pH.

 

[D-urb]

Well, the plot keeps getting thicker here. I checked my gravity of my tripel, which had a low SG off by about 10 pts and it's gravity now is 1.002. This actually calculates an expected alcohol %. Now that I've been searching for a cause for several beers, this has been the case every time. It's low OG and FG. Beer tastes good and doesn't seem like water, which the gravity would suggest! The funny thing is, I've bought a new hydrometer in the meantime because I originally thought that was my problem. I had a brew that was way off and checked the hydrometer to my tap water and it was .004 off. It didn't account for everything but I thought, viola! New one was maybe .998 against my tap so I figured close enough, tap water is not perfect. Now, I've had all these problems with low gravity but actually good beer and no other problems and I noticed this trend today that it's both OG and FG. Gotta be the hydrometer, right? Say the tap water is actually 1.008(would expect tap to be higher gravity than pure water), that gives me my rough error? I may have to buy some distilled water and check it against that just to see. Thoughts?

Also, regarding the pH: I've done some more research and looked at KCs water report. Alkalinity is 30 and Hardness is 130. This should be pretty good for brewing. If I add the 5.2 stabilizer, like I have been, I'm thinking that pH is not my problem. Still waiting on the meter to check next brew.

 

[D-urb]

Any thoughts on a refractometer? Are they more accurate? It'd be nice to just take the error of the gravity out of the equation. If they are better, they are only $25 so it would be worth it.

 

[Smellyglove]

Any thoughts on a refractometer? Are they more accurate? It'd be nice to just take the error of the gravity out of the equation. If they are better, they are only $25 so it would be worth it.

Stick to a hydro you know is accurate. There's a bigger chance of error-measuring with a refractometer.

How long time do you use for the continious sparge? Time is important when it comes to continious sparging.

But if you got the same efficiency with a batch sparge it seems like you have a bad conversion. What's your grist to ratio water? And do you stir? I'm guessing you use recipes where the grist contains enough enzymes to convert?

 

[D-urb]

I did continuous sparge for about 60 min and have for years. The only things that have changed recently are the water(but I had a few batches without efficiency problems after that), my pot, and my hydrometer. I'm starting to really question the hydrometer. I guess the simplest thing is to get some distilled water and check it against that? Then, if it's reading normal on that I have to assume the problem is elsewhere. I'm just starting to question it more because my beers are tasting good and don't seem to be like 1.002 FG. My last batch was one I've done before and my readings were both low but the beer tastes like it always does. I think my grains should be fine. I stir it up good at first and then let the bed set with continuous sparging and with batch sparging I stir at each step. I let beer smith do the grist to water calculations but I believe it's a standard 1.25 qt/lb grain. That hasn't changed for me in years either.

I think the pH is ok. Looking at our water report I don't see how it could be THE problem. I also just realized something too. I didn't cool the wort before checking, duh! Thats probably why my strips did not work. I didn't realize this until doing research on pH meters. I'm still going to use the electric one I ordered and cool it next time, but I don't think that will be the answer, especially since I've been using 5.2 stabilizer.

 

[Smellyglove]

If you don't trust your hydrometer then:
http://grauhall.com/catalog/index.php?cPath=44

Find the one you like. They have a good variety of different FG scales. I got one which only reads up to 1.070 (I don't make big beers that often, and you get a better resolution since it's a narrower scale) and it's been (afaik) spot on and reliable.

 

[ncbrewer]

Concerning the 5.2 Stabilizer, AJ Delange (a brewing scientist, as you probably know) posted this: “If you reword the question slightly to "Is there any reason I can't use 5.2 Stabilizer to control pH?" then the answer is yes, there are a couple. They have been set forth so often here that I'll only give the top level answer that the product does not work in most cases (no one with a pH meter on this or any other forum I'm aware of has seen it do what we expect it to do) and it adds a lot of sodium to the brew.”in this thread: https://www.homebrewtalk.com/f128/brewing-water-chemistry-primer-198460/

 

[D-urb]

I tested my hydrometer against some distilled water and it looks to be .004 off. This still doesn't account for the drastic changes I've had but it seems to put it in the range of mild problems rather than what it at first seemed.

 

[Smellyglove]

I tested my hydrometer against some distilled water and it looks to be .004 off. This still doesn't account for the drastic changes I've had but it seems to put it in the range of mild problems rather than what it at first seemed.

Just to make sure. Try it in a known gravity wort. Like 100g DME in 1000g/1L water. Should yield about 1.038. Dont boil it if you have an ok water supply.

I had a cheap hydrometer which also showed .004 off in water. But showed about 6-7 points off @1.060. I don't believe this is common but it would be worth to check to eliminate a possible unlinear-error.

 

[D-urb]

That's a good thought. Will do.

 

[Brewtus_Maximus]

I have a couple of ideas about your efficiency problem.. Hopefully they haven't been mentioned already. :cross:

I was wondering if you do a mash out? When I started to do this, I saw a noticeable bump in efficiency. I heat my mash tun over direct flame while stirring like crazy with a mash paddle for about 10 minutes after my mash is done and I have checked for conversion. Once I am getting close to 170F, I cut the flame and put the lid on and wait about 10 minutes (mash out).. Next I start the vorlauf, then sparge. If you go over 170F while heating, I would suggest vorlaufing a bit, which will lower the temp. I've found that with temp adjustments you have to be patient and wait for everything to reach an "equilibrium." I've seen temps go up 5-10 degrees AFTER I turn the gas off.

Another possibility is the math behind your efficiency calculations. I've seen people claim both high and low efficiency percentages as a result of math and measurement errors. It is understandable that many of your measurements are going to always contain a degree of uncertainty (100% accuracy in measurement is impossible), so therefore your final calculated efficiency is probably going to be +/- a few percentage points of what you calculate it to be..

Lastly, I have experienced problems with thin wort when I use too much sparge water and my pre-boil volume is too high. I know that getting your water volumes (mash + sparge) dialed in and hitting your desired pre-boil volume can be difficult to do, but is vital for hitting your target OG.

IMO I would strive for 75-80% mash efficiency (again +/- a couple points). I've seen some people claim 90+ % efficiency.. But I've talked to professional brewers that say it is highly unlikely home brewers hit efficiencies that high (prob math/measurement errors).

Hope this helps! Brew on bro! :rockin: