OG has been coming out VERY low, HELP!

Hello,

I made an all grain last night with target OG 1.069 and got an actual OG 1.030! I used about 4gal of water for mashing and 3gal for sparging. Boiled volume down to 5gal for fermenter. Mashed using a 6gal bottling bucket and grains contained in a large nylon bag, finances keeping me from having a proper setup. Temp was initially at 130F and kept climbing with boiling water additions till I finally reached my target temp of 153F over the course of 60min. Then pulled off ~4gal of wort into kettle and used stove to keep it at ~153F for another 30 min to make sure I got a good conversion. Sparged grains with 3gal at 165F and collected runnings from that into 2nd kettle also sat at ~153F for 30min. then brought both kettles to a boil. hop additions. and then used copper IC to bring to 75F and then poured into fermenter bucket, poured back and forth several times to aerate chilled wort and mix well. wort was passed through strainer to remove solids during first transfer into fermenter bucket. Made an all grain batch last week with target OG of 1.047 and got a actual OG of 1.040 using the methods above, the only difference being that I did not use the strainer. I don't believe the strainer is the culprit from what I have read, but since I couldn't seem to solve the mystery myself I figured I would ask the experts....yall. Oh, and I made sure to bob the grain bag up and down and twirl it around in the mash, with as little aeration as possible, but trying to make sure the grains were completely hydrated. Anyone have any ideas as to what could be causing such a drastically low OG?

is the culprit your thermometer (or lack of it) ?

1.030 at 153F is corrected 1.051, still off, but better.

questions:
pre boil or post boil?
temp?
evaporation?
top-off water?


also, stratification can be an issue. The first runnings of the mash tun are high, the last runnings are low - did you stir vigorously prior to taking the OG reading? this would apply to a pre-boil reading, of course. (Obviously, FG readings should not be stirred, to minimize oxidation of the finished product - and after the fermentation the results would be homogenized.)

Reaching 153 is important - it's not the end result, it's the beginning temperature. You hold your grains at 153 for an hour to achieve conversion. An iodine test might be helpful here - go to CVS, (it's behind the pharmacy counter) and get some iodine. One drop in a tiny sample of your mash (after an hour) should NOT color it black or purple, but maybe introduce the lightest of ambers. If you get a black sample, you keep mashing, as your starches haven't converted yet.


Welcome to HBT, by the way

You may want to check your thermometer by either sticking it in ice water or boiling water. I learned from another post that it could be off and your temps may be higher than you think and affecting your OG.

I am still new to the forum but I thought I'd post.

here are my suggestions:

I would have taken your reading before doing the boil. That way you could calculate your post-boil gravity if you know off hand what your boil-off rate is. This would let you make any adjustments you need by adding some DME if you come to find your efficiency is dangerously low.

I agree with the other 2 posters about temperature, but it sounds like you used your IC before taking the gravity, though it is hard to decipher (a small tip would be to avoid 'walls of text' which makes your post hard to read, try breaking it up into different chunks.)

A strainer won't effect gravity, the solids that come out of beer are going to be your hot break (proteins and stuff that coagulate and drop out, helped by irish moss, etc.) and any hop solids. Some sugar might cling to the matter in the strainer but not enough to effect gravity in my opinion. However, it might be worthwhile to disregard straining all-together because it is another step which I don't find all that necessary. Most people will just whirlpool and let everything else fall out on its own in primary.

Good suggestion on the iodine hang_glider, I was going to say that myself. However, one thing about taking your FG reading: isn't it usually best to 'de-gas' your FG reading after pulling a sample to achieve the most accuracy? Since this usually involves stirring I just wanted to clarify that, obviously it doesn't involve stirring the entire beer and just the sample.

Thanks for the replies. In case of confusion by 'target OG' in the original post I meant 'theoretical OG'. I tested my thermometer, but it was not inaccurate. The "actual OG" readings mentioned in my original post are of the final 5gal at 75F after mixing well, so sad to say I didn't make a simple mistake (believe me I wish that was the case) and my wort really does seem to be terribly deficient in SG points. I just can't seem to account for my sudden drop in efficiency. Any other ideas about the possible culprit?

When no one is looking, drop a bag of DME ...

Since you're essentially steeping those grains in a bucket, why don't you switch over to BIAB?

I'm wondering if the grains were tightly packed in the bag, meaning that they didn't get thoroughly wetted inside, didn't get to the correct temperature inside, and therefore didn't get converted.

Yooper said:

I'm wondering if the grains were tightly packed in the bag, meaning that they didn't get thoroughly wetted inside, didn't get to the correct temperature inside, and therefore didn't get converted.

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I think you are onto something here. I had this problem when I attempted my first all-grain with a too-small bag, my wort was practically negative SRM and probably less dense than tap water. Most likely his 'large' nylon bag is really a 'large' hop bag that isn't allowing the grain to be stirred in the water.

2 things I gathered from your post, and one was mentioned earlier.
1. Your 153 needs to be held for at least 30 min, I usually go for an hour.
2. How was your crush? If your grain wasn't crushed properly you wouldn't be able to allow the enzymes to convert all the available starch.

Lastly, I know I said 2 things, next time try to add 170 degree water to portions of the grain as you fill your tun to make sure that everything is hydrated. Did you have any dry grain when you dumped them out? I usually add water, some grain and water then grain until I am out of grain to make sure everything is mixed without dough balls.

Don't lose heart, we will all help you get this figured out.

Again, I greatly appreciate all of your responses. I did check to make sure that the grain ball wasn't dry inside and it wasn't. I also agitated my grain bag thuroughly during the mash and sparge to try and facilitate the process.

I like the idea behind BIAB, hell I was pretty much there and didn't even realize it, thanks usfmikeb. I was considering doing it all in the kettle instead of the bucket and that would make it pretty much BIAB.

I will invest in a larger bag with a larger pore size instead of my 'large hop bag'. I read about makeing my own bag in the comments section of this link:http://www.beersmith.com/blog/2009/04/14/brew-in-a-bag-biab-all-grain-beer-brewing/
I do not have my own grain mill, my LHBS (Defalcos, Houston, Tx) milled them for me.

Thanks again for all the replies. I checked the grain ball when I was retrieving my grain bag and didn't notice any dry patches. Plus I frequently agitated the gran bag during the mash in attempt to enhance hydration and extraction. The grain bag was a tight fit for this 12lb grain bill which may have inhibited the hydration and extraction, so possibly a larger grain bag would fix things.

Thank you usfmikeb for calling BIAB to my attention, I hadn’t heard of it and it is basically what I was doing. LOL. I had even thought about doing the mash in my brew kettle to help maintain a stricter control on my temperatures. I found some encouraging comments in this link (http://www.beersmith.com/blog/2009/04/14/brew-in-a-bag-biab-all-grain-beer-brewing/) that make me believe I should get a bigger bag (possibly even make my own) and stick with the BIAB method.

Grains were milled by LHBS (Defalcos, Houston, Tx) and I don’t plan on buying a grain mill soon. Finances are the reason I perused BIAB style vs traditional all-grain brewing.

Thanks again for all the replies. I checked the grain ball when I was retrieving my grain bag and didn’t notice any dry patches. Plus I frequently agitated the gran bag during the mash in attempt to enhance hydration and extraction. The grain bag was a tight fit for this 12lb grain bill which may have inhibited the hydration and extraction, so possibly a larger grain bag would fix things.

Thank you usfmikeb for calling BIAB to my attention, I hadn’t heard of it and it is basically what I was doing. LOL. I had even thought about doing the mash in my brew kettle to help maintain a stricter temperature ramping scheme. I found some encouraging comments in this link (http://www.beersmith.com/blog/2009/04/14/brew-in-a-bag-biab-all-grain-beer-brewing/) that make me believe I should get a bigger bag (possibly even make my own) and stick with the BIAB method.

Grains were milled by LHBS (Defalcos, Houston, Tx) and I don’t plan on buying a grain mill soon. Finances are the reason I perused BIAB style vs traditional all-grain brewing.

There's a lot of BIAB material on the AG forum of this site.

How about that triple post to show just how new I am to forum posting! LOL! I thought I was experiencing computer problems, on the third submission I noticed the message that said my reply would be posted after a moderator had reviewed it. I can be a little blond sometimes. Thanks for not taunting me guys.

Alechemist said:

Thanks again for all the replies. I checked the grain ball when I was retrieving my grain bag and didn’t notice any dry patches. Plus I frequently agitated the gran bag during the mash in attempt to enhance hydration and extraction. The grain bag was a tight fit for this 12lb grain bill which may have inhibited the hydration and extraction, so possibly a larger grain bag would fix things.

Thank you usfmikeb for calling BIAB to my attention, I hadn’t heard of it and it is basically what I was doing. LOL. I had even thought about doing the mash in my brew kettle to help maintain a stricter temperature ramping scheme. I found some encouraging comments in this link (http://www.beersmith.com/blog/2009/04/14/brew-in-a-bag-biab-all-grain-beer-brewing/) that make me believe I should get a bigger bag (possibly even make my own) and stick with the BIAB method.

Grains were milled by LHBS (Defalcos, Houston, Tx) and I don’t plan on buying a grain mill soon. Finances are the reason I perused BIAB style vs traditional all-grain brewing.

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check for dry spots in your bag does not mean that you got good conversion. yooper was right on the money, with your grains in the bag and you worried about aeration = lower conversion. drape that bag over the edges, clip it down and stir with your mash paddle like beer your depends on it. dunking it up and down is not really enough, you have to stir.