Very Low Original Gravity After Mash, Need Quick Advice!

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I did my first all grain brew this morning. It was a small batch of a very big beer, about 8.5 lbs of grains in a 5 gallon pot. i'm only making a 2.5 gallon batch.

when i finished mashing (131 degrees for 30 min, 149 for 50 minutes), the specific gravity was only 1.020. i'm shooting for 1.080, so something has gone terribly wrong!

i'm putting it back in the mash for another hour to see what happens. I could use any advise ASAP! My guess is that the grains were not crushed or something. I inspected them and they looked cracked, but they looked like any other grains i've used in partial mashes.

Any advice, especially quick advice :), would be much appreciated!
 
You need to cool the wort down to take the specific gravity. Anything over 90-100 and it will read so far off you can't do a temperature correction. Just take enough out to fill the testing cylinder and begin boiling the rest. After a few minutes check the temps on the test wort and then take a hydro reading.

With that much mash in that small size pot you should try and boil the 2nd running's into a 2nd beer if you have the fermenter space.
 
You also need to stir very well to mix up the wort, otherwise you will be taking the gravity of the final runnings (which will be low).

-a.
 
i'm cooling down the sample, it was very hot. hopefully that's the problem--easy fix :)
 
after cooling down to 59 degrees, the hydro read at .1050, which is ALOT better than 1.020. still, i was trying to get to 1.080, so i'm not exactly sure what went wrong.
 
your gravity will be higher prior to boil. multiply your preboil volume by your the last two digits of your gravity reading then divide by your post boil volume target to find out where you will be for OG

Ex: 3.5 X 50 = 175
175/2.5= 70 = 1.070. add 4 oz DME at 15 minutes left in the boil
 
your gravity will be higher prior to boil. multiply your preboil volume by your the last two digits of your gravity reading then divide by your post boil volume target to find out where you will be for OG

Ex: 3.5 X 50 = 175
175/2.5= 70 = 1.070. add 4 oz DME at 15 minutes left in the boil


i had a preboil volume of about 3 gallons, and i'm hoping to hit 2.5 post boil. since i'm doing a half batch, it will only be 2.5 anyway, so it seems i'll still be considerably low.

3x50=150/2.5=60.

i don't have any dme or lme (LHBS closed on Sunday :( ), but i do have some honey, so i guess i could make that work...
 
had to add some water and ended up at only 1.050. they beer is very dark and i think it will turn out good, just didn't get anywhere near the 1.080 i was shooting towards. i guess it won't send me to the moon like i expected :drunk:


where did i go wrong? maybe i should have just kept mashing for another hour or two. with that kind of grain bill, i expected more conversion. after the initial rest 30 min rest at 133 degrees, i mashed at 149 for 50 minutes, brought up to 167 and sparged with 1 gallon of water. i then put the grains back in the wort and mashed at 155 for another 40 minutes, once again sparging with 1 gallon of 170 degree water.
 
I guess I am wondering why the multiple step mash?

i figured that i had not mashed long enough since my SG was so low. it went up after the second mash period and i got alot more color as well.
 
I was asking more about the step mash you did first. Why not just mash ~150 for 60 minutes?
 
ahhh, yes, well a buddy of mine said that two row benefits from a protein rest at around 131 to get better enzyme activity to break up proteins. he recommended it when he heard i had 7 lbs of two row to mash. should i have gone with a straight mash at 149 for 60 minutes? i've seen this on here frequently.

i appreciate the help, i'm definitely learning on the go with some ups and downs!

Edit: On Midwest Supplies website, it says "A single step infusion mash will easily convert 2-Row, but a protein rest is recommended to improve clarity." http://www.midwestsupplies.com/american-2-row-briess.html
 
It takes practice to get your technique down. Took me a few batches(more than a few) to get my efficiency where I wanted it.
 
what can i do to improve? should i mash longer at 149 (an hour or more)?

i think i need to get a cooler to do my mash, the stove top pot is just not big enough. not sure how to keep the cooler water at a steady temp, so i'll have to study some forums on here about setting that system up...
 
If you are mashing that low a longer mash is a good idea to ensure conversion. You can always do a starch test if you aren't sure.

Why are you mashing so low though? Even if you did have full conversion you would end up with a thin, dry beer.
 
that's about all i've read about is mashing at 149, then bringing it up to 167 just before sparging. i've been trying to self teach myself since i don't have any readily accessible mentors :)
 
thanks! i understood that the a/b amylases needed a range to work together and that you could go further one way or the other, but i did not understand what result i would get from leaning toward higher or lower temps. in other words, i didn't know what impact it would have on my beer! always something more to learn! :mug:
 
Put a teaspoon of wort on a white plate. Add a drop of iodine. If it turns black then the starches aren't finished converting. It should turn brown/red. As for using a cooler you just have to calculate what temp your strike water needs to be to ensure that it ends up at the correct mashing temperature. Shut the lid and the insulation will ensure that you don't lose more than a degree or two over the course of the mash.
 
You also need to stir very well to mix up the wort, otherwise you will be taking the gravity of the final runnings (which will be low).

-a.

I second this. Stir every 20 minutes (twice in a 60 min boil). This took me from about 50% eff. to about 85%...
 
I second this. Stir every 20 minutes (twice in a 60 min boil). This took me from about 50% eff. to about 85%...

God save me if that's the case on my batch, since i added an extra 8oz of LME! :drunk:
 
Put a teaspoon of wort on a white plate. Add a drop of iodine. If it turns black then the starches aren't finished converting. It should turn brown/red. As for using a cooler you just have to calculate what temp your strike water needs to be to ensure that it ends up at the correct mashing temperature. Shut the lid and the insulation will ensure that you don't lose more than a degree or two over the course of the mash.

I'll need to pick up some iodine, as in the midst of my crisis I wished I had some but couldn't get away to pick any up.

I'm considering building one of these puppies, only maybe a 10 gallon variety:https://www.homebrewtalk.com/f51/60qt-ice-cube-mash-tun-build-cheap-simple-144475/
 
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