Missed gravity

[newtobrew1981]

Hi tried brewing an IPA yesterday and Missed my og by 13 points mash temp was 152 sparge water was 168 60 min mash 60 min boil mash gravity was 1069 mash ph was 5.1 which I know is low. Grainbill was 11.5 lbs pale malt, 1 lb 1.5 oz munich2 ,10 oz caramel 60L. Used ro water with the pale ale profile on brunwater. I used the same profile a week ago to brew a pale ale and hit my numbers right on. Which I why I'm confused as to what happened. My expected og was 1065 I hit 1052. My volume into fermenter was correct. Any help with this would be great thanks.

 

[RM-MN]

The biggest factor in mash efficiency is the milling of the grains. If the mill was adjusted between batches or you got the grains from a different place, that can be the difference. I'm an advocate for owning your own mill to avoid these inconsistencies. While not as fast or pretty to look at a Corona mill can be pretty effective. http://www.discounttommy.com/p-189-...er-for-wheat-grains-or-use-as-a-nut-mill.aspx

The second factor is in the sparging. If you fly sparge you might have had some channeling which means that a lot to sugar was left in the grains. Switching to batch sparging might be the answer to this. While there can be a little less efficiency with batch sparging the consistency may be worth it to you.

 

[newtobrew1981]

No my crush was the same no adjustment made grains were the same but I do use a hose for recirc and fly sparging but it seems to me that my mash gravity was also low if I'm looking for a og of 1065 shouldn't my mash og be a lot higher than 1069

 

[newtobrew1981]

I underlet as well but did not stir the grains when I mashed in so that could also be a prob I guess. Do people usually stir the grains after underletting

 

[RM-MN]

I've never done underletting but it would seem that any time you add water to grains there is a possibility of getting "doughballs" where wet grain surrounds some dry grain. I notice them as I add grains to the water and stir them apart with a wire whisk.

 

[kh54s10]

I have never underlet a mash, so no direct experience, but I would hazard a guess that yes that was the cause of the low gravity. I suspect that you did in fact have grain that didn't get wet.

Actually I would bet money that you had doughballs.

 

[newtobrew1981]

All of the grain seemed wet when I emptied the mash tun.

 

[newtobrew1981]

What about the low ph in my mash cold that have an effect

 

[kh54s10]

All of the grain seemed wet when I emptied the mash tun.

But you don't know for how long the middle was wet. I still suspect that it was at least dry for a good portion of the mash time.

pH would have some effect, but I doubt anything significant. I have been brewing 6 3/4 years and have yet to take a pH reading.

 

[newtobrew1981]

Yeah the more I think about it your probably right. this is my second all grain batch the first time I stirred the mash when I doughed in. this time I did not. and as far as I remember that's the only thing I did different. Thanks for the help will be making sure all grain is wet from now on. Cheers