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When to worry about OG & FG target vs actual

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kXb

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I brew partial mash 5g batches and ferment in my keezer at the recommended optimal temp of the yeast manufacturer.

I would like to know when I need to worry about the discrepancy between my target og/fg vs actual. I'm consistently lower than targeted OG and FG is usually a little short or a little over. Here are my two most recent batches:

Czech Pils
OG target 1.05
OG actual 1.042
FG target 1.01
FG actual 1.008

Two Hearted Ale Clone
OG target 1.06
OG actual 1.056
FG target 1.012
FG actual 1.015

I had a lot of trouble with the Pils batch both in the boil process and fermentation process so I'm not at all surprised I was off. I understand that I can add DME on the front end to increase OG and gently stir up more yeast on the back end and give it another few days to reach target FG if short. My real problem is that I don't know what the trigger is to take action. And what would be the actions to take if you are over target on OG? I haven't had that problem yet but I suppose it could happen some time.

My misses haven't stopped me from enjoying my beer mind you but I would like to learn how to be more consistent in reaching target on both ends of the process. Thank you!
 

balrog

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Missing 2 pts on FG is sadly un-measurable by my old eyes and I'd call it done. Are you doing all grain I presume? 4 pts on OG is pretty close. 8 pts is far enough away to dial the software back in a bit. Are you using BeerSmith or something that gives you the OG?
 
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kXb

kXb

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I'm doing partial grain recipes found at my LHBS. They are usually anywhere from 3-6 pounds of grains steeped for ~45mins with addition of either LME or DME prior to boil. I haven't branched out to using BeerSmith or the like yet although I would like to.

So what I hear you saying is my FG in both examples given is inconsequential and my OG in the Pils I probably should have added a bit of DME to get it closer to target. In looking back at all my notes, my FG is usually within 2-3 points and my OG can be where I find the biggest spread. I don't usually check OG until my wort is already chilled. Should I check it before it comes out of the kettle??
 

kh54s10

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It sounds like you are really doing extract brews with specialty grains (steeping) A partial mash would use base grains and require a mash, usually one hour at a specific temperature.

LHBS recipes could be a little off in their predicted OG. The variance that you have listed would not worry me. As said you could use some extra dme to raise the OG.

The FG is a prediction. The 3 points you experienced, IMO, are within the range of the accuracy of just reading a hydrometer. Unless it is way off I would not worry about it. Extracts can "stick" at about 1.020 even if predicted to go to about 1.010 and not be a problem. Higher than 1.025 or so and then I would take steps to get it lower.
 

GrogNerd

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are you doing partial grain batches? or extract with steeping/specialty grains? if you're not using base grains then you don't really need to worry about your OG, as long as you hit your volumes correctly, then you can be reasonably assured you hit your OG.

if you are using base grains, then take a pre-boil gravity reading, which will give you your efficiency. determine whether to add more DME/LME from that
 
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kXb

kXb

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LHBS calls it mini mash. I thought mini mash/partial mash were the same thing! My strike temp is usually ~152-155 and it stays there for ~45mins, then I rinse grains with ~170 water, pull from heat, add extracts and boil for 60mins.

Thanks for input on FG discrepancy.
 

GrogNerd

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LHBS calls it mini mash. I thought mini mash/partial mash were the same thing! My strike temp is usually ~152-155 and it stays there for ~45mins, then I rinse grains with ~170 water, pull from heat, add extracts and boil for 60mins.

Thanks for input on FG discrepancy.
they are the same thing

the difference between those and extract with specialty grains is the presence of base grains; 2- or 6-row, Maris Otter, Golden Promise, etc

Beersmith will tell you if the grains need to be mashed. look into it or other software, it will make your life easier. Beersmith does let you try before you buy
 

balrog

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What everyone else said. I've seen diffs in OG/FG with my LHBS extract with steeping grains and mini/partial mash recipes. In all cases, the majority of gravity points comes from the 3 or 6 pounds of liquid or dry extract and you basically just don't sweat it.
 
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