Major OG miss

okoncentrerad

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I brewed an english IPA this morning and most things felt pretty good up until I took a OG sample. It was way off, estimated OG was 1.054 but it landed on 1.042 :eek: So it's going to be a pretty low ABV IPA and that's ok with me, doesn't bother me too much even if I'm wondering what went wrong...I didn't take a preboil sample this time... of course.. which I usually do. So I can't say if it was my mash efficiency that failed, but I suppose thats the most likely cause. I have had on my last brews a pretty good efficiency, close to 80%, and I didnt really do anything different this time...same kind of crushing and same kind of squeezing (BIAB) and sparging.

Anyway...my actual concern and question is this: my hopping schedule was calculated and done with the higher OG in mind, set for an IBU at around 42. How would such a big miss in gravity affect the bitterness of the beer? Much bitter of course, but would it be undrinkable? Funny thing is, I do take a tasting sample when I take the OG, and usually I think it's too bitter (I haven't really got the hang of extrapolating tasting samples to what finished beer would taste like..). BUT...this sample wasnt bitter at all, quite pleasant, and much sweeter than I usually think my beers are at this stage. So I'm not sure what to think, guess it's just wait and see?
 
Yes, the lower OG should give you more bitterness, but I think you will need to ferment it out to be sure how severe the change in bitterness is. If I was you, I would more concerned with the 12 point difference between calculated and original gravity. Assuming your equipment and process haven't changed, I might assume you mismeasured your base grain, or had some epic doughballs in that mash.
 
Thanks, I'm pretty sure there was no doughballs in the mash, I stir it quite well and a couple of times. I might have measured the grain wrongly, I didn''t think so...but if that's what's most likely then it's probably true.
 
Id go by your taste too if it didnt come across too bitter in sample than it shouldnt be you should taste some bitterness.
What was your grain bill like any adjuncts (they may need longer conversion time) especcialy if the Diastic power is low in mash?
 
Are you sure your volumes were correct? Only time I've missed by that much is when there's not nearly the boiloff expected or the time the immersion chiller leaked into the wort, diluting it quite a bit.
 
Thanks for the replies. I realize now I've been holding back some information. For my last 6-7 brews (I've been brewing quite a lot lately) I've done things "short & shoddy"-style ala Brülosophy, with 30 minutes mash and 30 minutes boil, or thereabouts. All for the reason of streamlining my brewday. It's all been working well, the last times I've more or less completed my brewday in about 2 hours, and I've had good effiency and beers have turned out rather nice (not perfect though, I'm still trying to find my way).

On all my latest brews I've been keeping things simple, from grain bill to hop schedule etc. This last one was mashed with 90% Maris Otter and 10% caramel 40, with a topping of invert sugar near end of boil. I brew small batches, about 6 liter into the fermenting vessle...which makes it possible for me to brew once a week if I want to, and be able to catch up with the drinking :D

Maybe 30 minutes wasn't enough this time to get all the conversion done? I think I've heard of ways to determine if it is but it's nothing I've looked into yet. The Maris Otter wasn't the same brand as usual I think, I think I recall a different marking on this one but it wasn't anything I was paying much attention to at the time.
 
You got it most likely not fully nconverted then. They Call it an iodine test others.here will know more about it i dont do IT.
 
Yeah...rushing the brew isn't going to help with efficiency or consistency. That being said, 30 minutes should be in the range for full conversion of 90% MO. Different maltsters' products can account for some discrepencies, but not likely enough for that big of a miss. You'd have to see a drop in efficiency from 80% to around 60% to miss by that far.
I maintain that you've missed something along the way that will account for it...either a volume issue or a mis-measurement of the grist. You mentioned sugar in the boil...are you certain that it went in before you took a gravity reading? That's the sort of thing that will account for big differences.
Another thought occurs...I've had real problems when entering new fermentables into inventory and forgetting to check the "mashed" box. That makes the calculator assume that it's 100% fermentable so that it's unaffected by your efficiency setting and will show a lower amount resulting in a higher gravity.
Why don't you post a link to the recipe and we can take a look to see if there's something amiss? We'll get to the bottom of this! ;)
 
The only time I've been wildly out was when I had 2 windows open and changed the grain bill but used the wrong window. Putting 1.9KG of extra grain in really screws up your numbers.
 
Yeah...rushing the brew isn't going to help with efficiency or consistency. That being said, 30 minutes should be in the range for full conversion of 90% MO. Different maltsters' products can account for some discrepencies, but not likely enough for that big of a miss. You'd have to see a drop in efficiency from 80% to around 60% to miss by that far.
I maintain that you've missed something along the way that will account for it...either a volume issue or a mis-measurement of the grist. You mentioned sugar in the boil...are you certain that it went in before you took a gravity reading? That's the sort of thing that will account for big differences.
Another thought occurs...I've had real problems when entering new fermentables into inventory and forgetting to check the "mashed" box. That makes the calculator assume that it's 100% fermentable so that it's unaffected by your efficiency setting and will show a lower amount resulting in a higher gravity.
Why don't you post a link to the recipe and we can take a look to see if there's something amiss? We'll get to the bottom of this! ;)

This is the recipe. As you can see it's a small brew. I've been fiddling a bit with it since brewing to see what some changes/misses can affect the outcome, but it seems weird to think I've missed the numbers on the grain bill that much on such a small brew. I added the sugar to the boil, 100% sure of that, but even if I remove the sugar from the recipe it won't get close to my actual OG.
Maybe it's a couple of small misses that adds up to this big miss; a small miss with the amount of grain, somewhat less efficency than usual, etc.
 
It's true that smaller batches are more susceptible to impact from small mistakes...a handful of grain missing makes a substantial difference in the grist. Likewise an extra pint of water here and there. I see nothing in the recipe that looks amiss. When I build something similar with different ingredients, I get the same results. I go back to volumes or maybe readings. If you're certain that those are accurate, you've got something that may be a fluke. I'd say try the exact same recipe again (at least the grain bill and method, not necessarily hops) and see if you get a better result. Might just be a matter of scratching you head over it and moving on. ;)
 
I know some base malts have a low DP than others. I bought a sack of Bairds Pale ale malt recently and i know if i use to much adjuncts in the mash ill be pushing its conversion power.

Maybe its the different MO you used that caused the slower extraction than previous. If going short and shoddy id do a 45sac rest and 30 min boil 15 more minutes maybe a few extra points. But yes i know you wany consistency:).
 
Yes I'm moving on! Good idea doing same recipe once more but different hops, that would be interesting.
 
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