Estimated and actual OG differ a lot

[daenja]

I brewed a porter/stout last night and the estimated original gravity was 1.073. The actual OG that I read was 1.111! Here's the recipe that I used...

5 lbs Briess Pilsen Light DME
1.5 lbs Honey
1.5 lbs Chocolate Malt
1 lbs Caramel Malt 40L
.5 lbs Flaked Barley
4 oz Black Malt
1 oz Roasted Barley

There is one fun snafu... I accidentally pitched the yeast before taking a hydro reading. I read a couple threads that say both that it doesn't make a difference and some that says it does. Could the yeast have made my OG reading that inaccurate?

Any advice would be appreciated. Thanks.

*edited to add - I had all my specialty grains in a bag which i put into the water at about 130º F dipped the bag in and out several times and slowly let the temp rise to 170º F then pulled the grains out and let them drip as much back into the pot as I could. (I hope that makes sense, it's a bit early in the morning right now...)

 

[bdupree]

If thats a 5 gal batch, you couldn't have an og reading of 1.111 with that recipe.

 

[daenja]

It is a 5 gallon batch...

 

[Revvy]

Bdupree, yes you can, it doesn't mean it's right, but obviously if he did get that reading.

It's a pretty common issue for ANYONE topping off with water in the fermenter (and that includes partial mashes, extract or all grain revcipes) to have an error in reading the OG...In fact, it is actually nearly impossible to mix the wort and the top off water in a way to get an accurate OG reading...

Brewers get a low reading if they get more of the top off water than the wort, conversely they get a higher number if they grabbed more of the extract than the top off water in their sample.

When I am doing an extract with grain recipe I make sure to stir for a minimum of 5 minutes (whipping up a froth to aerate as well) before I draw a grav sample and pitch my yeast....It really is an effort to integrate the wort with the top off water...This is a fairly common new brewer issue we get on here...unless you under or over topped off or the final volume for the kit was 5 gallons and you topped off to 5.5, then the issue, sorry to say, is "operator error"

More than likely your true OG is really what it's supposed to be. And it will mix itself fine during fermentation.


Undiluted wort has a quite high og, it's not until we diluute it, it can be even higer that that. The op grabbed more undilute wort than diluted, and that is why he got the reading he did.

 

[daenja]

Ah, yup. I didn't mix at all after adding water to get to 5 gallons... ops!

I didn't think I'd be able to get that much extra sugars out of the grains, especially on my first time using steeping grains!

Thanks!

 

[daenja]

Oh and, thanks for the quick responses. Now I can go to work and not rack my brain trying to figure out what happened! :cheers:

 

[BeardedBrewer]

Ah, yup. I didn't mix at all after adding water to get to 5 gallons... ops!

I didn't think I'd be able to get that much extra sugars out of the grains, especially on my first time using steeping grains!

Thanks!

I'm in the same boat, and haven't mixed after adding water to the bucket, but then taking a gravity reading.

My logic though is that if you add the wort, then the water, your gravity reading would be lower (since the water is on top). However, your reading is unnaturally high. How does that work? (Did you add water first and then wort?)

 

[daenja]

I added the wort then topped off with water.

 

[dcp27]

I'm in the same boat, and haven't mixed after adding water to the bucket, but then taking a gravity reading.

My logic though is that if you add the wort, then the water, your gravity reading would be lower (since the water is on top). However, your reading is unnaturally high. How does that work? (Did you add water first and then wort?)

I'd recommend adding your wort, taking the OG, then noting the volume and adjust your OG accordingly to how much you top off with.

Post-boil OG * Post-boil Volume = Topped-off OG * Topped-off Volume

daenja, how much water did you top off with? It sounds like you were around 2.5-3gallons post boil

 

[daenja]

That's about right, I think I started my boil off with about 3-3.5 gallons so I was left with about 2.5 gallons of wort before I topped off.

 

[daenja]

Reviving the thread as I think I might have a stuck fermentation... I checked the gravity with my hydrometer tonight and it's at 1.021 at 60° F. Tomorrow it will have been in primary for 3 weeks.

I'm not freaking out (drinking a homebrew right now ) , but would like some advice. Should I, wait? repitch? both?

I'm not in a hurry on this beer as it is a bit of a bigger beer... tasting the sample, it was good, but my socks weren't knocked off. I'm contemplating adding some cold brewed coffee to it to jazz it up a touch. Perhaps some chocolate as well. I just so happen to have a bar of organic 70% cacoa dark chocolate hanging around...

 

[dcp27]

based on your ingredients, 1.021 sounds on target to me. you can try to rouse the yeast and warm it up if you'd like, but i don't see it getting much further, even with a repitch. IMO i wouldnt bother with the cocoa, but its what you want.

 

[daenja]

Thanks for the reply and advice dcp27. I plugged the ingredients into some free online software I found this morning and the final gravity it estimated is right at 1.020. So I guess it's pretty much done as far as fermentation goes. I do think I'd like to add coffee. And with all the chocolate malt in already, I'm sure the cocoa isn't necessary.

I have read some threads on adding cold brewed coffee to porters and stouts. It seems that 1 or 2 ounces is plenty. And if the coffee flavor is too strong it will fade with time. My fiancee and I drink pretty strong coffee on a daily basis. I'm not worried that it will be too strong for our tastes, but I don't want it to over-power the porter either.

Do you have any experience adding coffee, and if so what's your recommendation?