Hefeweizen extract OG of 1.070

[TripleC223]

Hey all, I just sealed an extract hefeweizen in the fermenter. My OG came out to 1.070, which seems very high for a hefe. I was shooting for a higher ABV, and my pre-brew calculations in BeerSmith came out to 1.057, but obviously something is off.

I'll paste the recipe below. Again, this is an extract brew, so I understand there should theoretically be little room for error. Perhaps my measurement was off? I tried to mix everything well before pulling the sample with a thief. I took the sample with a hydrometer.

Steeping grains
1/2 lb. flaked wheat
1/2 lb. flaked oats (instant oatmeal)

Malt
7 lbs. Briess Bavarian wheat DME

Hops
1 oz. US Hallertau (4.3% AA)

Yeast
Mangrove Jack M20 Bavarian Yeast

Gravity temp was ~65 degrees upon measurement, as was the temperature when I pitched the yeast. This is a 5-gallon batch.

Also here's a picture of the gravity reading.

 

[singybrue]

Have you tested the accuracy of your hydrometer?
How long was your boil?
Full volume boil or top off?

 

[TripleC223]

Have you tested the accuracy of your hydrometer?
How long was your boil?
Full volume boil or top off?

Hydrometer seems to be calibrated. With plain water, it was right at 1.000.

The boil was 60 minutes at 2.5 gallons. I poured that onto another 1.5-2 gallons of water in the primary and then topped off to 5 gallon. I stirred it up with the wine thief before collecting the sample.

 

[RM-MN]

Hydrometer seems to be calibrated. With plain water, it was right at 1.000.

The boil was 60 minutes at 2.5 gallons. I poured that onto another 1.5-2 gallons of water in the primary and then topped off to 5 gallon. I stirred it up with the wine thief before collecting the sample.

Right there is your answer. The concentrated wort is very difficult to completely mix with top-off water. Most often we see people concerned about low OG as they get the sample from the top of the fermenter while the more concentrated wort sinks to the bottom. You used a wine thief and got your sample nearer the bottom and got the more concentrated wort. With extract the predicted OG is what you will get if your water volumes are correct because the malt extract has a known amount of sugar.

 

[TripleC223]

That makes sense. Is there a technique that would allow for more accurate measurements, then?

 

[howamidriving]

[/COLOR]

Right there is your answer. The concentrated wort is very difficult to completely mix with top-off water. Most often we see people concerned about low OG as they get the sample from the top of the fermenter while the more concentrated wort sinks to the bottom. You used a wine thief and got your sample nearer the bottom and got the more concentrated wort. With extract the predicted OG is what you will get if your water volumes are correct because the malt extract has a known amount of sugar.

I found this to be very true in my extract brewing days, to the point where I just stopped taking og readings and assumed the calculated value.

 

[RM-MN]

That makes sense. Is there a technique that would allow for more accurate measurements, then?

You can use a long handle big spoon and stir until your face turns blue and it might be mixed. The best way is to use the expected OG because it calculates based on the sugar in the extract. If you go all grain it will matter more because the sugars you get from the grain isn't guaranteed but you will probably not be topping off the fermenter then either so the reading you get will be accurate.

 

[skeeterman]

Hydrometer seems to be calibrated. With plain water, it was right at 1.000.

The boil was 60 minutes at 2.5 gallons. I poured that onto another 1.5-2 gallons of water in the primary and then topped off to 5 gallon. I stirred it up with the wine thief before collecting the sample.

What you did was mix horizontally instead of vertically. I use a 3 inch diameter paint mixing tool attached to an electric drill to mix both beer and wine. (yes, I am ambidextrous.) 10 seconds with the stirrer and you are good.

 

[InLimbo]

That makes sense. Is there a technique that would allow for more accurate measurements, then?

Do you have the capacity to do a full boil instead of partial boil and then topping off afterwards?

 

[Morrey]

Do you have the capacity to do a full boil instead of partial boil and then topping off afterwards?

I was going to suggest the OP looks into a way to do full boil to prevent this. Unfortunately for many this means a new kettle which may not be the answer they are looking for.

 

[Morrey]

You can use a long handle big spoon and stir until your face turns blue and it might be mixed. The best way is to use the expected OG because it calculates based on the sugar in the extract. If you go all grain it will matter more because the sugars you get from the grain isn't guaranteed but you will probably not be topping off the fermenter then either so the reading you get will be accurate.

When the OP stirred with a wine thief that tool alone won't create much turbulence or stirring action in the wort. Plus he is looking to aerate the wort, so its possible aeration was not accomplished either.

Back when I did extract and employed top off water, I bought a long baker's whisk to mix plus aerate. This worked well at that point of my brewing career.