Gravity and sweetness?

Brewno · 11-12-2006, 01:00 PM

I was at my LHBS yesterday and they asked how I was making out with my Oatmeal Stout. I gave them the run through and told them that I was surprised by my FG.
My OG was 1.062 and after 10 days in primary where the airlock went from 2 bubbles per second to one every 70 seconds or so I racked to secondary for another 2 weeks. On bottling day I took a couple of readings and they came out to 1.026. I thought it would be lower and My LHBS seemed surprised also.

I was a little confused when she said , "well, see if it comes out too sweet."
What the hell does that mean?

Tommy

**the_bird** · 11-12-2006, 01:05 PM

What's your recipe? That does sound a little high, i.e. you may have too many unfermented fermentables in there. I'll run it through BeerSmith if you'd like and see what your FG *should* have been.

Brewno · 11-12-2006, 01:09 PM

It's a pretty popular kit at my LHBS.

7lb John Bull Amber Malt Extract
1 lb M&F Amber dry Malt Extract
½ lb M&F Roasted Barley Malt 675 L
½ lb M&F Black Patent Malt 471 L
½ lb Chocolate Malt 338 L
1 lb Flaked oats
1 oz. Yakima Magnum Hops (bittering) 60 min.
1 oz. Fuggles (finishing) 58 mins.
Wyeast # 1099XL Whitebread Ale yeast

**the_bird** · 11-12-2006, 01:20 PM

I get an OG estimate of 1.061 (good job!) and a FG estimate of 1.018. Definately off a little. What temp did you take the FG reading at? Was this a 5 gallon batch (not 5.5, or 4.5)?

Brewno · 11-12-2006, 01:40 PM

According to my stick on thermometer the temp was 70 degrees. I got five gallons in my primary but it was considerably less in my secondary and that's where I took my sample from. When I racked to bottling bucket I had 4.5 gals.

Tommy

WAGNER BREWING · 11-13-2006, 10:49 AM

I had the same problem, and it throws off the Hydrometer reading. Take notes, so next time you can add enough water next time to the batch so that your FG will come out right.

**jezter6** · 11-13-2006, 05:26 PM

Umm, so Wagner..what did that actual mean (for us newbies out there).

My FG seemed a bit high at 1.018, but I didn't add any water after adding the original 3 gal to the wort to make 5 starting gallons.

In the end (some loss in bottling), I only ended up with a 12pk of 16oz bottles, and 27.5 12oz bottles, which was a bit less than I was expecting. SHould I have added water somewhere?

Brewno · 11-13-2006, 05:46 PM

I didn't understand that response either, but I chalked it up to lack of knowledge on my part.
I started out with 5 gallons as I normally do. Then after racking to secondary and "being careful" not to get too much sediment into my secondary, I lose a little. Then the same thing happens when I rack to a bottling bucket leaving any remaining sediment behind. Before I do that, I stick a beer thief in the carboy (secondary) and take a sample for a hydrometer reading.
I'm not following what batch size at that point has to do with the reading. It's the same batch as in my primary just with a little taken out due to racking.

Tommy

dougjones31 · 11-14-2006, 06:18 AM

If your sample came from a 4.5 gallon batch then the gravity reading would be expected to be a little higher than the Target specific gravity, because you have the same amount of the thicker unfermentables but they are floating in less water therefore the gravity is higher and never will reach the target gravity.

If you add .5 gallon of water then the gravity would be less. You are increasing the volume by 1/9th so your gravity would drop 1/9th of the difference between your gravity reading and 1.000.

(1/9 * .026) = .0028

if you add .5 gallons of water to your 4.5 gallon batch the gravity would drop to @ 1.0232. You would still be 5 points off. SO let it sit a while longer to finish up.

Brewno · 11-14-2006, 10:00 AM

Quote:

Originally Posted by dougjones31

If your sample came from a 4.5 gallon batch then the gravity reading would be expected to be a little higher than the Target specific gravity, because you have the same amount of the thicker unfermentables but they are floating in less water therefore the gravity is higher and never will reach the target gravity.

If you add .5 gallon of water then the gravity would be less. You are increasing the volume by 1/9th so your gravity would drop 1/9th of the difference between your gravity reading and 1.000.

(1/9 * .026) = .0028

if you add .5 gallons of water to your 4.5 gallon batch the gravity would drop to @ 1.0232. You would still be 5 points off. SO let it sit a while longer to finish up.

Ok, I'm gonna be stupid now

Adding water would actually "change" the composition of the brew.
Taking some brew out of the carboy shouldn't, in my view.
If that were the case then how about when you take a sample for a reading. Your hydrometer is not floating in 5 gals or even 4.5, it's floating in just a few ounces or brew. By what you have explained above, why wouldn't that reading be different than if you floated the hydrometer in a 5 gal bucket?

So by what you are saying above it would seem that a 5 gal batch of brew being racked into a bottling bucket from a carboy, would have a hydrometer reading get higher as the carboy emptied into the bottling bucket?

My batch was 5 gals. My OG reading was from 5 gals. I would say that my FG reading was from 5 gals also, just with .5 gal removed...not evaporated, just left behind. I think it's density would remain the same.

Tommy