Final gravity question

specs5000 · Mar 13, 2017

Hi Everyone,
I have a question about my most recent batch. I have been getting some strange numbers and am hoping I can get some insight. I brewed a MoreBeer extract kit Sunset Pale Ale.

7 lbs Ultralight Malt Extract
.5 lb Dry Light Malt Extract
.25 lb Maltodextrin
.5 lbs Carastan
.5 lbs Carapils

5 gal batch, estimated OG was 1.048-1.053.

So I went through my brewing, all seemed normal, but my OG measurement was 1.070. There was a lot of suspended material in the sample tube, and I was getting pressed for time and tired so I just went ahead and pitched. Wyeast 1056 with a starter. Fermentation took off fine. Now 2 weeks later I have taken a sample and the gravity is 1.020. I think the beer tastes fine, although it is super cloudy prior to cold crashing, fining, etc.

So now I am sitting here trying to figure out what I did that messed up my measurement. I am thinking that I must have messed up my initial water volume and ended up with a more concentrated wort than I intended.

My dumb question is, I should expect a higher final gravity, correct? Is there anything else that you could think of that would cause my numbers to be off like this? Do the ratios of OG to FG seem correct?

Thanks

flars · Mar 13, 2017

The OG according to the Brewers Friend OG calculator would be 1.068. http://www.brewersfriend.com/extract-ogfg/ 1.020 is a high FG for WY 1056 but may not really be a problem with the unfermentables in the recipe. If the beer did not taste sweet the fermentation may have completed. I would have left the beer on the yeast cake for another week and raised the temperature a few degrees when there was suspicion of a problem.

Is your hydrometer calibrated? Are you correcting the SG reading for the temperature of the beer?

specs5000 · Mar 13, 2017

I will check the hydrometer today, but in the past it has been correct. I still have the beer on the yeast, so I am going to leave it a bit longer and take another measurement in a few days. I had bumped the temp up from 65 to 69 for a diacetyl rest and it has been there for 2 days.

Like I said, it tastes pretty good already, so I am more trying to better understand why my results are not matching the predicted values. This is the first batch I have had that seems off on the OG numbers.

I will look into Brewers Friend. I am surprised that there is such a large difference between the listed OG and what you calculated, so I will dig into that a bit.

Thanks

jrgtr42 · Mar 13, 2017

Like Flars, I wonder as to the amount of wort / beer you have. What's the reading on the fermenter? Did you have to top off with water in the fermenter? Was the measurement before or after topping off, and if after, did you mix well?
Also, is the recipe made for 5 gallons or 6? I did a couple Morebeer kits a ways back and I seem to remember at least one of them being for 6 gallons. (I don't have my notes handy to check...)
Also, temperature and those suspended solids in the could have ffected the OG.
Finally, for the FG, a lot of kits, especially LME extract kits, won't go any lower than about 1.020. A few reasons why, but as long as the gravity is stable over a few days, then you're done, short of pitching souring yeast, it won't go lower.
When you re-check in a few days, if it's the same, you're ready to bottle.

specs5000 · Mar 13, 2017

I am wondering too. I feel like I messed up my initial volume or I boiled off more than i realized. I don't have markings on my fermenter, and I didn't check before i pitched. I have yet to have any problems with this, so I guess I just got complacent and didn't double check things as much going through. Next time I will pay more attention. I controlled for temp on the readings. Definitely a 5 gal batch.

I am curious why LME extract kits won't ferment below 1.020. If you could explain that I would appreciate it.

flars · Mar 13, 2017

specs5000 said:
I am wondering too. I feel like I messed up my initial volume or I boiled off more than i realized. I don't have markings on my fermenter, and I didn't check before i pitched. I have yet to have any problems with this, so I guess I just got complacent and didn't double check things as much going through. Next time I will pay more attention. I controlled for temp on the readings. Definitely a 5 gal batch.

I am curious why LME extract kits won't ferment below 1.020. If you could explain that I would appreciate it.

Extract kits do ferment to a lower SG than 1.020 unless you are using a lot of unfermentables with Danstar Windsor Ale yeast.