Gravity Readings - Did I do ok?

I just took a reading after having my beer in the fermenter for 12 days. I undershot my OG on brewday by a few points, which I was told wasn't a big deal. Now my current reading is off as well. I'm fairly certain it will not change anymore during the dryhop, so how did I do? Is this close enough?


OG 1.087 (Supposed to be 1.090)
Current - 1.018 (Supposed to be 1.012)

Pretty darn close! I say you did well and not worry about it.

Did you get a consistent reading three days in a row? The yeast may still be working, that's a pretty big beer. Sometimes it takes the little guys some time to eek off those last few points on the bigger brews.

Your OG was lower by 3 points so that should mean your FG would be lower by 3 points. So really your FG is 9 points off. Not terrible but you might want to give it a little shake to get the yeast in suspension again to see if it will drop a few more points. You don't want to bottle and find out it wasn't done fermenting and have bottle bombs.

If you are dry hoping in primary, that might shake up the yeast enough to get them working again.

If you do shake it, only do it slightly.

h22lude said:

Your OG was lower by 3 points so that should mean your FG would be lower by 3 points. So really your FG is 9 points off. Not terrible but you might want to give it a little shake to get the yeast in suspension again to see if it will drop a few more points. You don't want to bottle and find out it wasn't done fermenting and have bottle bombs.

If you are dry hoping in primary, that might shake up the yeast enough to get them working again.

If you do shake it, only do it slightly.

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So attenuation is a percentage not whole units. For this small a difference h22 is probably right, but I wouldnt use that logic as a rule of thumb for other brews.

h22lude said:

Your OG was lower by 3 points so that should mean your FG would be lower by 3 points.

Click to expand...

Actually, it doesn't work that way. It seems like it would, but it doesn't. Attenuation is due to many factors, and OG is only one of the causes.

Fermentability of the ingredients, yeast strain, mash temperature, etc are play a role.

The recipe says OG of 1.090 with a FG of 1.012. That's pretty darn high attenuation- over 85%. Which might be possible, but with a high ABV like that (over 10%), it would be tough to really get that FG unless a lot of simple sugars were used and a yeast strain with high alcohol tolerance was used as well.

With an OG of 1.087, a FG of 1.018 (80% attenuation and 9.2% ABV!) is completely reasonable.

Draken said:

So attenuation is a percentage not whole units. For this small a difference h22 is probably right, but I wouldnt use that logic as a rule of thumb for other brews.

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Good point...but like you said the readings are close enough where the calculation comes out to be the same (9 points).

Thanks for the responses. It sounds like I'm going to be ok, even though this is just my first FG reading. I'm trying not to mess with it too much, so I'll probably wait until it's closer to being done dry hopping to take any more readings. I did swirl it around a bit & I am dry hopping in the primary. Unfortunately, after having it sit all night after dry hopping, I didn't see any bubbles in my star san bucket, so it looks like the yeast are all done. This is my first beer ever, so I'll be happy with anything close to average. It tasted pretty darn good though, so I'm hoping that I didn't do anything to negatively affect it during my dryhopping. Shoving pellets through the carboy opening while trying to use a muslin bag was a bear. I was dumb & forgot to use a funnel...