FG finished much lower than expected?

[Jack_O]

Hi all,

Just after an answer to a question I have regarding my beer ABV finishing alot higher than anticipated.

I have brewed a Citra Pale Ale which I anticipated to finish at 10.15 but Instead it has finished at 10.11.

My OG was also a little high (10.62) when it was estimated to be 10.59.

I used Brewer's friend recipe calculator to create my recipe. I used the Brewzilla Gen 4 to brew.

I used Verdant IPA yeast on the day and dry hopped on day 4 of fermentation. It was a very active fermentation and was temperature controlled at 20°C.

Does have one have any ideas as to why it has overshot so much? Is it simply a case of the yeast has worked too hard or I've got my effiency calculations all wrong?

I never really know how to calculate efficiency and tend to leave it at around 75% on the recipe calculator.

 

[Miraculix]

Efficiency and fg are not related.

What you want to look into is the fermentability of your wort and your specific yeast's expected attenuation. The lower the fermentability, the higher the fg. The higher the attenuation, the lower the fg.

You can control the fermentability with the mash temperature. A mash at 62c produces a highly fermentable wort, whereas a mash done at 72c creates a not so fermentable wort.

There are yeasts out there that care more about the fermentability than others. Verdant IPA wasn't so finicky based on my experience. It's a reliable workhorse yeast that does well in all scenarios.

My guess is that you created a highly fermentable wort and that resulted in your lower fg.

 

[Jack_O]

Efficiency and fg are not related.

What you want to look into is the fermentability of your wort and your specific yeast's expected attenuation. The lower the fermentability, the higher the fg. The higher the attenuation, the lower the fg.

You can control the fermentability with the mash temperature. A mash at 62c produces a highly fermentable wort, whereas a mash done at 72c creates a not so fermentable wort.

There are yeasts out there that care more about the fermentability than others. Verdant IPA wasn't so finicky based on my experience. It's a reliable workhorse yeast that does well in all scenarios.

My guess is that you created a highly fermentable wort and that resulted in your lower fg.

Appreciate that insight of knowledge.

I mashed at 68°C for 60 minutes which is my usual go to mash temperature and not experienced such differences before. There was a lot of wheat in the malt bill aswell.

Something may have just been off on the day.

It's nice to know I'm not doing too much wrong!

 

[Miraculix]

Appreciate that insight of knowledge.

I mashed at 68°C for 60 minutes which is my usual go to mash temperature and not experienced such differences before. There was a lot of wheat in the malt bill aswell.

Something may have just been off on the day.

It's nice to know I'm not doing too much wrong!

Wheat has a lot of enzymes. COuld be that you did not reach the desired temperature fast enough and the time below the desired temperature was long enough for the beta amylase form the wheat to chop the starches into highly fermentable sugars. Or your temperature reading was a bit off.

68C is a solid temperature to start with. You can go up or down from there and see what happens when you do it.

 

[dmtaylor]

I agree with @Miraculix, a lot of good info there.

Could also be hop creep. Hops contain enzymes. I assume you dry hopped? The dry hops can increase attenuation resulting in a lower FG than anticipated.