Super Yeast?

[jakegreen58]

I made a Lagunitas IPA clone last Saturday. I created a yeast starter (Recipe below) and applied it to the 1.074 SG wort. 7 hrs later there was some activity (a blip every half second). By Monday morning the beer was bubbling so vigorously that the small quart sized bucket the blow off tube was in couldn't contain the bubbling and was spilling onto the floor of the fermentation chamber I replaced the small bucket with a two gallon bucket and that kept it contained. By Tuesday night I replaced the blow off tube with an airlock as the bubbling had slowed to a trickle. I took a gravity reading since I had opened the top and I found that the wort was at 1.014. I didn't expect the FG to get below 1.020. Could my reading really be that low after 3 days? The beer tastes great, smells fine and I am planning on dry hopping in the secondary after 7 days. Can yeast really attenuate that well that fast?

Yeast Starter:
150g DME
1500 mL water
11g dry yeast packet of Nottingham yeast

~36 hrs after making the yeast starter, I performed a cold crash in the fridge, raised the temp back up to room temp, decanted about 500 mL off the top, swirled it well and pitched into the room temp wort.

 

[NordeastBrewer77]

Sure. I've hit FG in a few days before. Fermentation can be quite quick. What were your temps? Warm temps can make it even faster. And outta curiosity, but why make a starter w/dry?

 

[slarkin712]

There's a couple things you don't mention. How many gallons was this recipe and at what temperature did you ferment? I'll assume it was a 5 gallon batch. With your OG you would need 250-275 billion yeast cells. Considering your dry packet started with ~200 billion(commonly accepted value) and then you made a starter, you probably pitched 325-350 billion cells. So, you had more cells than you really needed, not that it's a bad thing. With that number of cells and that Nottingham can be known to ferment fast, I'd say it's not unexpected that the yeast finished that fast. If you fermented at a warm temperature, say greater than 70F, I would expect to finish very fast. Also, from my experience it seems that dry yeasts finish faster than their liquid counterparts. Finally, it's uncommon to make a yeast starter for dry yeast. You probably could have just used the one packet and it would have been enough yeast. Dry yeast is relatively inexpensive, so most people just pitch 2 packs for higher gravity beers.

 

[jakegreen58]

Fermentation temp was 68-70F inside the carboy, the actual fermentation chamber was at 62F, but the fermometer read 68-70F given the high rate of fermentation. The batch was indeed 5 gallons. I really made a starter just to see if I could. No real reason other than that. Also, I thought it would be good because I knew it was going to be a high gravity beer. I expected 1.084 but was only able to squeeze 1.074 out of it.

 

[phoenixs4r]

79.58 apparent attenuation isn't unheard of.

 

[NordeastBrewer77]

79.58 apparent attenuation isn't unheard of.

Pretty common with certain yeasts, IME.