Super low attenuation with Safale US-05

Homebrew Talk - Beer, Wine, Mead, & Cider Brewing Discussion Forum

Help Support Homebrew Talk - Beer, Wine, Mead, & Cider Brewing Discussion Forum:

This site may earn a commission from merchant affiliate links, including eBay, Amazon, and others.

homebrewedipa

Active Member
Joined
Aug 19, 2010
Messages
43
Reaction score
0
Location
Seattle
Pitched a packet of US-05 into 5 gallons of 1.050 (an amber). 4 weeks later, FG is down to 1.025. This gives me an attenuation rate of like 40%. What could cause this? The first couple days of fermentation were really heavy; blowoff tube required and the whole bit.

The only thing I can think of is maybe my mash temperature was really high... I did notice that the temps were really uneven right before I started sparging; my notes say I was reading 140ish on the bottom of the tun and 160ish at the top, so if anything, that would put me well into the lower range, which should give me more fermentables, not less...

At any rate, it tastes great! So that's good news :p
 
The two most likely causes are, as you suggested, your mash temp and/or your recipe, if you'd like to share it. I've never had US-05 ever get stuck, it usually is very highly attenuating.
 
The two most likely causes are, as you suggested, your mash temp and/or your recipe, if you'd like to share it. I've never had US-05 ever get stuck, it usually is very highly attenuating.

Yeah, that's been my normal experience as well. Here's the recipe (it's nothing extraordinary though).

8lb 2-row
1.5lb C40
0.5lb Melanoiden
0.5lb Special B
0.5lb Victory

There are tons of hops though (80+ IBUs). 1.2 oz Magnum, 1oz Columbus, 1.7oz Williamette. Color is right around 18-20 SRM. I was a couple points shy of my target gravity, but pretty close.
 
Are you measuring with a hydrometer or refractometer? Have you calibrated it recently?

That's a large percentage of crystal malts, but you still ought to be finishing lower than 1.025.
 
I had a similar problem, with Nottingham. It turned out that my new thermometer was uncalibrated, reading 5°C less than the actual temp. So I tought to be at 67C but it was really at 72C.
 
Sorry for the late entry, but info for other future searchers is my goal. My inexperience had me mash a black IPA at a steamy 160 degrees and my final gravity with US 05 was still 1.010 from a very sweet and assumably "high in unfermentable sugars" wort of OG 1.067. Beer actually ended up dry. Plus I just threw the yeast on top of the crash cooled 70 degree wort without making the cream and with little more aeration than the transfer and a modest shake of the fermenter before sealing the lid. So far I was leary of using anything but liquid yeast with a large starter but I cant argue with what I saw here with my own eyes. It almost seems too good in some cases.
 
Are you measuring with a hydrometer or refractometer? Have you calibrated it recently?

That's a large percentage of crystal malts, but you still ought to be finishing lower than 1.025.

Hydrometer. I took the reading at about 70F, and adjusted for that temperature. I'm pretty confident my gravity readings are accurate. Perhaps my mash temperature was much higher than I thought and I had poor conversion. It's been bottle conditioning for a couple weeks now and I just cracked one open the other day. Flavor is pretty good; definitely low on the alcohol, very malty with a little bit of an astringent feeling on the tongue. Maybe just a tiny bit of a wet cardboard or stale taste, which I know is usually due to oxidation, however I'm not sure how that could have happened.
 
Back
Top