is this diacetyl?

i've been fermenting a california common for the last 8 days at 55 degrees. used the san francisco lager from white labs, made a starter, temperature has been consistent. OG was 1.053, and a hydrometer sample today measures 1.012. I'll take another in a few days, but i am guessing it is pretty much at final gravity.

however, when i tasted the sample, it tasted sweeter than i expected. anchor steam (the beer the recipe is formed after) is pretty bitter, and this had a strange sweetness to it, especially for 1.012. it wasnt a completely sugary sweetness though, it kind of felt "thick" in the mouth, and i'm wondering if this is the "buttery" description people use to describe diacetyl. it would make sense with this type of lager yeast and a lower temperature, from what i've read.

what do you think? is now the time to raise the temp a bit for a diacetyl rest, or do i wait until i'm sure it is as final gravity? is is clear that this even diacetyl? its really tough to get taste descriptions over the internet and try to compare them to your own sensory experience.

A diacetyl rest is done when the fermentation is about 75% complete, you are way past that at this point but it would not hurt to raise the temp to get another point or two to finish the beer. I usually let my lagers go in primary for at least 3 week and then lager for 4 weeks. if you pitched at 50f and maintained that temp through completion a diacetyl should not be necessarily. Lagers will change during the conditioning and lagering stage. give it some time you could be fine.


edit sorry you mentioned a California common 50 is too cold sorry. I imagine you were fermenting around 58-60.

yeah 55 actually, although i pitched the yeast in the 60s and brought the temp down over a few hours (at the suggestion of my lhbs). and since it is a cali common, i was not planning on lagering. after a bit more research, i am thinking that i will take it out of my fermentation fridge in a few days and let it condition in the back of my cold closet (~60 degrees) for the next week or two. hopefully a slightly higher temperature and some more conditioning time will help it clean up.

well, the original description is exactly what Im experiencing at the moment, it's a perfect description really. So Im going to raise the dead instead of starting new.

As written in the original, Im tasting this thicker/sweeter than expected hydro sample. Im currently at 1.014 with Wyeast 2112, been fermenting for 18 days. Would there be any harm in doing a D-rest just to be safe?

Maybe any comments from the OP on where he ended up with his experience?

After 18 days any diacetyl should have been dealt with by now. Diacetyl is more readily removed when the yeast is active shortly following primary fermentation. Diacetyl definitely can have a mouth feel, but I have never used that to identify it. It is more much identifiable to me through the distinctive butter/butterscotch flavor profile. If it is indeed diacetyl in great enough concentration to feel, then you should also be able to taste it. Normally, if diacetyl is present 2 weeks later it is because of weak yeast during primary, an issue with fermentation temperatures, or infections like Pediococcus. My guess is your tasting something else.

Doesn't sound pike diacetyl to me. Diacetyl IS buttery...you'll know it right away if you've got it.

Buttery like fake popcorn butter flavor

Yup its pretty obvious. Hit me like a ton of bricks with 2308 lager yeast prior to diacetyl rest.

sweet, thanks guys. no movie theater popcorn here, just gotta wait through the holidays before I can bottle

Yup, if it doesn't taste like buttered popcorn or create a slick, oily feel on your teeth it's not diacetyl. It is possible you didn't use enough hops though to balance out the sweetness of the malt. You also are tasting an un-conditioned, non carbonated beer. Once conditioned and carbonated it will probably taste better and less sweet.