Newbie yeast question

so i just did my 3rd homebrew the other day (oatmeal stout partial mash) and i used Safale 04 dry yeast , the past 2 times i brewed, i used safale 05. all 3 times i rehydrated the yeast, but this past time, when rehydrating it didnt foam up like the other times. i pitched the yeast anyway figuring it might not work and id have to go buy some more and repitch. but overnight it actually started to get some nice fermentation action going on and started bubbling up towards the top of the carboy. but now less than 2 days later, the foam/krausen has all fallen back down. the other 2 beers i brewed, the krausen, went alot higher, even up into the blowoff tube, and stayed for more like 3-4 days instead of just 1 . so my question is , did something go wrong? or does the different type of yeast behave differently? should i still go get some more yeast and repitch ?

just realized something that i should have mentioned, the other batches i brewed, when i rehydrated the yeast, i added some cooled wort to the rehydrated yeast, but forgot to do that this time. maybe that made the difference.

Each strain of yeast will behave differently, to a greater or lesser degree. There’s no reason to think one will be like another.

You know the yeast started. Only reason to pitch new yeast is if they didn’t finish, which I’m sure they did. Take a hydrometer reading in another day and you should see the SG is at/near where you expect it to be. But leave it alone for another week or 2 before bottling.

thanks for the replys, yeah its still bubbling pretty fast (like every 3 to 4 seconds) so thats a good sign, right?

another question i have which isnt about the yeast&fermentation (but i didnt want to start another thread) is that i added water to get my batch to 5 gallons, but i should have taken a hydrometer reading first, because i wound up getting my OG too low, directions say it should be 1.049 but i wound up at 1.042 . is that going to make a big difference in the taste of the beer? or is that not enough of a difference to worry about?

on more thing, in the directions from northern brewer, it says the optimum temp for this yeast is 64-75 degrees, its now about abut 62-63 , so maybe thats why it stopped fermenting so heavily? should i try to raise the temp?

If you used all the ingredients and ended up with the volume the recipe is intended for, you pretty much have to hit the right OG. What happened is that the wort is heavier than the water due to the sugar and it sinks to the bottom of the fermenter. When you take a reading, you get the watered down wort from the top. It’s nearly impossible to get it mixed well enough to avoid. I’ve seen it happen dozens of times.

Don’t raise the temp…it’s perfect where it is.

Don’t raise the temp…it’s perfect where it is.

thanks again, seems like maybe i’m overthinking this and worrying too much just cuz its not behaving like the other beers i made with different yeast

Yeah, I think so. Instead of freaking out, look at it as a chance to learn.

From the s-04 fact sheet
http://www.fermentis.com/fo/pdf/HB/EN/Safale_S-04_HB.pdf
[pdf]:

[quote=“Safale s-04 Fact Sheet”]A well-known, commercial English ale yeast, selected for its fast fermentation character and its ability to form a very compact sediment at the end of the fermentation, helping to improve beer clarity. [/quote]FWIW, Danstar Windsor Ale yeast has a similar description, and it flamed out really quickly when I used it (2.5 days). By contrast, US-05 (the other one you’ve been using, which I’ve recently used a few times) seems to take its time (5 - 7 days).

[quote=“Denny”]When you take a reading, you get the watered down wort from the top. It’s nearly impossible to get it mixed well enough to avoid.[/quote]Interesting, and makes sense. Makes me wonder if I should take a second gravity reading after transferring to secondary (one sample is only half a glass anyway :wink: ), and if my brews aren’t as well-attenuated as I thought.

A reading taken from secondary (why are you doing a secondary, anyway?) obviously won’t give you an accurate OG. When you use extract, it’s best to either calculate the OG of an original recipe or just accept what the kit tells you it should be.

So far I’ve had so many problems as Denny mentioned where it is very hard to get the wort/beer mixed up well enough to get a believable OG readings. So I quit trying to get it, I figured with extract kits there wasn’t a thing I could do about it one way or the other (other than get stressed out about it), and I also didn’t want to risk infection by trying to grab a sample. About the only thing it would be is a data reference point, and a way to calculate ABV% at the end.