Beer Forum

Made a starter 15 hours ago and it looks like there is no activity. Certainly no krausen/foam on top. Looks just like when I pitched the vial. I used a vial of WLP500 in 2 liters of wort. I boiled 2 cups of dme in 2 qts of water for 10 mins with a tsp of yeast nutrients. Cooled the flask in ice bath to 70 asap and pitched the yeast. I placed the flask on the stir plate and went to bed. Today there seems to be no activity. I'm pretty sure I did everything correctly, but this is the second consecutive starter with this issue. Yeast was kept refrigerated until 1 hr before pitching. Use by date is 8-28-14. WTF?

I'd say leave it a bit longer - I've had several starters take at least 24 hours to get going. RDWHAHB.

The Mr Malty calc suggests that a vial with that expiration date is down to 28% viability, so it's going to to take a little bit longer than a vial that's just a week old.

The other possibility is it fermented out overnight and you missed all the action - the constant stirring keeps a bit of the krausen/foam down. But this seems less likely if that viability is about right.

Give it another day.

On a stirplate krausen can be not as obvious. Take a close look. Are bubbles rising off the bottom?

500 isn't known to produce a ton of krausen in the first place, plus the stir plate is likely knocking it back into solution before it can build up. I wouldn't worry about it. A lot of people have had that same issue with that strain. It can be a real slow starter as well. Give it some time & turn your stir plate down as low as you can.

Shine a flashlight on the spinning wort and try to see if you can observe any gas evolution taking place in the wort.

Another thing you can check on is to see if the wort smells yeasty (i.e. has been fermenting) or does it smell like fresh cooled wort?
If it has that distinct yeasty smell then the starter is working. If it has that cooled sweet wort aroma then the yeast have not kicked in yet (BTW, this last tip is not foolproof...YMMV).

Another way... turn off plate, insert sanitized hydrometer. Hydrometers, they're not just for beer anymore.

As others said above, the action of the stir plate knocks down the bubbles and the really active part of fermentation took place overnight and you just missed it. I haven't seen krausen on my starters more than a couple times in the last 7 - 8 years (since I started using stir plates). If you don't want to draw a sample for a hydrometer test, just look at it. If fermentation has taken place, the starter wort will be much lighter than it was when you first pitched the yeast. This is due to all that new yeast in suspension.

Thanks all. As I suspected, I was being a bit paranoid. This was my first 10 gallon batch my last batch had dead yeast that never got started. I live in Phoenix and I think the 110 degree three day shipping route was more than the yeast could handle. I took the flask off of the stir plate and it instantly started releasing bubbles from the solution. I had already bought two more vials as a backup. I ended up splitting the starter between 2 fermenters and adding a vial to each for good measure. The beer has been chugging along all week and seems to be doing great.