Possibly stuck Pilsner

[samwise]

I used to brew when I was a fair bit younger and had some very good results, but never tried lager brewing.

Seven years on and I've dusted off my equipment and given it another bash. Starting with a TC, a John bull lager and a homemade ginger beer. All of which went pretty well and are conditioning in the bottles right now.

I started another brew at the beginning of the week using a Coopers Pilsner kit. All the equipment was sterilised and rinsed several times. Some campden powder was used to dechlorinate the water.

I warmed the kit in hot water and poured into the FV with 500g of Muntons light spraymalt and 400g of brewing sugar. I disolved all of that in some boiled water with some good stirring. Then topped up with cold water to 23L, pouring from a good height to aerate the wort. This was left to cool to 21C and I took an OG of 1.042. I did away with the yeast from the kit and sprinkled in 11g of S-23 lager yeast.

The FV was left to ferment at room temperature overnight. Then the room was cooled down by opening the window before the FV went into a fridge which is kept at ~13C.

My problem is that there doesn't seem to be any fermentation since the FV was put in the fridge. Not a fart from the thing. Is it stuck? There's a good 5 or 6mm thick looking slurry at the bottom and a thin Krausen on the top. Should I warm the beer up a bit? Or just give the yeast a good rousing from the bottom of the FV? I do still have the kits yeast in the fridge. Should I rehydrate and make yeast starter with this and add that?

Is there anything obvious I've missed or done wrong? Could really do with a bit of advice on this one.

 

[Runwell-Steve]

What makes you think it's not fermenting?

You say there is slurry on the bottom and a thin Krausen on top, so I would take that as a pretty positive sign it is fermenting.

 

[samwise]

Sorry forgot to mention the airlock is pretty much level on each side. Not seen it push any water round the u-bend since it was moved. The krausen has also started to thin out. It was nice and thick before the fridge.

 

[eblis]

I've brewed 2 coopers pilsners and none of them bubbled and turned out great

 

[samwise]

Perfect. I'll leave it as it is for another week or so then.

 

[Runwell-Steve]

I wouldn't worry about what the airlock is doing, theres a good chance you have a small leak somewhere else around the lid which is letting the gas produced escape. It is the most common reason for no airlock activity, much more common than no fermentation.

Usually when I brew a pilsner I plan it for a time when I am not going to have much time to brew, so it can stay in the fridge fermenting for about 4 weeks. Seems to work for me.

 

[samwise]

My plans were a good two weeks in the fridge, then a diacetyl rest before transferring to a second FV then bring it back down to temperature again for another two weeks before bottling and conditioning.

I'm a bit paranoid about leaving it on the yeast for too long and getting autolysis occurring. Don't want to spend so much time brewing this for it to stink and taste like rubber.

How long is a safe to leave it fermenting on the yeast bed?

 

[eblis]

The longest i've left it is 17 days and bottled it.

Its my understanding that secondary fermentation is possible only after the peak fermentation activity subsides usually after 4 - 5 days, but dont take my advice as I'm still learning like you.

A way of testing if you have a leak is to press on your lid and watch the airlock, if the water goes up and then falls back to level you have leak but if it stays where it is then you have no leak.