Lager yeast fermentation

[Daniel Jackson]

Hi everyone,

Just looking for some advice.

First time using mangrove jacks M84 bohemian lager yeast for my California common. I rehydrated the yeast as per instructions (20-25c) and have fermentation chamber set up 14c. I pitched the yeast on Saturday evening. Day 2 I had some signs of fermentation but now today Day 3 it seems completely dormant and airlock bubbling reversing.. This is my first time brewing a lager , is this to be expected ? Or should I start to think about pitching again.

Any advice would be greatly appreciated. I'm just used to strong ale fermentations to date

Thanks

[FrozenWaves]

I would say the only way it can reverse bubble if your fridge temp control is cooling. Has it been maintaining constant temp, and was it alot warmer than 14 deg when you placed it in the fridge?

Have you done a gravity reading to see if fermentation has already finished (if it was pitched quite warm?)?

[Daniel Jackson]

The fridge has maintained a temperature between 14.0-14.7 so not huge movements. I placed the fermenter in the fridge at 29c, but did not pitch until the wort had chilled down to 14c.

Have just done a gravity reading the it remains constant on 12 brix (same reading as Saturday)

[Dave]

Hi Daniel

Couple of questions:

How long did it take to go from 29 deg to 14 once you had it in the fridge?

Are you measuring your temp on a strip on the outside of the fermentor or in a thermowell (inside the beer?)

[Peter Smith]

I have had liquid lagers wait 36-48 hours before forming signs of fermentation,  I would have pitched 2 packs of dry yeast for a lager.   For Liquid yeast either a 5L starter or a re pitch from yeast cake is required.

 

[Crusader-Rob]

exactly peter

never pitch your lager yeast until its at temp.

i pitch my lagers around 8-9 let it free rise to 10, and then use the brulosophy method of fermentation. then lager/gelatin in the keg and drin kabout 203 weeks after kegging (i like to let it cold condition a little bit)

minimum of 2 packs of dry yeast rehydrated is key.

if you just use one, you'll end up with stalled ferments or off flavors due to lack of healthy yeast

once i get to 1.052 i've been adding a 3rd pack as well.

I'll also say that M84 is notoriously slow to start, last time i used it i didnt see any activity for 3-4 days, and even then it had only just started to form.

[Daniel Jackson]

Hi Rob & Peter,

Thanks for your comments. I pitched the yeast at 14 degrees but I only pitched 1 packet of hydrated dry yeast.

Would you recommend adding an addition packet in the same process?

Interesting to hear about the slow start of M84 - I've never experienced a slow start so gootr to hear it can happen.

Thanks

[Crusader-Rob]

to me, the second best attribute a person can have when brewing is patience.

waiting that 2-3 weeks is hard enough, but you need to be patient with yeast, some requires more care, some is hardto work with etc.

Theres not alot of point in adding more yeast now i dont think, the first pack will have taken hold, so you could still end up with other flavors etc.

the best way to talk about yeast is a brewer brews wort, yeast brews beer. take care of it, pitch good healthy amounts, keep in controlled so it doesnt get too hot, or too cold. give it plenty of oxygen when pitching yerast too.

[Daniel Jackson]

Hi Dave,

It took around 6.5 hrs to drop the temperature. I would say put in the fridge at 4 and pitched rehydrated yeast at 10.30pm

I am measuring temperatures in a thermowell in an ss brewtech conical

[Peter Smith]

Lagers are not for nervous brewers......

[Dave]

6.5 hours seems quick to drop that far, but if you are measuring in a thermowell you should be accurate.
As mentioned earlier, the only way I know for the airlock to reverse is temperature drop inside the fermentor.
Did you oxygenate / aerate and pitch two packs of yeast?

[Grant R Baker]

+1 for the double packet of yeast on lagers...

If ye look at Beersmith starter requirements a larger starter is often 2 to 3 times larger than an ale yeast, then even if you pour in loads of yeast it takes weeks longer to ferment.

[Dave]

Hi Daniel, interested to see how you got on with this?