Stuck Fermentations...Just a thought.

[johnnyboy1965]

Ive never suffered from these but I know some people do. I always thought that if the yeast is alive and there are sugars available, there is no reason for a ferment to stick. Now reading another post about light and yeast has got me thinking, maybe there is a link.
If you have had a stuck fermentation please state the light level on your stuck ferment.
ie..permenant light (very rare)
50/50 light and dark.......inside your house/spare room/kitchen...etc
total darkness.

Just a thought

 

[Cwrw666]

I usually ferment in total darkness in the airing-cupboard for most of the year. I've only ever had stuck fermentations with 2 can kits. Never with 1 can kits and never with AG. It's almost as if there's something missing in the 2 can kits...

 

[Covrich]

I always thought it was mostly down to pitching rates and Aeration, lack of areation means oxygen dissolved in the wort will not allow sufficient growth and the yeast will be sluggish and have weak cell walls (also reduces harvesting viablility)

 

[Pope]

I ferment in my kitchen. It's never covered but it isn't exposed to UV light. I had one stuck brew, which was a kit. All others have been fine.

 

[Graz]

Thought this was largely confined to Munton's kits where they don't give you enough yeast (7g?) and the quality of it is dubious. Ditch the supplied yeast for something better and of the right quantity (11g) for better results.

 

[Budgie]

I've only ever had 2 stuck fermentatios. Both were AG but I think it was down to too high a mash temperature.

 

[sven945]

I've only ever had 2 stuck fermentatios. Both were AG but I think it was down to too high a mash temperature.

Surely a too high mash temperature would just lead to less fermentable sugar so a higher final gravity, but it would be fully fermented? Just sweeter than if you'd mashed lower.

 

[Budgie]

Surely a too high mash temperature would just lead to less fermentable sugar so a higher final gravity, but it would be fully fermented? Just sweeter than if you'd mashed lower.

Yes, that's true. I'll shut up. :whistle:

 

[Slid]

Ive never suffered from these but I know some people do. I always thought that if the yeast is alive and there are sugars available, there is no reason for a ferment to stick. Now reading another post about light and yeast has got me thinking, maybe there is a link.
If you have had a stuck fermentation please state the light level on your stuck ferment.
ie..permenant light (very rare)
50/50 light and dark.......inside your house/spare room/kitchen...etc
total darkness.

Just a thought

Is there a thought here that moving a beer into a lighter area might promote yeast activity? I generally do the first 2 (or even 1) week of ferment in the dark, then rack at 2 weeks and keep in a much lighter environment for a further week.

The idea of a yeast "wake up" and subsequent fermentation "in the light" would be consistent with my observations.

Any other ideas, guys?

 

[MyQul]

I suffered my first stuck brew recently. I'm almost positive it was because I didn't culture up enough yeast from a bottle conditioned bottle of Shepard Neame1698. I fermented in the dark in my brew bag

 

[Poochops]

How did you get it going again MyQul?

 

[strange-steve]

I've never heard of light being responsible for stuck fermentation before. I use a 100w light bulb as a heater in my fermentation fridge so the fv gets quite a lot of bright light exposure. I've only ever had one stuck fermentation with a Scotch ale which never dropped below 1.024 even with the addition of fresh yeast. It was bottled over a year ago and is still flat as a millpond. No idea what happened with that one.

 

[MyQul]

How did you get it going again MyQul?

I didn't, I just bottled it, as I made a bitter with the SN yeast and a dont mind a bitter with a high gravity. However English strains are notorious for continuing to attenuate in the bottle and I think my SN has too. The first bottle I opened was a gusher so I've made sure I've chilled the rest for at least 8 hours. They all seem to be fine now

 

[Poochops]

Ah thanks, I've got two Brewferm kits stuck at the moment is why I ask. To keep this answer applicable to the thread they were brewed under a north facing bay window in semi opaque buckets, but it's where I brew everything else so I don't think that's the problem, rather I think it's down to under pitching I used extra fermentables with just the kit yeast and both had an OG of 1084, one is at presently 1024 and the other 1030 and they've been there for ten days.
I've learned a lesson here so I suppose that's something! I repitched with some Gervin which failed to rouse them at all, I put this down to the alcohol content. In a last attempt to rescue something from them I pitched a alcohol tolerant re-starter earlier, I think any Belgian character will be long gone after that!

 

[yeastinfection]

Ah thanks, I've got two Brewferm kits stuck at the moment is why I ask. To keep this answer applicable to the thread they were brewed under a north facing bay window in semi opaque buckets, but it's where I brew everything else so I don't think that's the problem, rather I think it's down to under pitching I used extra fermentables with just the kit yeast and both had an OG of 1084, one is at presently 1024 and the other 1030 and they've been there for ten days.
I've learned a lesson here so I suppose that's something! I repitched with some Gervin which failed to rouse them at all, I put this down to the alcohol content. In a last attempt to rescue something from them I pitched a alcohol tolerant re-starter earlier, I think any Belgian character will be long gone after that!

how did you get on?

 

[Poochops]

Well I made two starters 50/50 fresh wort/part brewed ale, and pitched it 24 hours later and stuck them in the airing cupboard, gave it a week and the higher one dropped about 6 points to 1.024 or thereabouts, the other didn't move any discernible amount. So I just bottled them both and am keeping my fingers crossed they don't explode. So far they're carbing up nicely, god knows what they'll taste like though I'm going to stick them in the cold garage, wait a few more weeks then I'll find out! The plan was to leave them for a good 6 months anyway, along with the Ambiorix I did a while back. There's three more Brewferm kits in the cupboard to go on as the fermenters come free, I've got a pilsner and an IPA on the go in them at the mo, thankfully fermenting out nicely!