How long can this fv safely stay like this?

[Monkhouse]

Hi, attached is a picture of my fermentasaurus fv after I had finished bottling under co2 yesterday.
In the picture it’s completely pressurised and the yeast trub undisturbed at the bottom.
Although I cleaned this fv out after the picture it occurred to me that it may be le fectly safe to leave the fv in this state for some time and then simply dump a new load of wort straight on top of the trub when I have a brewday.
I’ve never once reused yeast as I’ve always been worried about contamination/ infections but I may just have the safest method of actually doing this successfully.
How long would too long be in regards to just leaving the trub under co2 pressure until im ready to brew again?

 

[foxy]

Hi, attached is a picture of my fermentasaurus fv after I had finished bottling under co2 yesterday.
In the picture it’s completely pressurised and the yeast trub undisturbed at the bottom.
Although I cleaned this fv out after the picture it occurred to me that it may be le fectly safe to leave the fv in this state for some time and then simply dump a new load of wort straight on top of the trub when I have a brewday.
I’ve never once reused yeast as I’ve always been worried about contamination/ infections but I may just have the safest method of actually doing this successfully.
How long would too long be in regards to just leaving the trub under co2 pressure until im ready to brew again?

Why would you want to do that? Don't you use dried yeast?
In the words of your own Henry Royce. Strive for perfection in everything, Accept nothing nearly right or good enough. You spend money and time creating a beer why take a chance on spoiling it? You can dump a brew over the top of a yeast cake, but other bacteria can live in a anaerobic environment.

 

[An Ankoù]

It's an interesting proposal in theory, but just not worth it. All that stuff coating the top of the FV is going to dry rock hard and start turning into Marmite which will taint your beer.
Isn't your FV a conical with a tap at the bottom? Surely that's the way to harvest your yeast, into a sterilised flask or even a sterile jam jar or beer glass and keep it in the fridge until you're ready to use it. Around a month or so max.

 

[Monkhouse]

That particular one is indeed a conical with a tap and a yeast collector- I’ve never used it as such as it seems a faff. I do just use dried yeast yes foxy, I was under the impression that there are benefits to reusing the yeast as it starts fermenting straight away without the usual lag time?

 

[An Ankoù]

That particular one is indeed a conical with a tap and a yeast collector- I’ve never used it as such as it seems a faff. I do just use dried yeast yes foxy, I was under the impression that there are benefits to reusing the yeast as it starts fermenting straight away without the usual lag time?

Agreed, and with successive generations, it adapts to house conditions and becomes a unique yeast (for good or ill). I've heard of brewers racking off the beer and then throwing another brew straight onto the yeast cake- I think that's probably better if you've already rcked it into a secondary fermenter to leave the break material and hop debris behind. But I think the real issue is with keeping it and letting it dry out on the sides of the fermenter. If you collect half a pint of sludge in a sterilised vessel and pitch with that, you've got all the advantages and non of the risks. I've read n this forum of people keeping the sludge in jars in the fridge and then using just a teaspoon or two to start the next brew!
BUT, if you're prepared to take a risk then try it and let us know how you get on.

 

[The Baron]

I do the sterilised jar thingy as AA has mentioned and it works for me, just do not overpitch if its Kveik a couple or 3 teaspoons is enough other yeasts may need a little more as they are probably not as aggressive but I would always add a teaspoon of yeast nutrient when you pitch if possible.
Ps yeasts do mutate so I generally do not recollect only after the first pitch but the experts will tell you you can do several before a new pitch is essential

 

[Agentgonzo]

I was under the impression that there are benefits to reusing the yeast as it starts fermenting straight away without the usual lag time?

That's only true if you repitch onto the yeast straight away at the end of fermentation - ie, when it's still active.

If you leave your FV like this for a while, the yeast will go dormant and you'll still have a lag time when it wakes up again.

 

[The Baron]

I forgot to add that I would either collect the yeast for re-use or throw it away and clean the FV. Chances are it is going to get nasties in it if left for any length of time under those conditions unless you have not let any air in it but even then the yeast needs storing under good sterile conditions

 

[gyurmaember]

I would only reuse this way, if I can brew on the same day as my kegging day. I had success with 4 generations so far.

 

[The Baron]

I've done 3/4 generations Gyurmaember but prefer to keep it to 1 or 2 nowadays and as I use Kveik a lot I only pitch 1/3rd of a dry pack so get 3 goes out of 1 yeast as it prefers under pitching.
Long live Yorkshiremen(tight fisted)