Old yeast samples

[Covrich]

I am planning on making an oatmeal stout and in my fridge I have an old collection of Shepherds Neame Yeast..

I decided last night I would start to wake it up with a smallish starter (300ml)

Anyway the yeast was collected from the krausen and I made a starter with it and then after that fermented out decanted that into a sanitised jar in teh fridge where it has sat for a few months (end of may early June)

Anyway When I took teh jar out of the fridge the wort was really dark, the yeast sat at the bottom nicely but I decided to try the plain fermented wort and it tasted a bit sour, I know plain fermented beer can taste a little funny but I wasn't prepared to risk it so I dumped it.

Instead I decanted the dregs of two bottles which had wye valley yeast in.. probably not quite as good match for an oatmeal stout but should be okay still..

My question is would the SN yeast have probably still been okay? I have heard of plain starter worts souring.

I also heard of and may try this people putting in a single hop pellet into starters to help preserve them especially if kept longer.

 

[MyQul]

Sour taste of course indicates it might well be infected. If I was you, I'd put it in a 5L stove topper to see if it is really infected and give it a loads of conditioning time just to make sure before re-usuing it again.

What I do when harvesting yeast it also keep 1-3 bottles as 'harvesting bottles' as well as keeping an overbuild. That way if my overbuild starter goes south I've still got a couple of bottles to culture up from. They seem to last well too as the yeast has got beer (with hops of course) sitting on top of it. I dont even bother keeping these havesting bottling in the fridge. Just build them up slowly like any other bottle culture

 

[Covrich]

I dumped it. Changed my mind. I liked the beer I made with it but I found it inconsistent. Some bottles stuck to the bottom sine just stayed loose and messy up the walls of the walls of the bottles

Maybe something I did wrong

 

[MyQul]

For the best I think. There's plenty of other strains to have a go at bottle culturing

 

[Covrich]

For the best I think. There's plenty of other strains to have a go at bottle culturing

Yep.. Like I say the ESB I made has turned out nice (some bottles the yeast seems to creep in like I say)

I wonder if harvesting from bottles is a bit more of a lottery.. I also wondered about harvesting yeast in genereal.. if you harvest from teh bottom will you get more flocculant yeast, whereas if you harvest from a bottle of the same strain will you get a higher attenuating and slightly lower floculating yeast..

The Wye Valley yeast from Butty bach has been much more consistent on this occasion..

I can of course just go get more SN next time I want to use some..