so i’m trying to revive a couple packs that are old. both are the West Yorkshire strain. one pack 12 months old, the other 8 months old. best estimate is that they have 10-15% viability maybe. i made a 1.5L 1035sg starter. i was planning to pitch just one pack, but then i figured since they are both old i’ll pitch both.
i’m using a stir plate. i’ve only used it a couple times, with slurry or newer yeast. usually have the starter on there 12-20 hours, then cold crash, decant and pitch. always been successful and had a decent amount pitched.
should i expect this starter to take longer since there are so few viable yeast? it has been on almost 12 hours and it really doesn’t look like other starters had at this point. i did use fermcap because i’ve had other starters go over. perhaps that is why the appearance isn’t the same - i would expect some visible signs by now.
i did toss a starter once before when trying to revive a really old and previously frozen pack. but most starters have been great.
of course i see now that West Yorkshire is available again as this quarters’ VSS release… sounds like a test is in order…
There can be a longer lag time with old yeast. Let it ferment out and then cold crash as you would normally do. Usually with an older yeast, I like to start out with a small starter and build it up to the desired volume to avoid stressing the smaller amount of viable yeast. I think you’ll be fine as long as you have some viable yeast.
My experience bears this out. I’ve successfully started a 3 1/2 year old pack, but I started in less that 500 ml. of 1.030 wort and stepped it up several times before it was ready to use.
Ditto here. I think the oldest one I ever restarted was probably 2 years old, but by building it up with a small starter (around 250-300mL) it was fine. Getting it going was a tad slow, but once it started and I eventually got up to pitching quantity, it was fine and (to me) no different from using a fresh pack.
thanks everyone. it hadn’t occured to me to start small and build up. i will certainly do that in the future, if and when i’m holding year old yeast!
but i’m going to be a trooper and brew tonight anyhow. i’ll just do a different beer and use some other yeast i have. i am going to let this starter go a couple days to see if it eventually yields some yeast.
These are 2 pics of the same starter. One with a flash, one without. This is after 54 hours on a stir plate, then another 10 without stirring so I could see what would start to settle. I am going to cold crash it now to settle more out and then decant and pitch after I brew tonight. I think it should be fine. Definitely like the advice to start with a smaller starter and step up when using old yeast.
That isn’t the URL of an image, so you can’t drop it into the SMF “img” tags and have it work. After a minute poking around your Shutterfly page, I can’t see any way to extract a valid image URL. They may not allow it, or it may be something that only the image uploader can access. Since they’re a service that primarily exists to sell photos, my guess is they simply don’t allow it.
how can you tell when a starter is done? i was thinking that since it started to drop clear, it was probably done. since i used fermcap, i figured i was giving up the typical sign of seeing any type of krausen, so seeing that rise and fall was out.
it doesn’t seem worth taking gravity readings. i’ve never heard that to be necessary or practical. i don’t have a refractometer, just the floating variety, so taking a 5oz sample from a starter isn’t going to happen. i’ve made successful starters before, but the yeast was always much fresher and, based on Mr. Malty, going for 12-18 hours on a stir plate always worked for me.
update:
so the starter was on the stir plate for 54 hours. then 10 hours at room temp to settle. then cooled in fridge for 6 hours. decanted and pitched into a Dark Mild OG1038. Airlock bubbling after 5 hours. Going nuts after 16 hours. Going to install blow-off tube now. I’ve had explosive ferments with this (West Yorkshire) strain. I’d say, so far so good…
But I still would have to make the same batch with a fresh starter to really know…
Guess I know what I’m brewing this weekend… ;D