White labs vials, screw top on or not when harvesting...

[bferullo]

So everything I have read on yeast harvesting says to leave whatever vessel's cap on loosely. Once I harvest, can I screw the cap on as normal or do I have leave it loose?

 

[SmokeyMcBong]

I'm not sure if this is what you mean or not but when I harvest yeast from starters, I put it back into a clean sanitized wl vial and screw a new sanitized plastic cap tight. Toss it in the fridge and basically forget about it till I need to brew again, at which time I make a starter and yada, yada, yada, RDW..something else, maybe ending in homebrew?

 

[bferullo]

thanks for the response. Some posts on harvesting mentioned off gassing, so you didn't want to seal the lid to avoid a "yeast-ie" mess. being that they will be sitting in my fridge for a bit, I was hoping to be able to seal them up tight to minimize contamination risk.

I haven't tried harvesting yet, so guess I am just trying to figure it all out beforehand.

How much do you fill the vials?

 

[azazel1024]

I've only done it once, but I screwed it down tight and no issues about 3 days since doing it (it was this weekend). If you are quite sure that the yeast has finished fermentation, there shouldn't be any gas production. If anything, assuming you brought the starter up to room temperature before pitching and harvesting, then there will be lower pressure in the vial from the gases contracting once you lowered the temperature back to fridge temps.

I filled it about 9/10ths of the way up. Looks pretty much just like it did when I bought it at my LHBS, though there is a bit more yeast in there (but not by much). I rinesed out the tube and cap with a bit of warm water and oxy when I made the starter and then before refilling it I dropped the tube and cap in to a glass filled with a water idophor mixture for about 5 minutes, dumped it and then let it air dry for 3-4 minutes before refilling it.

Can't exactly promise I didn't mess anything up with my steps, but it all looks good at the moment.

 

[bferullo]

Did you bother washing or go right from yeast cake to storage?

 

[bferullo]

So I harvested some vials. Once settled in the fridge they contain about 3/4 slurry (sludge). If I am to reuse would I just use one vial in a 1 liter starter?

 

[SmokeyMcBong]

yup, that's what I'd do.

 

[azazel1024]

I didn't wash. I made an oversized starter, cold crashed it and then poured off all except for maybe 100ml of starter on top of the yeast cake. Then swirled it up, filled the vial, capped it and put it in the fridge. I then dumped the rest of the starter in to my Belgian Single. I should have done around a 500ml starter with stir plate since my yeast vial was very new, as well as being a relatively low gravity beer. So I made a 1200ml starter, both because I was intentionally overpitching a little, but also because I wasn't sure how much of the yeast cake would actually go in to the vial.

As it was, going around 200-300ml oversized probably would have been the apropriate amount to "make extra" for the vial. But since it was my first time...

About 5 days on now the yeast is pretty well compacted and stuck together in there. I'd guess it is about 4/5ths yeast, about 1/6th liquid on top and a tiny bit (a couple of ml?) of head space.

My plan is the next time I do a belgian, I'll just make a regular starter from the vial.

I do not need to look in to the things to see just how difficult it is to freeze liquid yeast. Only because the more I think about it, the more I think "gosh it would be great to have a dozen varities on hand so I can make whatever beer I want once I get a mill, grains and some bulk hops". Otherwise, the way I typically brew, I can only keep 3-5 strains on hand, because that is all I am likely to use within a 6-8 month window (I figure much longer than that and the viability will have dropped so low to make it more of a pain to culture up a starter from the liquid yeast than it would be to by a new vial at my LHBS).

I know a chico strain and an english strain are going to get used at least every 2-3 months. Beyond that, dunno. A good belgian strain is almost certainly going to be used at least every 6 months. Maybe a good wheat strain too. Probably a safe enough bet for a lager and a bock strain as well. Beyond that, I just change up what I brew too often. Yeah, a Saison strain sounds great, but I might only brew a Saison once a year. A heff strain the same and so on.

That said, if all I can keep on hand is 3-5 varieties, so be it. Its not the end of the world if I have to buy 4-5 "use once a year" yeasts on the times I rarely use them. That and since some is seasonal I know I'll brew it 2-3 times and then not again till next year. So I guess I can always save off some yeast for the 1-2 extra batches and then now I'll not make extra for the last batch (example, Oktoberfests, I know I'll probably make 2-3 Oktoberfests in August for late September/October drinking, but then not again till next August).

 

[jahdub]

I harvest from starters, because it is way cleaner / easier. Sometimes there is off gassing if the starter wasn't mostly finished by the time I put it into mason jars to crash and decant. It isn't significant off gassing, but I could see how it could potentially be dangerous if too much pressure built up. If I give a full 2 days to my starters, there's less of an issue. I never leave anything loosely sealed.