How long would you keep a yeast starter for?

[Horners]

I am pretty much new to the world of liquid yeasts. I made up a 2L starter of WLP007 "Dry English Ale Yeast" back on 14th Feb. Due to factors (storms etc) I have not had chance to get the anticipated brew on and may struggle to anytime soon. I put the starter in the fridge about 5 days after it had originally gone on - just with some foil round the neck of conical flask.

Can anyone advise how best to use this eg how long can I keep it like this, anything I should do prior to using etc?

Cheers

Horners

 

[Ben034]

I am pretty much new to the world of liquid yeasts. I made up a 2L starter of WLP007 "Dry English Ale Yeast" back on 14th Feb. Due to factors (storms etc) I have not had chance to get the anticipated brew on and may struggle to anytime soon. I put the starter in the fridge about 5 days after it had originally gone on - just with some foil round the neck of conical flask.

Can anyone advise how best to use this eg how long can I keep it like this, anything I should do prior to using etc?

Cheers

Horners

Online yeast calculators will give you a rough estimate of the viability of a starter (just enter the approximate amount of cells created in the first place and the manufacture date as the date the starter was completed - 15/2/20). If it's still enough cells for your next brew go ahead. If it's under you may want to consider splitting it in half (save half in a sterilised container) and use the remaining half to make a new starter. You could even split it further. I always split a starter when buying a new liquid, chill it down, pour off the beer on top and save about 20ml in a vial. I will then use this 5/6/7 times by repeating the process. You need to ensure that your sanitation is very good for this.

In answer to your question, a week or two I would just use. Longer than this, see above.

I would place a rubber band tight around the foil but apart from that it should be fine for a few weeks.

 

[Ghillie]

You can keep it for a good while, it won’t go off (to a degree) if stored properly.

Yeast cell viability falls away somewhat during prolonged storage. To the point where building the cell count back up to the appropriate amount because economical unviable due to the cost of DME vs buying a fresh batch of liquid yeast.

I use the same calculator mentioned by @Ben034. Can’t recommend it enough. The guy is also contactable by email and gets back very quick. Answered a few of my queries regarding starters, I’m sure he could give you a definitive answer. Really nice guy. Loves talking beer!

 

[Horners]

Thanks both. To be honest I couldn't find a manufacture date on the original pack so have no idea how many cells were in the starter to begin with...if I can get it done before Sunday just going to decant 'beer' off the top and lob it in, if not then might just bite the bullet and order a new one. Problem is every time I order something online cant face not rounding it up to £65 or whatever to avoid paying postage.....definitely a false econony.

 

[Ben034]

Thanks both. To be honest I couldn't find a manufacture date on the original pack so have no idea how many cells were in the starter to begin with...if I can get it done before Sunday just going to decant 'beer' off the top and lob it in, if not then might just bite the bullet and order a new one. Problem is every time I order something online cant face not rounding it up to £65 or whatever to avoid paying postage.....definitely a false econony.

I would certainly use this one and not get another. You don't need to know the yeast packet manufacture date really. A 2l starter will be approx 280B cells (rough estimate from a calculator but it is good enough) potentially more depending on when the yeast was manufactured. You can then use the date you produced the starter (15/2) as the "manufacture" date on the calculator. This will tell you a rough number of cells that you have left in your starter.