Basics Of Making And Using A Yeast Starter

[mr_wibble]

[...]
Depends on quite a few factors. Beersmith has a yeast starter calculator and I believe there are a few others around on the web, but I generally make a 1L starter for a 23L ale.

I don't understand this "1L" starter notation, could you explain it please?

I assume that it implies a culture of yeast continually grown in a set of standardised malt-extract concentrations until the volume of water in the concentration is 1 litre.

But you can't just dump your yeast packet into 1 litre of water with XXX grams of Dried Malt Extract (DME) right?
There's steps involved over several days?

OK, this: http://www.howtobrew.com/section1/chapter6-5.html says add 1/2 cup of DME to 460ml of water. And after fermentation is done, you can either pitch that, or add another 460ml of this concentration DME+water. So for a 1 Litre starter, you'd probably want to start making your starter a 3-4 days before?

thanks,
-kt

 

[Phoney]

Sure. I mix 100g of LDME with 1L of water, boil it in a flask for 10 mins with a 1/2tsp of yeast nutrient. Cool it down, add in my little bit of yeast that has been split off from a wyeast smack pack, let it ferment out for a few days, chill in the fridge for at least 24 hours, then when im ready to brew I pour off the top leaving just the little cake behind, let it warm up and then swirl it around and pitch that. Obviously I taste the starter before I start brewing so that if it's gone to poo I can postpone my brewing day until I have a healthy starter.

Yes, I could start with 50g & 500mL and step it up after a few days but I dont really see the point. If I make a 2L lager starter I step it up from 1L. Others may disagree with my method I've been doing it this way for a few years now and never had an infection or over-pitched / under-pitched problems. *shrugs*

 

[Wolfy]

I don't understand this "1L" starter notation, could you explain it please?

I assume that it implies a culture of yeast continually grown in a set of standardised malt-extract concentrations until the volume of water in the concentration is 1 litre.

But you can't just dump your yeast packet into 1 litre of water with XXX grams of Dried Malt Extract (DME) right?
There's steps involved over several days?

OK, this: http://www.howtobrew.com/section1/chapter6-5.html says add 1/2 cup of DME to 460ml of water. And after fermentation is done, you can either pitch that, or add another 460ml of this concentration DME+water. So for a 1 Litre starter, you'd probably want to start making your starter a 3-4 days before?

As from the first post, in bold:
The usual size for a (Ale) starter is 1L to 2L.

The gravity for a starter should be between 1.030 to 1.040

A starter should be made from malt (or malt-extract)

Most often starters are made from DME.
Mixing LDME at the rate of 100g per 1L water will give the required gravity.

So a 1L starter is simply 1 liter of wort with a gravity between 1.030-1.040, yeast is pitched into it and a time later (usually 24h) the yeast has grown and can be stepped-up further or used directly. Starters need to be prepared a few days before you plan to pitch the yeast, longer if you will step them.

 

[Mardoo]

OK, a couple starter questions from a, um, starter beginner.

1) When doing a stepped starter should nutrient be added at each step? Seems no from some things I've read in Yeast and online but I'm unsure.

2) Are people adding nutrient when building the starter AND when finally pitching into the wort for the full fermentation?

3) Anyone have experience with starters for mead? Seems like it would be the same sort of process (starter wort composition same as final wort and SG between .030 and .040 etc...) but I'm hoping someone's already walked that path and can give me some hints.

Superior and delightful thank you's all around!

 

[Wolfy]

When making starters it's especially important to ensure the yeast has all its nutritional needs met, so it's a good idea to add yeast-nutrient at each step, and when it's pitched into the wort at the end.

 

[DU99]

Nice post Wolfy.. :icon_cheers:

 

[KingKong]

This post just answered my question regarding the difference in methods re pouring off the starter wort and pitching just the slurry -vs- pitching the entire starter.

I think I would prefer to pitch the slurry after refrigeration. I wont have to time everything as precisely this way.

Thanks for the great post. :icon_cheers:

 

[Wolfy]

This post just answered my question regarding the difference in methods re pouring off the starter wort and pitching just the slurry -vs- pitching the entire starter.

I think I would prefer to pitch the slurry after refrigeration. I wont have to time everything as precisely this way.

Good to hear it was useful.

Given that quick temperature changes (chilling the yeast in the fridge) can possibly cause mutation and issues with the yeast, I generally try not to refrigerate starters if I can help it, most will settle-out given a little time without having to put them in the fridge.

 

[Spiesy]

Quick question...

I made my first starter yesterday, 200g LDME to make a 2L starter, pinch of Wyeast yeast nutrient thrown in for good measure.

Dropped in Wyeast Budvar, from 4th December 2012 and activator pack... viability of around 34% from memory.

It has now been sitting on the stir plate, with a small-moderate vortex, for just under 24-hours. Ambient temperature is probably low 20's.

There is no krausen at all, zero.

Should there be?

 

[Yob]

Yes... no... maybe... not always... Sometimes.. Depends (ed) usually toward the end in my experience... patience

Has the wort changed colour? when you are getting growth the wort will lighten.

 

[Spiesy]

I don't believe it has changed colour, Yob.

Also, other tidbits of info... starter was boiler for 15mins, shit went everywhere - what a mess! It's in a 2l Schott Duran Erlenmeyer flask, aluminium foil covering... vortex is around an inch down, not massive, but I'm worried about throwing the stir bar.

 

[Yob]

vortex does not need to be huge, just has to turn the surface liquid over, do you have a hydrometer? check the gravity, if it's gone down then they are active yeah?

you can always turn it off for an hour or so and see if it starts to form a krausen, but personally I'd just let it go..

you say the viability was down, If that low I would have been very tempted to step it up from a smaller starter to begin with... whats done is done though.. give it another day and if it hasnt fired, ditch it.

:icon_cheers:

 

[Spiesy]

thanks mate. It was actually surprising to learn that I was down to just 1/3 viability after not quite 3-months.

 

[JDW81]

you can always turn it off for an hour or so and see if it starts to form a krausen

Funny, I hear all this talk of starters throwing krausen and I've never had it happen. Been making starters for years and all I ever see is heaps of CO2 being thrown off.

 

[felten]

Shine a torch into the liquid, see if there are any bubbles there that would denote activity.

 

[Spiesy]

Shine a torch into the liquid, see if there are any bubbles there that would denote activity.

will try when I get home.

 

[jonw]

Spiesy,

Did you smack the pack before pitching to the starter, and if so, did it swell?

 

[Spiesy]

Spiesy,

Did you smack the pack before pitching to the starter, and if so, did it swell?

I did, it didn't swell, and I didn't want to leave it outside of the fridge much longer than a day... so dropped her in the starter.

Got home tonight and there's a small krausen underway, with lots of bubbly, CO2 goodness rising from the bottom... will give it another 12-hours before chilling.

 

[Spiesy]

not sure how much yeast should be forming on the bottom of the flask after chilling, doesn't look like heaps... although, there's not much in those packs to start with - according to calculations I would have doubled the yeast population... perhaps I have, the bottom of the 2l flask is quite big, but I reckon there's only 1cm or so there...

 

[Spiesy]

well, guess I just have to throw what I have in...