yeast starter questions

[losman26]

You're using wyeast right?

Their suggested pitch rate for a 1.080 wort is >18 million cells per mL
http://www.wyeastlab.com/hb_pitchrates.cfm

According to the wyeast pitch rate calculator (http://www.wyeastlab.com/hb_pitchrate.cfm) a 0.674 gallon (2.55 liters) starter with one smack pack and without a stir plate, when added to 5.13 gallons of wort, will contribute 12.63 million cells per mL.

Now, assuming you decant and only pitch, say, 100 mL of starter instead of 2.55 liters, adjust the total volume of wort added to reflect the actual final volume. So you say 4.4824 gallons added wort instead of 5.13 to arrive at the correct final volume of 5.1564 (5.13 gallons plus 100 mL). This is what your pitch rate will be. According to wyeast your pitch rate is 14.21 million cells per mL. Not the full 18 that is needed. Honestly at this point I wouldn't sweat it too much. Just pitch what you've got. There's a pretty good chance that it will still ferment out just fine.

Hmm, it seems pretty close any how. I've had some brews where I under-pitched and they came out exactly fine. I've had others where I pitched a little more than probably needed, and it was a little under-attenuated.

 

[jetmac]

Do I pitch all of the liquid or decant it? How do I know when it's ready to pitch?

Either way. There is a preferred method. I don't remember if it's okay to pitch the whole thing in an ale or lager.

Is usually 12 hours enough? I plan on using it right away.

12 hours is probably the minmum. I wouldn't have a problem pitching after 12 hours.

Preferably, I would let it work for 24-36 hours then put it in your fridge until the yeast drop. Decant the liquid(all but about .5L to mix it up) and pitch just the yeast.

 

[wolverinebrewer]

Do you mean you chill when the Krausen has reached it's peak, or when it has fallen, or when it starts to fall?

I have always made starters in a half gal. growler and did not have a stir plate. I would usually try to keep it with me even taking it to work and swirl it every hour. Even during the night, I would get up periodically to swirl it.
Generally, even after the krausen had fallen, I would swirl it for a few hours just to be sure it's done. Then I would chill it and decant. Now, I have a stir plate (thanks bigbeavk) so I will not have to be so attentive to it but this was my process and it seemed to work.
Someone earlier in this thread mentioned pitching the whole thing at full krausen because it would take off in 3 hours. My decanted starters usually don't take off for about 10 hours after pitching. Since I leave the beer in the bucket for 3 weeks, I don't care about saving 7 hours and also diluting my beer.

 

[jetmac]

Is it ok to leave the starter in the fridge for that long after it finishes fermenting??

You can leave it up to about 2 weeks.

Should I put an airlock on it after it ferments or just keep the foil? ??

Leave the foil on it

I'm also assuming that after decanting the liquid, I have to bring the yeast cake back up to room temp, right??

Bring the whole shebang to the temp of your wort(within 10 degrees) then decant, leaving a little bit to mix up the yeast cake

Also, you mentioned shaking the starter. How much shaking should you do once fermentation has started?

Once per hour would be ideal

 

[jetmac]

so without a stir-plate when do you recommend pitching the starter? How much time do you think it needs? You still recommend decanting right?

The calculator has calculated in the fact that your are shaking it not using a stir plate so the amount of time is the same.

Preferably let the starter ferment 24-36 hours then refrigerate until the yeast drop. Then pitch

 

[jetmac]

Do you mean you chill when the Krausen has reached it's peak, or when it has fallen, or when it starts to fall?

Chill anytime after 24 hours but no more than 36 hours

 

[mightynintendo]

Bring the whole shebang to the temp of your wort(within 10 degrees) then decant, leaving a little bit to mix up the yeast cake

I would actually disagree with this. Bringing the whole starter up to temp will cause some yeast to become re-suspended in the wort as they wake up and begin to feed. It is my opinion that decanting should be done while the starter is still cold so as to avoid allowing the yeast to become active again before pouring them down the drain.

 

[jetmac]

I would actually disagree with this. Bringing the whole starter up to temp will cause some yeast to become re-suspended in the wort as they wake up and begin to feed. It is my opinion that decanting should be done while the starter is still cold so as to avoid allowing the yeast to become active again before pouring them down the drain.

Hmmmm....It's never been a problem for me. There should be nothing to "feed" on. And the yeast remain protected from the environment while they warm up.

 

[bigwill69]

there is soo many varing opinions on this subject and related threads.....but still wish someone would make a good long sticky for starters. proper size and several ways to prepare one.

 

[jetmac]

there is soo many varing opinions on this subject and related threads.....but still wish someone would make a good long sticky for starters. proper size and several ways to prepare one.

14 Essential Questions About Starters answered. by J.Z.

J Z talks about yeast and fermenattion

Yeast, with Chris White of Whitelabs

 

[cobbler]

Trying to make my first yeast starter following JP's How To Brew.

My starter consisted of 1/2 a cup of DME in 2 cups of boiled water. I added the washed yeast to this. I unfortunately didn't add yeast nutrient.

I don't have stir plate and I have not seen any activity from the starter in the past 36 hours.

Trying to decide if I should dump the starter and buy new yeast?

 

[mightynintendo]

yeast nutrient is not necessary to make a starter.

the fact that you have not seen any action yet could mean that your washed yeast was really low in active yeast cells. Stay the course for at least another 24 hours. If you don't see activity by then it would probably be a good idea to grab some new yeast.

 

[cobbler]

Thanks for the advice. Will keep it an eye on it through the weekend

 

[jetmac]

Trying to make my first yeast starter following JP's How To Brew.

My starter consisted of 1/2 a cup of DME in 2 cups of boiled water. I added the washed yeast to this. I unfortunately didn't add yeast nutrient.

I don't have stir plate and I have not seen any activity from the starter in the past 36 hours.

Trying to decide if I should dump the starter and buy new yeast?

Did you just use boiled water or did you boil the starter?

IMO get new yeast and start over. That procedure is to "wake up" the yeast 5-6 hours before brewing. If you want to "grow" yeast you'll need at least 1.5l starter. Then you let that starter work 15-36 hours, refrigerate a day or 2 until the yeast drop out and then decant and pitch.

You can't let a starter sit at room temp for more than 36 hours,

 

[mightynintendo]

That procedure is to "wake up" the yeast 5-6 hours before brewing. If you want to "grow" yeast you'll need at least 1.5l starter.

False. You can grow yeast just fine in a 1 liter starter.

Then you let that starter work 15-36 hours

No way. 15 hours without a stir plate is way too short. Even with a stir plate it's too short a time to get full cell count growth.

 

[jetmac]

False. You can grow yeast just fine in a 1 liter starter.

OP's OG is 1.080, so IMO, a 1.5L starter is minimum, And may not be enough with 1 pack. Using a 1L starter he needs at least 2 packs of yeast.

No way. 15 hours without a stir plate is way too short. Even with a stir plate it's too short a time to get full cell count growth.

Yes way. 15-18 hours is minimal but the growth will happen. With a stir plate it's certainly enough time.

 

[jetmac]

A 2.5 liter starter, allowed to sit with one smack pack of yeast for 24 hours, is still under-pitching a 1.080 wort.

Well sort of, you need to shake it once per hour.

 

[jetmac]

Stay the course for at least another 24 hours. If you don't see activity by then it would probably be a good idea to grab some new yeast.

Not good advice. The starter should not be allowed to sit out more than 36 hours.

 

[mightynintendo]

OP's OG is 1.080, so IMO, a 1.5L starter is minimum, And may not be enough with 1 pack. Using a 1L starter he needs at least 2 packs of yeast.

He could also start with a 1 liter starter, let the cell count grow to whatever, make another 1 liter starter with 100 mL of the starter #1 and 900 mL of fresh wort and let the cell count grow to whatever, then make another 1 liter starter with 100 mL of starter #2 and 900 mL fresh wort, let it grow to whatever, all the while refrigerating and decanting the starters. Eventually he will have his cell count and all of it could be done in 1 liter starters. in fact i know some people who do a lot of research with yeast and this is the method they use to grow yeast cells. not necessarily 1 liter starters, but 1:10 old starter to fresh wort, 24 hours exactly on the stir plate, and repeat until cell count is reached. i think in 1 liter starter, each 24 hour growth phase will produce something like 80 - 90 billion cells.

Yes way. 15-18 hours is minimal but the growth will happen. With a stir plate it's certainly enough time.

I'm sorry I didn't realize the point of making a starter was to increase yeast cell count to something below the maximum in the volume they occupy. I guess if you don't want or need the maximum cells you can get in your starter volume then sure, go for 15 hours.

 

[kh54s10]

Yes way. 15-18 hours is minimal but the growth will happen. With a stir plate it's certainly enough time.

I saw a video by Wyeast that states 12-18 hours is all that is needed when making a starter using a stir plate. I would trust them!

 

[mightynintendo]

Not good advice. The starter should not be allowed to sit out more than 36 hours.

Why not?

 

[mightynintendo]

I saw a video by Wyeast that states 12-18 hours is all that is needed when making a starter using a stir plate. I would trust them!

I wouldn't doubt it either. I seem to be receiving information from wyeast and the forums that say 12-18 hours is OK and information from actual microbiologists who say 24 hours is best.

 

[jetmac]

I wouldn't doubt it either. I seem to be receiving information from wyeast and the forums that say 12-18 hours is OK and information from actual microbiologists who say 24 hours is best.

Yes, i agree. 24 hours is best.

 

[jetmac]

Why not?

After 24 hours the yeast is pretty much done growing and your are just beating them up, over oxygenating causing off-flavors and using up their energy.

 

[mightynintendo]

After 24 hours the yeast is pretty much done growing and your are just beating them up, over oxygenating causing off-flavors and using up their energy.

I get that when using healthy yeast. If the OP pitched extremely low yeast cell counts or had relatively unhealthy yeast, trying to grow them for a little longer is the only way I can think to salvage the yeast. I agree with your statement for healthy yeast in normal situations. I just don't think this is such a situation.

 

[jetmac]

He could also start with a 1 liter starter, let the cell count grow to whatever, make another 1 liter starter with 100 mL of the starter #1 and 900 mL of fresh wort and let the cell count grow to whatever, then make another 1 liter starter with 100 mL of starter #2 and 900 mL fresh wort, let it grow to whatever, all the while refrigerating and decanting the starters. Eventually he will have his cell count and all of it could be done in 1 liter starters. in fact i know some people who do a lot of research with yeast and this is the method they use to grow yeast cells. not necessarily 1 liter starters, but 1:10 old starter to fresh wort, 24 hours exactly on the stir plate, and repeat until cell count is reached. i think in 1 liter starter, each 24 hour growth phase will produce something like 80 - 90 billion cells.

This is common knowledge but it sounded like the OP was in a hurry, so I assumed taking the time to step up his starter wasn't something he wanted to do. But a 1L starter will not grow enough for a 1.080 beer without stepping up. Which is why I recommended a minimum of 1.5L over the .5L he was using.

I'm sorry I didn't realize the point of making a starter was to increase yeast cell count to something below the maximum in the volume they occupy. I guess if you don't want or need the maximum cells you can get in your starter volume then sure, go for 15 hours.

Apology accepted.

Guess it depends on how much time you have. IMO a minimum of 15hours is way better than no starter. If you have less than 15 hours, I suggest 2 packs.

 

[jetmac]

I get that when using healthy yeast. If the OP pitched extremely low yeast cell counts or had relatively unhealthy yeast, trying to grow them for a little longer is the only way I can think to salvage the yeast. I agree with your statement for healthy yeast in normal situations. I just don't think this is such a situation.

You may be right. And, he may not even be shaking or using a stir plate.

 

[losman26]

Well, I brewed my Pliny the Elder Clone yesterday using the 2.5 L starter. It took a mere 4 hours to show very active fermentation and a good sized Krausen had aldready formed. This is the quickest I've ever seen fermentation take off. I will be buying a stir-plate here soon as well.
Thanks for all your help here!

 

[gcdowd]

I know this is an old thread but out of curiosity, how big a starter can you make with only one vial of white labs without having to step it up?

 

[reinstone]

I made 3 different starters for a large brew. Same type yeast. Same wort. Half gallon starters. All going good. Made them last night. They all smell the same but appear different. Krausen etc. Is this a problem. Thanks