First Yeast Starter - Underpitching?

Doing my first yeast starter with a stir plate tonight for a Saturday batch. Using Yeast Bay Vermont Ale liquid yeast. OG is 1.070, 5 gallon batch, yeast has 80 billion initial cell count, produced March 17 (best before July 17). I have a 2000ml flask.

According to Mr. Malty I need 241 billion cells with a 2.14 litre starter and one vial of yeast.

I am assuming that I am using Mr. Malty correctly, and I am wondering how big of a starter should go in my flask. Going to 2000ml leaves very little room. Also what are the effects of under pitching say if I did a 1.5 litre starter? When you do a starter do you make a bit more wort at the beginning to account for the boil (doing a 10 minute boil of water and DME first)?

Any insight very much appreciated.

Your starter should have a OG of about 1.040

Here is what I would do:

day one pitch yeast into 1 quart (approx 1 litre) starter wort with about 3.5 oz of light dry extract.
Let go 24 hours
Place in fridge for 24 hours to settle yeast.
After settling decant liquid out of flask (pour out liquid above settled yeast)
Pitch another quart of wort (about 3.5 oz of DME)
Let go 24 hours
Set in fridge 24 hours and decant liquid off top and you are ready to pitch

So looking at 4 days ...if you do not decant... your starter will be done in 2 days......if you only decant after first day then starter ready in 3 days....

Under-pitching can lead to slow or incomplete fermentation and off flavors

You can realistically do 1.8L (2 quarts) in a 2L flask on a plate. That's going to get you pretty close to the target. I'd roll with that with a thorough aeration/oxygenation of the wort before pitching.

My starter wort is 1.035.

mgortel said:

Your starter should have a OG of about 1.040

Here is what I would do:

day one pitch yeast into 1 quart (approx 1 litre) starter wort with about 3.5 oz of light dry extract.
Let go 24 hours
Place in fridge for 24 hours to settle yeast.
After settling decant liquid out of flask (pour out liquid above settled yeast)
Pitch another quart of wort (about 3.5 oz of DME)
Let go 24 hours
Set in fridge 24 hours and decant liquid off top and you are ready to pitch

So looking at 4 days ...if you do not decant... your starter will be done in 2 days......if you only decant after first day then starter ready in 3 days....

Under-pitching can lead to slow or incomplete fermentation and off flavors

Click to expand...

Thanks for the feedback. Do you always do a two step starter, or just if you are concerned about under pitching?

BigFloyd said:

You can realistically do 1.8L (2 quarts) in a 2L flask on a plate. That's going to get you pretty close to the target. I'd roll with that with a thorough aeration/oxygenation of the wort before pitching.

My starter wort is 1.035.

Click to expand...

Thanks for your feedback. I ended up boiling 1.7 litres and after 10 minute boil and cooling was left with just a touch under 1.5 litres. Once cooled I pitched and it is on the stir plate now. Good to know that 1.8 litres will be fine in a 2 litre flask (for next time I guess). The process went smoothly and aside from the possible under pitching potential I am happy with it. This first starter is actually for my first all grain on Saturday, so it is a bunch of firsts, which I hope go smoothly all in all.

Stupid question, when you said aeration/oxygenation of the wort before pitching you mean my actual wort that I'll pitch my starter into and not oxygenating the starter itself. I will be oxygenating my 5 gallons of wort before I pitch the starter.

Don't think I'll sweat this one too much in terms of cell count as I think I'll be closish....

BigFloyd said:

You can realistically do 1.8L (2 quarts) in a 2L flask on a plate. That's going to get you pretty close to the target. I'd roll with that with a thorough aeration/oxygenation of the wort before pitching.

My starter wort is 1.035.

Click to expand...

I've gotten krausen bubbling out the top of my flask at that level a couple times before. If you have any, a couple drops of fermcap will help keep it under control.

Thanks for the feedback. Do you always do a two step starter, or just if you are concerned about under pitching?

Click to expand...

Always several ways to do things....I myself would do a 2-step on a starter that size for a 1.070 beer....just because it is such a large starter.....but that's because I don't have a stir plate.....most beers I do a single step starter because I don't need as large of a starter because most of my beers are not as high on OG......

Usually do starters in stages of 1 litre (1 quart).....per day....

Just depends on your setup, timing, etc.......don't sweat it too much.....you will be good,.....first liquid yeast beer I did without a starter because I didnt know any better....it was fine

MannyZ said:

I've gotten krausen bubbling out the top of my flask at that level a couple times before. If you have any, a couple drops of fermcap will help keep it under control.

Click to expand...

I do have fermcap but think (I hope) will be good on this one. Already thinking maybe a bigger flask might be handy for when needed.

mgortel said:

Always several ways to do things....I myself would do a 2-step on a starter that size for a 1.070 beer....just because it is such a large starter.....but that's because I don't have a stir plate.....most beers I do a single step starter because I don't need as large of a starter because most of my beers are not as high on OG......

Usually do starters in stages of 1 litre (1 quart).....per day....

Just depends on your setup, timing, etc.......don't sweat it too much.....you will be good,.....first liquid yeast beer I did without a starter because I didnt know any better....it was fine

Click to expand...

Thanks! Appreciate all the input. I did the same ratio of water to DME (10:1) as you. Glad I did my homework as I saw 4:1 and 8:1, but I found on here that 10:1 was fairly common.

Jay-Brew said:

Stupid question, when you said aeration/oxygenation of the wort before pitching you mean my actual wort that I'll pitch my starter into and not oxygenating the starter itself. I will be oxygenating my 5 gallons of wort before I pitch the starter.

Don't think I'll sweat this one too much in terms of cell count as I think I'll be closish....

Click to expand...

I was thinking of the big bucket 'o wort you'd be pitching the starter into, but you should certainly oxygenate/aerate starter wort too. Unlike fermentation for alcohol production, yeast reproduction is an aerobic process (which is why using a stir plate increases the cell count so much). It helps quite a bit if you have a good level of dissolved O2 in the starter wort to begin with.

If I'm too lazy to break out my O2 tank and 0.5 micron stone, I'll take one of my quart jars of canned starter wort (I make several at a time with a pressure cooker), dump it into a sanitized 2qt mason jar and shake the heck out of it before pouring it into the 2L flask.

Thanks, BigFloyd. I shook it around in the flask a bit, but probably not enough. This is good to know for the next one, and I'll definitely pay more attention to aerate/oxygenate the next starter.

It's been on the plate for roughly 10 hours now and has about 1/2 inch of krausen on top. I will leave it until tonight when 24 hours is up and then throw it in the fridge.

Did you brew it today? How did it go?

mgortel said:

Did you brew it today? How did it go?

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Thanks for asking! It was an utter failure. The ridiculous part was that I didn't even get to the mash. So while the beer, which has yet to be brewed, wasn't a failure, the day was a failure because by this point I anticipated being done the batch. Basically what happened is the mill I have was being a total pain in the a$$ and the roller wouldn't stay in place on one side. I'll spare you the ridiculous details, but I eventually came up with a way to do it to keep the roller in place, which involved a pair of vice grips and a rather uncomfortable position when crushing the grain! While far from ideal, I at least have my grains crushed now and ready to go.

I had a lot of prep to do first with various things equipment wise and what not, so I at least got that all done. I am now good to go for tomorrow. I am sure there will be some glitches, but that is all part of learning and getting your process down.

As for the starter, that went very well. Had it on the stir plate for about 25 hours and threw it in the fridge last night, so it will be ready to go tomorrow.

Anyway, long answer to your question and thanks again for asking.

Hopefully tomorrow goes much better.