Yeast Starter Ratios really important?

[Screech]

I have just been reading up on making yeast starters and I just don't understand why water/malt extract/yeast ratio is so important. It seems to me as though as long as the yeast are multiplying then you accomplished your overall goal. Is there more to this, or am I dumbing this issue down?

I am about to begin a yeast starter tonight and all I have is LME. I used mr. malty and it told me I need 1.93 liters of starter with intermittent shaking. What is this 1.93 liters? Is it water, or the extract mixed together with it? I am brewing a Victory Hop Devil IPA clone with expected OG: 1.069 and expected FG: 1.018.

Sorry for all the questions, it just seems to me like the ratio is not important. Please correct and/or help me.

Kevin

 

[homebrewdad]

The ratio is important in that if you make a starter with too much extract in too little water, you get a high gravity starter. This causes yeast to have to work harder in order to ferment your starter at the expense of reproduction - which is the entire point of a starter.

You ideally want an OG of about 1.040.

Good news - the ratio is stupidly simple to manage. A half cup of DME boiled in two cups of water gives you a 1/2 liter starter of ~ 1.040 OG. Double that for a 1 liter of the same OG.

If you need a 1.93 liter starter, I'd personally just do a full 2 liters and be done with it. You may need to do a 1 liter, then step it up once the yeast do their thing the first time.

 

[Hex23]

Read the article on Mr Malty for why a wort between 1.030 and 1.040 is important. It will do better justice than I can explaining why, but it is important. 1.93 is the final volume after DME is added.

 

[shawnbou]

The ratio is important in that if you make a starter with too much extract in too little water, you get a high gravity starter. This causes yeast to have to work harder in order to ferment your starter at the expense of reproduction - which is the entire point of a starter.

You ideally want an OG of about 1.040.

Good news - the ratio is stupidly simple to manage. A half cup of DME boiled in two cups of water gives you a 1/2 liter starter of ~ 1.040 OG. Double that for a 1 liter of the same OG.

If you need a 1.93 liter starter, I'd personally just do a full 2 liters and be done with it.

+1 to all of the above: the technique and the reasoning behind it.

The one thing I would say differently is that I have done many 2 liter starters in the past by just pitching the vial into the full starter volume, rather than stepping up. I've never had a problem, and in fact it's so easy, I now rarely do any starter smaller than 2 liters.

 

[Screech]

I appreciate all the help guys. I just finished making the starter and used the 2 liters of water and roughly 2 cups of LME. I boiled it, cooled it, then pitched the vial of yeast. I will brew my third batch of beer tomorrow. I get alittle more technical, and hopefully closer to brewing the correct way, with each batch. The last batch I made a starter, but just kind of eyeballed everything. The OG and FG were very close to the expected, but I haven't tried it yet. Hopefully this batch will be even better.

I'm reading the article in Mr. Malty and if anyone is interested here is the link: http://www.mrmalty.com/pitching.php

Brewing beer is a learning process.

Kevin

 

[dutchoven]

I use the Mr. Malty recommendations ... My starters are usually 100-150g LME/1000-1500mL water ... From what I've read, you want the yeast to focus on building reserves in the starter so they can go at the wort quickly ...

 

[TyTanium]

This website is a great resource too: http://yeastcalc.com/

 

[homebrewdad]

I may try a bigger starter myself, next time.

That being said - starters are your friends!

They are so easy to do, and you don't need a fancy flask to make one. Don't make me post my "plastic tea jug" starter pic again...

 

[Hex23]

I'm reading the article in Mr. Malty and if anyone is interested here is the link: http://www.mrmalty.com/pitching.php

Don't miss this one either. http://www.mrmalty.com/starter_faq.php

If you're interested in learning more about yeast I'd highly recommend "Yeast: The Practical Guide to Beer Fermentation" - AKA "The Yeast Book" http://www.mrmalty.com/books.php

It includes the content of those articles and a little more detail about starters and of course more than you might ever want to know about yeast as a home brewer.

 

[helibrewer]

There is a great table in the book YEAST which shows just how important the ratio of yeast cells to starter volume is also.

One vial in a 2L starter has almost twice the growth factor (cell multiplication) than one vial in 1L.

As you step up you want to try to keep the cell count at around 50 million cells per mL, so a 1L starter should be stepped up to a 4L or split into (2) 2L. A 2L should be stepped up to an 8L to have the same growth factor.

 

[jetmac]

I appreciate all the help guys. I just finished making the starter and used the 2 liters of water and roughly 2 cups of LME. Kevin

I think that's way too much LME. I've never used LME.

For DME you should be using a 10:1 ratio. So for a 2L starter(2000ML) you should use 200ML of DME which is about 6.76oz.

 

[Screech]

I was actually just thinking back now and I used 1 cup instead of the 2 cups like I said. I used 2 half cups of LME to the 2 liters of water, so hopefully I will be fine. I also read that you should use roughly 20-25% more LME if you are using this instead of DME. I guess this is because it already contains water so the concentration is not as great as the DME.

Kevin

 

[jetmac]

I was actually just thinking back now and I used 1 cup instead of the 2 cups like I said. I used 2 half cups of LME to the 2 liters of water, so hopefully I will be fine. I also read that you should use roughly 20-25% more LME if you are using this instead of DME. I guess this is because it already contains water so the concentration is not as great as the DME.

Kevin

Just remember, whatever you use, as a general rule, you want the gravity 1.030-1.040. The goal is to grow yeast in the starter not make beer. So you want them to grow but not work hard.

 

[Screech]

So I have an update. Apparently the yeast starter did its job because I went to the basement this morning to check on it and the blow off tube had blasted off. There was crap all over the ceiling and floor. I am using a 1/2" ID tube and part of the airlock for my blow off. I guess it got clogged up with crap and built up too much pressure. I'm going to look into a blow off tube that fits the ID of the carboy instead. Hopefully nothing is contaminated. I guess I'll find out in a couple of weeks.

Kevin

 

[OvaTersley]

There is a great table in the book YEAST which shows just how important the ratio of yeast cells to starter volume is also.

One vial in a 2L starter has almost twice the growth factor (cell multiplication) than one vial in 1L.

As you step up you want to try to keep the cell count at around 50 million cells per mL, so a 1L starter should be stepped up to a 4L or split into (2) 2L. A 2L should be stepped up to an 8L to have the same growth factor.

Just curious, why do you want to keep the cell count at around 50 millions cells per ml?

 

[Golddiggie]

Use DME not LME for starters with a ratio of 1L water to 100G of DME (the proper 10:1 ratio). If you use LME, you'll need to use more to get to the same OG.

I typically make either 2L or 3L starters, in a flask, on a stirplate. I also use a foam stopper to promote proper gas exchange. You don't want to just vent CO2, you also want to pull in oxygen to keep the yeast growing/reproducing.

If you're not sure of the ratio and such, get a refractometer (Bobby_M sells a great one for cheap money) and use that to get a quick read on it. Still the DME:water ratio above works withput fail. Most decent (or better) digital scales will let you measure in ounces as well as grams. Far better than trying ro use measuring cups IME.

Also, with a stirplate, the starter will finish in about 24 hours. Use fermcap-s and you won't need to worry about blowoff.

 

[petey_c]

I may try a bigger starter myself, next time.

That being said - starters are your friends!

They are so easy to do, and you don't need a fancy flask to make one. Don't make me post my "plastic tea jug" starter pic again...

I just pitched a starter l made yesterday morning. I pitched at 11 and it's bubbling away as I type (keyboard?). 1.5-ish cups of DME to 6 cups of water. It sat on the stirrer until this morning. I was too impatient to take the FG.
I use a plastic tea jug (pitcher) as my flask. I didn't want to spend the money/wait to buy a Erlenmeyer flask. I tried a few different containers as flasks and settled on the jug because of the flatter bottom. It works good and the lid has a strainer to keep the stir bar from being pitched as well.

 

[homebrewdad]

I just pitched a starter l made yesterday morning. I pitched at 11 and it's bubbling away as I type (keyboard?). 1.5-ish cups of DME to 6 cups of water. It sat on the stirrer until this morning. I was too impatient to take the FG.
I use a plastic tea jug (pitcher) as my flask. I didn't want to spend the money/wait to buy a Erlenmeyer flask. I tried a few different containers as flasks and settled on the jug because of the flatter bottom. It works good and the lid has a strainer to keep the stir bar from being pitched as well.

Heh, I won't post my tea jug pic again, but these have worked GREAT for me so far.

 

[helibrewer]

Just curious, why do you want to keep the cell count at around 50 millions cells per ml?

That cell count allows the yeast to a little more than double in population....if it's more concentrated than that, the yeast growth rate is reduced. You can certainly go more dilute (even better growth) but you start to get pretty big starters in a hurry (8L+)

 

[spokaniac]

They are so easy to do, and you don't need a fancy flask to make one. Don't make me post my "plastic tea jug" starter pic again...

I use a clear 2 liter bottle and make 1.5 liter starters. I like the fact that the krausen mimics the start pattern on the bottom as it starts to form.