Starter and yeast growth question

I’m making a lager with a OG of 1.049. Mr. Malty says I need 361B cell count. How do u figure growth rate. I only have one pack of Wyeast 2124. I will need 3 guarts of starter . What I don’t know is how much DME I need and should that be boiled with the 3 qt of water. I’m really trying to understand this whole starter thing. I need some simplified information. I’ve read mr malty and lots of other articles on this

284 grams DME for a 3qt starter will provide a gravity of ~1.035.

To quote Jamil…

As a ballpark measurement, use about 6 ounces (by weight) of DME to 2 quarts of water. If you’re working in metric, it couldn’t be easier. Use a 10 to 1 ratio. Add 1 gram of DME for every 10 ml of final volume. (If you’re making a 2 liter starter, add water to 200 grams of DME until you have 2 liters total.) Add 1/4 teaspoon of yeast nutrient, boil 15 minutes, cool, and add yeast.

Some other useful starter information can be found in the article from which the above quote is taken.

http://www.mrmalty.com/starter_faq.php

Or about 10oz.

In other words, buy a nice kitchen scale. One that is in Oz and Grams. Will run $30-$50 at any of the big box stores. I use mine in the kitchen 3-4 times a week of non brewing things. Portion control for snacks mostly.

Yes you should boil this. Doesn’t take much. 3-5 minutes is fine.

Growth rate is comparing the number of cells that you start with (100 billion) to the target number of cells (361 billion). You would have to use a high growth factor because you need each yeast cell to replicate 3-4 times. If you were to pitch two packs of yeast (200 billion cells), they would have to replicate half as much as with one pack of yeast, and then you could use a lower growth factor.

J

I only have 1 yeast pack. How do I get to 361B. Or close. Do I still use 6 oz DME to 3 qt of water?

http://www.mrmalty.com is recommending 2 packs of yeast in a 3.11L starter for a 5.25 gallon bartch of 1.049 lager.

You can use yeastcalc.com to plan “stepped” starters. Acccording to yeastcalc, first do a 2.5L starter. After the yeast has flocullated, pour off the liquid and then do another 2.5L starter. If you shake it up intermittently you will get even more yeast.

I use 3 oz (by weight) of light DME per quart. And a pinch of yeast nutrient.

3qt water + 6oz DME will get you enough to pitch.

You can ferment your starter at room temp. Once finished, keep it in the fridge for 2-3 days. Come brewday, pour off the liquid and pitch just the cake.

If you have 2, 1 gallon jugs, make two 3qt starters. Pitch the yeast in one jug. Pour 1/2 in the other jug. Then top both off with more wort. Shake as often as you can.

Or as mvsawyer, go with what you have. Your beer will be the best you have made.

Relax… :cheers:

3qt water + 6oz DME will get you enough to pitch.

You can ferment your starter at room temp. Once finished, keep it in the fridge for 2-3 days. Come brewday, pour off the liquid and pitch just the cake.[/quote]
A single 3qt starter won’t grow enough yeast for a lager, you’ll need 6-7L or do a stepped starter.
And 2 oz DME/qt will grow even less.
+1 on growing the yeast at room temperature.

Not sure what I did there…
From Mr.Malty and Yeastcalc, you can grow 350B from 100B with a 4qt starter and 12oz DME. Unless there is something else about large starters and 1 smack pack I don’t know about.

Sorry I f’d that first one up.

With “intermittent shaking”.

Boy u guys really get into this whole starter thing. Well I just ordered a second smack pack and ill put off brew day till I can make the right size starter. If u guys can’t tell I’m just getting into starters. I been using safale 23 as a lager yeast and the others have been ales. I’m ready to take beer to the next level. Thanks for all the help, I really do know how important a starter is

361 billion is for 5.25 gallons of wort (the default volume on Mr Malty). I like http://yeastcalc.com better; same info just a little easier to play with the variables. Plus it gives you a DME calculator on the left side to figure out how much to use once you know the starter volume you are going to use. If you drop the volume to 5 gallons and use the “intermittent shaking” numbers you can get to about 345 billion with a 3.8 liter starter. That’s pretty big, but if you have a big enough jug, go for it. The “growth factor” is influenced by your technique of aeration. The calculator allows for none, O2 injection, intermittent shaking and a stir plate. Play with the calculator and you’ll see how they infuence the final cell count of a starter of any given volume. Basically the more you aerate and stir your starter, the more yeast you end up with. The best ratio of starter to final cell count comes from a stir plate. For example, you could get the same cell count I mentioned above with just a 2.5 liter starter. With no stir plate and 3.8 liters being too big, you can do a “stepped” starter. Basically you just do the whole process twice. Using this technique you could do a 1.5 liter starter twice. There’s really no need for two yeast packs; you can always grow enough yeast with some DME, know how and patience. I highly reccomend a stir plate and enrlenmyer flask (beaker). The stir plate really ramps up the cell count allowing smaller starters, and the flasks are great because you can boil the starter wort right in the flask, put it straight into an ice water bath to cool, and then pitch your yeast. No pouring necessary! Search the web for stir plates if price is an issue, I’ve found them as low as $40. And get at least a 3 liter flask; 1 is almost useless, and 2 is smallish for most starters. I have a 3 liter and it’s even a bit small sometimes…

I check yeast calc. Its telling me i can use 8.5 oz DME, 2.5 qt , OG 1.038 using a stir plate which i have , I can get to the 350B yeast count that im trying to get at with only 1 smack pack. IS THIS CORRECT?

Yep.

Didn’t know that you had a stirplate. How big is your flask?

You got it! There’s a lot of misconception out there about the purpose of starters. “Yeast” is a great book by Cris White and Jamil Zainisheff that I highly reccomend. Just remember, it may be nice to pitch actively fermneting yeast but the main purpose of a starter is to pitch the correct number of cells to get the job done with the best flavor results possible. Pitching too few or too many yeast cells can negatively impact the end result. Enjoy!!

I have a 3 liter flask. I just never got into the starter part of brewing so im cutting my teeth now. Im not in to high gravity beers nor hoppy style beers. Theres also not another homebrewer around here for miles so im on my own.

3 liter flask is plenty even for some lager yeast starters if you have a stir plate. If not, it’s certainly plenty for all but the biggest ale. Try to get close to the yeast calculator numbers, practice good sanitation and temperature control. Do all that and your beer will be great. I just moved a year ago to a non-homebrewer area and I already have 2 neighbors getting into it. If you brew it they will come!!! :cheers:

I just made another starter and its in the frig. Long story short i cant brew till next weekend. will it be ok in the flask in the frig till next weekend?