yeast starter questions

[Redtab78]

I have a question regarding starters, I know the proportionate amounts are around 2 cups of water and 1/2 cup DME, but how do I get that up to 2L? Do I keep adding 2 more cups and 1/2cup DME till Im at 2L? wouldn't that put my gravity way beyond the 1.040 to start?

Second question is concerning steps on stir plates. If I make a 2L starter and have it on stir plate, how long should I let it go before cold crashing it, and then do I mix more DME and water, and after decanting the cold crashed yeast, refill it with the new wort to bring it back to 2L?

I hope I don't sound confusing here, but I will be making a Mac and Jacks clone next weekend and a 2L starter is recommended on the calculator I used and I just want to make sure I am doing it right, thanks!

 

[porterpounder]

If you keep the ratio 2 cups water: 1/2 cup of DME then the gravity increase is linear. It won't increase the overall gravity of the solution. So for 2L (about 8 cups), it's about 2 cups of DME. Just added the package of yeast you have to the whole 2L starter, let it go at about 65-70 F for 36-72 hours, decant and pitch. You can step up with a smaller amount of starter wort if you have a smaller than usual initial pitch, but it isn't necessary otherwise. Check out some of the online yeast calculators to make sure you are starting with enough yeast.

 

[brew_darrymore]

There is an easy rule for starters: water to DME ratio is 10 to 1.

So, for a 2000ml starter, you should add 200 grams (not ml) of DME. Don't go by volume, but by weight when measuring DME.

 

[m00ps]

the rule of thumb is 1g DME per 10ml water. So 200g DME for 2L of water. If its asks for a 2L starter, you dont need to crash, decant, and refill wiht fresh wort. That is only for trying to get a cell count higher than the size of your flask would normally allow

 

[Redtab78]

If you keep the ratio 2 cups water: 1/2 cup of DME then the gravity increase is linear. It won't increase the overall gravity of the solution. So for 2L (about 8 cups), it's about 2 cups of DME. Just added the package of yeast you have to the whole 2L starter, let it go at about 65-70 F for 36-72 hours, decant and pitch. You can step up with a smaller amount of starter wort if you have a smaller than usual initial pitch, but it isn't necessary otherwise. Check out some of the online yeast calculators to make sure you are starting with enough yeast.

According to the calculator I used I should have enough (just a tad over) what I need in cell count, but I figured I would ask the question now so in the future I have a better understanding of the step up procedure, thanks!