Using the same yeast for two brews, is this starter yeast procedure ok?

[geeyoupee]

Ok, so I'm making two brews with the same yeast. I wanted to make a bigger start yeast than needed so that I could have some extra yeast to put in the fridge for the next batch.

According to mymalty, I need 1 liter of starter yeast. My plans were to make 1.5 liters of starter yeast to save .5 liter.
Steps
1: 1.5liter of boiled water + 150g LME + yeast from smack pack after wort is cooled.
2: let it ferment for at least 12 hrs (not really sure how long to ferment for)
3: Stir the starer to suspend the yeast and pitch 1 liter into wort.
4: Put the rest of the starter in the fridge and save for next brew which I will make another starter.

Questions I had
1: Does the saved starter needed to be decanted after the yeast have settled and how long will it last for in the fridge?
2: How long should I let it ferment for? Some say 12 hrs and I've seen some say up to a few days.
3: Is pitching the yeast + the starter beer into the wort a good idea or should I fridge it to get rid of the beer first. I read that putting it in the fridge and decanting will put the yeast in dormancy. Does dormant yeast require anything else before pitching?
4: If I were to fridge the starter and decant it, how would I split the yeast up to save it for another batch? Could I just add 1.5 lit of sterilized water to the yeast cake and pitch 1liter of it?

I wanted to use the same yeast for two batches of similar beer but I didn't want to reuse yeast from a old brew. I'm afraid the yeast would be stressed or contaminated. I haven't read anything about making extra starter yeast and saving it for another batch so I wasn't sure if it was a good idea.

Thanks in advance, any other suggestions?

 

[FarmBoy530]

I think you it would be less work and more productive to rinse and store yeast out of the primary. Jamil said something about not needing a starter if you pitch within 2 weeks of rinsing. Its hard to do this without knowing the cell count your pitching, but I'm sure I over pitch sometimes. I just use a good portion of clean whit yeast after its been rinsed really well. Its not everyone's method but it works well for me! ferments faster and harder the 2-3rd time too.

 

[william_shakes_beer]

Are you planning to do 2 brews the same day or is the second one being brewed after the first is fermented out and in the bottles? If the latter, I'd save a sample of the first starter into a sanatized jar and use that to make a starter for the second batch. To answer your first question, I put my starters on a stir plate and put them in the frige after the krausen has fallen. Then on brew day I take the starter out to warm on the counter to room temps, and decant the starter beer off just before I pitch the slurry.

 

[geeyoupee]

@Farmboy. I want to use yeast that hasn't fermented a whole batch of beer. I think it will be more consistent this way. I will save the yeast cake in case though.

@William. I was planning to brew the 2nd brew like 2 weeks later. The first brew only takes about 3 weeks to ferment, no secondary. The 2nd brew takes about 4 weeks with a secondary. This way the first brew will be in bottles and free up the bucket to be used as a secondary for the 2nd brew. I will try to get the second brew racked when its still fermenting and creating co2 to displace the o2 in the bucket.

How long do you think the saved starter will last in the fridge?
How long does it typically take for the krausen to fall back?
Is there a reason why you decant after it warms up and not before?

I'm planning to ferment in my hometown so I'll be back for the weekend. I was thinking of trying to create a starter and skipping the fridge step because I'm on a tight schedule. Plus I read some comments saying that active fermenting yeast is better than cold dormant yeast.

 

[Misplaced_Canuck]

If it were me, I'd do it this way:

1) Make a starter for batch of beer. Try to pitch this at high krausen.
2) Save some of the above yeast in the same container. Let it ferment out at room temperature.
3) 2-3 days before brewing again, make some starter wort and add it to the now-dormant starter; it should pick up in 24-36 hours.

MC

 

[FarmBoy530]

Your silly to not want yeast that has been used for a batch of beer. Most brewers and brewery's will tell you the yeast ferments best on the 3rd generation, and the 2nd is better then the first. Plus yeast is so easy to rinse and it wont break your check book with dme for all kinds of starters. I just feel like there are better, cheaper, more productive ways to do what your trying to do.

 

[geeyoupee]

The reason why I want to do this is because I'm a new brewer and want to strive for consistency. If the yeast ferment better or different on different generations, my brews won't be as consistent. My brewing prof did say that yeast can be reused up to six times before they get too old so I'm still thinking if I should just repitch the used yeast. He also said that some brewers will only use yeast once before tossing it.

If I plan to reuse the yeast, will racking to the secondary earlier than normal (to create a co2 bed in the secondary bucket) cause the yeast cake in the fermentation bucket to have very low cell count?

 

[FarmBoy530]

Many brewery's repitch yeast so I'm sure it should work for you just as well. You wont notice a negative difference until you pitch it to many times, maybe stick with 3 generations. You want to leave your beer in primary for a bit after the fg is reached to let the larger amount of yeast work on your off flavors. Your beer will keep some co2 in suspension for some time, this will offgass in your 2ndary even if its been in primary for 2 weeks. don't rack early to try to get a co2 blanket. After you rack you would be saving and rinsing your yeast.

 

[geeyoupee]

Many brewery re-pitch yeast but they also do an acid wash to get rid of any unwanted bacteria. I guess I'm paranoid about unwanted microbes.

I'll take your advice and reuse the washed yeast. Although the people on the reviews for my extract said to keep the beer in the fermenter for 3 weeks then off to bottling. This means that I can't start my second brew for at least 3 weeks.

I guess that was another reason why I wanted to save some yeast to start a new starter.

 

[FarmBoy530]

You can put your beer in a 2ndary as soon as its done fermenting (as little as 2 or 3 days) but I would leave it at leas a week. Then take the trub from the primary. I don't belive brewery's wash they're yeast every time in and acidic wash. Its not good to mess with the yeast if you don't have to. Simple answer is if you are very careful and sanitary you wont introduce microbes. Pre boil all water you use, flame the top of your carboy and boil your containers. You'll be fine, you'll be impressed, and you'll do it again! its easy, fun, and when you see how fast that yeast takes off it will almost make you jump! I love watching an air lock bubble the same night i brewed, before I go to bed! Go to the brewing network and listen to the brewstrong episode on rinsing yeast! GOOD INFO!!!