Starter gravity

[Moboy]

How close should the gravity of your yeast starter be to the gravity of your wort? I am brewing an imperial stout and the OG will be about 1.089. Also, I have read that for every gravity increase of .008 above 1.048, you should double your pitching amount. I am not sure how many yeast cells will be in my starter after 12 hours so I am thinking about just pitching 4 tubes of White Labs yeast. Any suggestions or insight would be appreciated.

[YamahaXS]

I have never heard of doubling your pitch, but if I had to guess the reason behind pitching extra yeast would be to ensure that yeast has a headstart over possible bacteria, hence extra yeast for wort with a lot of food.

The end result is the same regardless of how much yeast you pitch. Yeast will multiply until their food runs out, or until the alcohol level in the beer kills them (something you probably don't have to worry about as 1.o89 isn't extraordinarily high (ie you will get a 7-8% alcohol beer). You might have to wait a little longer for fermentation to bloom, settle down, and finish if you pitch less yeast, but I doubt that it would be significant.

I would also guess that your starter gravity is immaterial assuming that there is enough sugars to let the yeast grow and that you pitch it while it is still active.

Yeast is expensive. I am cheap. I say don't pitch any extra yeast, rather just make sure your equipment is clean.

just my 2 cents.

[Tweek]

If you are making a starter there is really no need to pitch multiple vials. Well for that matter even if you werent the gravity of that beer is not high enough to warrant multiple pitches. Make a 2 pint starter per 5 gallons. I brew 10 gallons at a time and I just make a 4 pint starter and pour half into each carboy (hardly the scientific route) and my ferments typically start kicking over in just a few hours. 12 hours is a bit short but the results will be fine you will just get a bit more lag time.

hope that helps

[paul84043]

You may be worrying too much...
The only thing you should verify is yeast viability before pitching, as long as you're using the good liquid yeast, the standard tube they give you with your kit is plenty!
If you are using the Wyeast foil pack, you verify viability by making sure that the pack swells within the alloted amount of time. The one I used was near bursting after only 3 hours, so I knew the yeast was going to town.
With the white labs tubes, you have no visible signs of viability, but as long as it's sat for a minimum of 3 to 4 hours at room temp, when you open it it will act like a can of pop, so have the bottle (the top at least, pre sanitized and sanitize your hands because it's going to get all over, and you don't want to waste any.

The dry packs, I would definitely make a starter. For batches larger than 5 gallon and for very high gravity beers, like Barleywine, I would also make a starter. (your indicated gravity is decent, but not really high) Otherwise, no worries!
I have been using the oxygen and I typically see significant activity within 8 hours of pitching. Usually, I will make a batch in the evening, and by the next morning, my airlock will be going at 20 to 40 seconds per bubble.
With the cost of the White labs yeast, I would definitely not picth multiple vials!