Yeast starter size?

[jmyers04]

I am preparing to brew a NEIPA. I am using Omegas new farmhouse's IPA blend yeast. Says it has 150 billion cells. Date on the package is 04-09-2018. On the calculator I have accounted for the date of the package. I have looked up different yeast starter calculators and have been getting different results. I was wondering if this sounds right to you guys. Here is a run down of my recipe and what the brewer's friend calculator says:

10 lbs pale 2 row
2 lbs white wheat
1.5 lbs flaked oats
10 oz Honey Malt

I will target 5.25 gallons in my fermenter. I brew BIAB. I plan on mashing at 154. Est OG is 1.075. The package says no starter is needed if OG is 1.060 or below so I am making a starter. I have a 2000ml flask. Does the starter I am about to say seem like it would be ok? Brewers friend says target pitch rate for cells is 271 billion. With a starter gravity of 1.036 and a 1.5 L starter and just shaking the flask, NO stir plate....this will get me 302 billion cells....so I should be good to go right? Note-this is my first time making a starter so this is all new to me.

 

[jmyers04]

For example on the different results.....brewunited's calculator with all the same info....says a 1.5L starter will only get me 221 billion cells and still says I need 271 billion cells with simple agitation. So I am confused.

 

[troglodytes]

I think the assumption on most calculator websites is that you are starting with a 100B cells from a fresh vial. With your package date of 4-9-18 that means you would have 89B cells still living. However, if Omega actually starts off with 150B cells, than your starting count is actually 133B cells. With that as a starting point I would expect an 1.5L agitated starter to bring you up to mid to high 200B range. Brewersfriend calculates 279B cells, so that would be right on target. I think you may have forgotten to click update the first time you rant the numbers on brewersfriend and it automatically gave you the cell count with a stir plate, which is why you originally saw 302B cells.

At the end of the day, with a 1.5L starter and fresh yeast, you shouldn't have any problems. I have found that as long as you pitch really healthy and already active yeast, even a small underpitch is not a detriment in any way. Most recently I brewed a 1.062 IPA and only pitched, by my estimate, 150-175B cells but they were at high krausen in the starter. The beer finished with an attenuation 3% higher than Wyeast's quoted range for the strain with no off flavors at all, and all this in only 4 days. Don't sweat the small stuff, as long as you have a reasonable cell count, make sure they are happy and active, and oxygenate, you'll be all set.