Yeast Calculations

When I go to the yeast starter section and enter that I am using a 1 L starter size and Beer Smith comes back and says I need 1 yeast pack with starter, it it telling me that I only need 1 yeast pack or 1 yeast pack in addition to the starter?  For this particular brew I needed 222 billion cells and with a starter I would get 237 billion but I am unclear if I need to pitch the starter plus another yeast pack. 

I believe what it is saying that you need the one yeast pack added to the starter and then the starter goes into the fermenter. If you have old yeast that has decayed a lot then BS might call for more packets of yeast to ensure that you have enough yeast for the starter to even do any good. Its all based on the viability of the yeast you are starting with.

Curly55 said:

I believe what it is saying that you need the one yeast pack added to the starter and then the starter goes into the fermenter. If you have old yeast that has decayed a lot then BS might call for more packets of yeast to ensure that you have enough yeast for the starter to even do any good. Its all based on the viability of the yeast you are starting with.

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You are correct. Something I would mention that I found out, as I do most things, the hard way:
I keep my brew recipes at a bogus date (11/11/11) so it doesn't automatically populate the calendar with the beer I'm creating. (the date in the upper right is the date you start your recipe, unless you manually change it). I was adding a yeast, put in the proper yeast bottling date, and it gave me a .84qt starter with one vial of 97% viablility. Weeellll, I didn't change the date to my actual brew date (2 days hence) and I went ahead and created my starter, got it on the stir plate, life is good. Then, I was getting ready to print the brew sheet, and wanted to see when I was going to have to do what on the calendar, and I changed the date to my actual brew date. For whatever reason, I went back and looked at my starter, and BLAM..... suddenly my yeast was only 37% viable, and I needed something like 1.4 qts....YIPES , now, on this beer, it won't make that much of a difference, but it was certainly worth noting in my pea brain that it is important to change the brew date of the recipe to the ACTUAL date so all the calculations are correct.
Just thought I'd share, so someone out there can learn from my ignorance.

Change the date of your yeast in the ingredient profile. That will restore the viability.

I have the calendar populated from the brew log file. I send the base recipe to that file and add proper dates, there. It works pretty cleanly, for me.

Curly55 said:

I believe what it is saying that you need the one yeast pack added to the starter and then the starter goes into the fermenter. If you have old yeast that has decayed a lot then BS might call for more packets of yeast to ensure that you have enough yeast for the starter to even do any good. Its all based on the viability of the yeast you are starting with.

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I've heard that if you pitch 100 billion cells into a starter you can figure on getting 50% growth or 150 billion cells.  So it sounds like BS is telling me to pitch an additional yeast pack along with the starter.  Bottom line, I would need 2 yeast packs to get me to 222 billion cells needed for my brew.  Where can I purchase "BeerSmith 2" for Dummies book?  I guess it will all make sense some day.  Maybe Brad needs to write another book that really explains all the fields of his software. 

donsmitty said:

When I go to the yeast starter section and enter that I am using a 1 L starter size

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How do you do that?  I see no place for you to enter your starter size.  BS2 calculates the starter size needed based on your inputs.

A typical 2 liter starter will double the cell count.  Using a stir place you can often use a 1 liter starter to double the cell count. 

BS2 shows the size of the starter needed based on your inputs and the number of yeast packs to add to that starter.  For 227 billion cells, you would need a 1 liter starter on a stir plate and once vial of yeast packaged today if you have a 5 gallon batch of 1.066 wort.