Starter from slant or colony - cell count question

When looking through Mr. Malty's pitching rate calculator, it was obvious to me it's not designed for making starters from colonies and slants. Makes sense, after all most people rely on commercial yeast.
I'm not one of them. I like to use yeast from my yeast bank. I have put too much time and effort in it to not use smack packs and sachets.
What I am trying to find out is: how many yeast cells do I get from a colony or a slant? Let's say I pick one colony from a plate, how many cells do I have? what volume of wort do I pitch it in, and how many cells do I have then?
If nobody has done it, I will do the experiment myself.

This is what I plan if nobody already knows:

*Picking several colonies and counting the cells in each one by plating a dilution on DME-agar
*washing yeast of a slant and count the cells by plating a dilution
*Pitching one colony in 1, 5 and 10 ml wort and counting the cells after 24 h
*Stepping up to 2x, 5x and 10x the volume, using a stirplate as soon as the volume is big enough
*Compare the yields between the different step factors: measuring yeast volume per volume of starter and count cells per ml yeast sediment

I know, it's a rather big job. But I feel that somebody has to do it, and I would really want to know how many cells I have when making a starter from a colony or slant.

I started a yeast colony on a petri dish a couple years ago but never got around to using it (it's no longer with us RIP) so I don't have personal experience to share, but I did just listen to a basic brewing podcast in which a guy who works with yeast professionally talked about his methods. He would scrape some good yeast into a 200 ml starter. He then mentioned the power of ten rule, in that you should only pitch to wort ten times the size of the current starter, so 2000 ml/ 2 liters...

I don't remember him stating any cell numbers, so what you have planned will be a great experiment to follow!

I'm going to email your question to Wyeast and see if anyone there is kind enough to offer some information. May be then you could just run an experiment to confirm their numbers...

See http://maltosefalcons.com/tech/yeast-propagation-and-maintenance-principles-and-practices

-a.

I sent wyeast an email regarding your questions and they emailed me the phone number for lab services and said that it would be easier to discuss it on the phone. I gave them a call yesterday asked some of the Maarten's questions. The guy I talked to was really nice and wanted to help, but he seemed confused by my questions, as in, this is not something we worry about... From his perspective, the bottom line was that if you build up a starter from a slant gradually (i.e. 6-10 ml to 50 ml to 200 ml to 2 L) and you are using a stir plate, then you should not have to worry about how many yeast are in a single yeast colony on your petri dish or whether you should start out with 6 or 20 ml... He did not have any idea how may yeast would be in the first 10 ml of wort. If you start out with too much wort, you are giving bacteria a chance to take off before the yeast can get a foothold. I asked if there were any way to know on average how many yeast would be in a ml of wort, and after thinking about it he said that if you use a stir plate there should be around 1 x 10^8 with the 200 ml starter and higher. So at this point you just need to figure out how many yeast you want for your gravity and batch size.

I hope this does not discourage the original poster from carrying out his experiments -- It would be really interesting to see the results and it doesn't sound like anyone has investigated it! I was hoping Wyeast would be able to answer some of his questions, but it seems like it is not something that they worry about.