Author Topic: Repitching yeast?  (Read 2275 times)

Offline tschmidlin

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Re: Repitching yeast?
« Reply #15 on: November 10, 2012, 12:48:53 AM »
Nope. This is how it's actually done if you want to get the accurate cell count from which you can project how much of this slurry you'll need.
True, except that by the time the plates have grown enough that you can count colonies (1 over night and you can see them if you look closely, 2 over nights and you can count, but 3 overnights is easier) the viability of the culture may be different ;D  If you're going to do the plating I would skip staining, that isn't as accurate.

But unless you are into all of that, I would just do what Sean says.
about 120 mL of slurry would be the target
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Offline dimik

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Re: Repitching yeast?
« Reply #16 on: November 10, 2012, 04:52:38 PM »
Yeah well, he wanted a really rigorous approach...
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Offline anje

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Re: Repitching yeast?
« Reply #17 on: November 10, 2012, 10:26:07 PM »
Make sure you change pipette tips every time, too, or your serial dilutions won't be accurate. (Please don't ask how many times I've tried to fudge this and wound up with bad plate counts!)
<-- microbiologist brewster n00b.

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Offline tschmidlin

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Re: Repitching yeast?
« Reply #18 on: November 11, 2012, 01:08:41 AM »
Yeah well, he wanted a really rigorous approach...
True.  :)

Make sure you change pipette tips every time, too, or your serial dilutions won't be accurate. (Please don't ask how many times I've tried to fudge this and wound up with bad plate counts!)
That's also true. ;D
Tom Schmidlin

Offline davidgzach

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Re: Repitching yeast?
« Reply #19 on: November 11, 2012, 06:56:39 AM »
Yeah well, he wanted a really rigorous approach...

I would still rigorously swirl up all three jars and toss them in...... :)
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Offline dimik

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Re: Repitching yeast?
« Reply #20 on: November 11, 2012, 09:21:36 AM »
Yeah well, he wanted a really rigorous approach...

I would still rigorously swirl up all three jars and toss them in...... :)

Hehehehe.

Make sure you change pipette tips every time, too, or your serial dilutions won't be accurate. (Please don't ask how many times I've tried to fudge this and wound up with bad plate counts!)

That's assuming he's using micropipettes :D
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Offline anje

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Re: Repitching yeast?
« Reply #21 on: November 11, 2012, 09:40:45 AM »
Make sure you change pipette tips every time, too, or your serial dilutions won't be accurate. (Please don't ask how many times I've tried to fudge this and wound up with bad plate counts!)

That's assuming he's using micropipettes :D
Yeah, but why dilute into 10 ml when you can dilute into 1? Not to mention, you'd have to have a decent-size set of serological pipettes to do this right, otherwise. 
<-- microbiologist brewster n00b.

Hops and toothpaste don't mix.

Offline ynotbrusum

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Re: Repitching yeast?
« Reply #22 on: November 13, 2012, 05:54:22 AM »
I'm no microbiologist, but I like the sample on the far left.  To be safe, though, I would decant and dump it all in.
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