Going To Yeast Slants

[goatus]

Hi all,

Noob question.. wouldnt a hot flamed loop kill the yeast you are picking up? Do you let it cool first? If so, for how long?

 

[Wolfy]

Yes, that is the idea, the flame will kill everything that is on the loop.
Then once the loop is sterilized, you cool it in wort or in the agar (or even the air) before picking up yeast with it - the loop is only small so it cools very quickly.

 

[Banshee]

Hi all,

Noob question.. wouldnt a hot flamed loop kill the yeast you are picking up? Do you let it cool first? If so, for how long?

I got my loop from a lab. The wire glows red hot and it is cool within seconds. If you are unsure you place the tip on the agar which is free from yeast.

 

[mxd]

thanks all, my next and hopefully last silly q.

When I am going to make a starter I planned on doing the following steps.

1) Wort in Test Tube to fill it up, when good head move to 2)
2) 100-150ml of wort, heated stir plate
3) 1000ml of wort heated stir plate.

Assuming people do this type of step routine (10-15 to 100 to 150 to 1000), do you make 3 batches of wort (15ml, 150ml, 1000ml) or maybe 2 a 200 (split between 15 and 150) and then the 1000 ?
I have seen comments about freezing some wort etc..

I am just not too sure what is the "best" way to go.

thanks
Matt

 

[Fourstar]

I don't scrape a loop of culture off a slant and then re-seal it when I am building up a pitch.. I just fill the whole slant with wort and then discard the slant. So I make 4 or 5 slants of each strain. Use 4 then re-culture. If it so happens that I am unlucky and the 4th doesn't work out... I will just tough it out and get a new smack pack. Hasn't happened yet and I have re-cultured slants that were 18 months old. I usually only leave it 6 months though.

Exactly my procedure and i havnt had any issues with them firing. Alternativly to thristy i make up around 250ml of wort, the 1st 50ml goes into the slant, shaken (not stirred) and activated for 24 hours while the 200ml goes into the fridge sealed. come that time the next day i decant the top 'break free' wort into a sanitised erlenmyer along with a stirbar, the agar wort and yeast. Bung it on the stirplate and she fires up with no problems from there. :icon_cheers:

 

[Wolfy]

I am just not too sure what is the "best" way to go.

I don't think there is a right or wrong way, or even a 'best', depends on your technique and procedures. Usually recommended is a step size increase of about 4-10x, other than that just do what works for you and your setup.
I prefer to use 2L starters for ales, and outlined my procedure here: http://www.aussiehomebrewer.com/forum//ind...mp;#entry655707

 

[goatus]

Then once the loop is sterilized, you cool it in wort or in the agar (or even the air) before picking up yeast with it - the loop is only small so it cools very quickly.

Cool, Thanks. So flame, agar, yeast, scrape, done. Sounds too easy =)

I'm in Perth and buy them from a local pathology supplier.

Out of interest, where in Perth? Im looking to get set up for some yeast-farming.

 

[mxd]

well, my fist attempt (tried 2 different yeastes) was a bit of a disaster.

1) a couple of my test tubes didn't set (well they did, then when I went to innoculate them they went back to liquid)

2) I think the first attempt of of innoculating I may not have had any yeast on the loop, or I fried it

So back to the drawing board, and I will try again with my next fermentation.

 

[~MikE]

1) a couple of my test tubes didn't set (well they did, then when I went to innoculate them they went back to liquid)

hmm, sounds like someone's using gelatine...

 

[mxd]

guilty, I hadn't got to the shops by the time I wanted to start fermenting .

 

[mxd]

Another problem I have had is the rubber stoppers have popped out, maybe my test tubes aren't the best for slants ?

 

[barls]

if you want mate ive got some tubes for slants left from the last bulk buy i did.
pm me if interested

 

[mxd]

as an update, I made 40 blanks (with agar this time) in the tubes from barls and innoculated 8 of them from 1 us ale II pack. So far they appear to be doing the right thing. I'm will making a couple of starters on the weekend so that will be by next test