Calling All Yeast Platers!

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Ok i finally got off my bum and took a pic

the left is the little blood tube i was talking about

the mid is the 20Ml tubes that are great

and right is the streaked plate, i now know i had to much yeast on the wire and will do it better next time, however there is some single cells

Photo_008.jpg
 
If you can see visible yeast on your probe, you have too much. As Kai said, you need a plate the size of a cricket pitch to effectively streak.
 
i plucked two small dots off this dish and placed onto a slant (dont plan to use) This is all practice so if/when i stuff it up, its only a few cents wasted... once i have it down pat i will then move to my yeast bank and start moving to this method....

first time is always blind to a point... but we will all get there :)
 
Gout, practise is good.

Sos, moulds are common on plates. This is why when you streak a plate up, don't just do one, do a couple. Hopefully one will be mould free.

To inhibit mould growth, you need some sort of bacteria inhibitor in the agar solution. A small bit of antibiotic tablet as per GLS's notes works. Or some sodium or calcium propionate.
 
pint of lager said:
Sos, moulds are common on plates. This is why when you streak a plate up, don't just do one, do a couple. Hopefully one will be mould free.

To inhibit mould growth, you need some sort of bacteria inhibitor in the agar solution. A small bit of antibiotic tablet as per GLS's notes works. Or some sodium or calcium propionate.
[post="59020"][/post]​
Good tips. There is someone at work who spent a year in a yeast lab so she has given me some good tips too. I have some scrap perspex and I might try to make a miniature culturing hood. I also scored one of those 254nm wavelength UV tubes which I might rig up inside the hood to sanitize everything before I get going. Another brewing project.
 
Steve Lacey said:
sosman said:
Mouldy petri:
More info at http://brewiki.org/Yeast/Culturing
[post="58866"][/post]​
Coupla tips for reducing contamination. When you do the quadrant method, don't reflame the loop. Just work your way around quickly from one dip into the yeast source. In other words: flame loop, dip loop, pick up plate out of lid (it is upside down), turn and work above a low gas flame now if possible and/or hold breath, streak one, rotate plate 90 deg, streak two, rotate, streak three, rotate, streak four, replace plate into lid. Exhale. From picking up dish to replacing it should take all of 10 to 20 sec at most.

I then pop the plate into a ziplock bag and then that into a biscuit tin. Actually, it goes into the ziplock bag after pressure cooking and during the day or two wait before streaking for the condensation to bugger off.

Wow, that yeast supplies place in Colorado has some stuff. I'd like to know how to use all those viability indicators and things...and I wonder what the tubing is for? Shame they seem to only have disposable loops. I aquired my loop from a mycologist friend, so I don't know what to tell people about getting their own.
[post="58976"][/post]​
Good tips, I will try that. I was under the impression that leaving the dish for more like a week was needed to see if it had something nasty growing on it. Having said that, I probably infected mine during the streaking part because they were clear after a week.

Oh yes, my homemade innoculating loop:
InnocLoop.jpg
 
Steve Lacey said:
Coupla tips for reducing contamination. When you do the quadrant method, don't reflame the loop. Just work your way around quickly from one dip into the yeast source.
[post="58976"][/post]​
I went ahead with your tip Steve and voila, no mould (2 out of 2). I guess I did improve my other techniques also.
Petri3068.jpg
 
Congrats SOS, it's looking good. Hope to up to that some time.
And I see Post 1000 is about to pop up for you- Wuhoo. Millenium poster.

Cheers
Borret
 
OK here's a few photos of my first attempts at streaking.
Comments?
Petri3_4.JPG
Petri2.JPGPetri1.JPG
 
Hoops said:
OK here's a few photos of my first attempts at streaking.
Comments?
[post="65390"][/post]​
:beer:
Give me the streaker from the 1982 grand final any day.
 
Airgead said:
Gout said:
where does everyone get their agar? i have looked around and found it very expencive

mind you in 500g or 5Kg (got upto $1800) I gather i only need about 50-100g to last a long time
[post="55057"][/post]​

Local chinese supermarket. Food grade agar agar powder. About $2 for a 25g packet. Its used a lot in asian deserts and things.
[post="55060"][/post]​

I received my first slants the other week & had no option but to make up an inoculation loop, sterilise three 10ml starters (just in case of contamination), & have a go building a starter from a slant. I am happy to say that all three starters are alive & well. It was a lot easier than I expected so I contacted a mate in Brisbane to get me some agar to continue my yeast culturing experiences. As I did not specifically mention agar powder I finished up with the agar in the pic. I don't suppose it really matters as it should still dissolve with the DME in the pot. Please tell me if I'm wrong here.

:beer:

Edit ---- My first attempt at posting a pic didn't turn out as expected :( . Will try again when I resize it.
Edit 2 ---- Please bear with me. I have never used a digital camera before. This should work.
 
Tidalpete said:
Airgead said:
Gout said:
where does everyone get their agar? i have looked around and found it very expencive

mind you in 500g or 5Kg (got upto $1800) I gather i only need about 50-100g to last a long time
[post="55057"][/post]​

Local chinese supermarket. Food grade agar agar powder. About $2 for a 25g packet. Its used a lot in asian deserts and things.
[post="55060"][/post]​

I received my first slants the other week & had no option but to make up an inoculation loop, sterilise three 10ml starters (just in case of contamination), & have a go building a starter from a slant. I am happy to say that all three starters are alive & well. It was a lot easier than I expected so I contacted a mate in Brisbane to get me some agar to continue my yeast culturing experiences. As I did not specifically mention agar powder I finished up with the agar in the pic. I don't suppose it really matters as it should still dissolve with the DME in the pot. Please tell me if I'm wrong here.

:beer:

Edit ---- My first attempt at posting a pic didn't turn out as expected :( . Will try again when I resize it.
Edit 2 ---- Please bear with me. I have never used a digital camera before. This should work.
[post="83412"][/post]​

Success :) My first & last stuff-up with piccies (hopefully) :beerbang: .
 
You'll be able to use that agar no worries. It liquefies at around 85C but solidifies somewhere in the 30-40C mark.
 
NRB said:
You'll be able to use that agar no worries. It liquefies at around 85C but solidifies somewhere in the 30-40C mark.
[post="83497"][/post]​

Thanks for your response NRB. Just playing it safe. I am typing this out of the corner of my right eye whilst admiring your lovely avatar. :)

:beer:
 
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