Q Regarding Yeast Slanting

[SicOfVic]

Hi All,

I gave yeast slanting a whirl on the weekend.

The process went well, thanks to the guides available here, however it appears my wort did not set correctly. There is a drop or two of liquid in each test tube. I used around 20g of Agar to 1L of wort, which was well up on the packet suggestion. The slants have been sitting at room temperature for a few days now.

Is it a problem if I have a few drops of liquid in each test tube before I innoculate with yeast?

Thanks

 

[samhighley]

Is it a problem if I have a few drops of liquid in each test tube before I innoculate with yeast?

That's just some condensation from when you added the hot wort mixture to your test tubes.

It shouldn't be a problem, but I usually pour it off when it comes time to inoculate.

 

[raven19]

My first batch of slants did not have enough gelatine in them, as such on a warm day, all the yeast fell through the slants to the bottom! Hence I ditched them and started again.

I went with a 50/50 mix of malt and gelatine with water to make up around 1040 mix. This set really well and my slants work a treat.

In your case it should be fine, but maybe plan on increasing the gelatine for your next lot of slants.

2c.

 

[samhighley]

In your case it should be fine, but maybe plan on increasing the gelatine for your next lot of slants.

He didn't use gelatine, he used agar. In this situation I believe it is just condensation he is seeing on his slants.

This is how the slants will look when the yeast have bloomed on the surface of the slant mixture:

 

[SicOfVic]

He didn't use gelatine, he used agar. In this situation I believe it is just condensation he is seeing on his slants.

This is how the slants will look when the yeast have bloomed on the surface of the slant mixture:

Great stuff, thanks guys. I'll innoculate a few on the weekend and see how they go.

Looking forward to getting a nice library together.

Cheers

 

[slacka]

He didn't use gelatine, he used agar. In this situation I believe it is just condensation he is seeing on his slants.

This is how the slants will look when the yeast have bloomed on the surface of the slant mixture:

Are they the LS22-30 from ProSciTech?

I'm putting together a purchase order and want to know the outer diameter of these babies so that I can also get the corresponding tube rack.

 

[The Mad Hopper]

I've made slants at 4% agar in wort (40g agar to 1L) and they set fine at that. I would think that it would be best not to take it to a really high percentage of agar. Yes it will be more solid, but I'm not sure the yeast are going to be happy about that (and you're just wasting money!).

 

[~MikE]

20g/L is PLENTY, anything more is a waste. the drops are just condensation, pour it off or leave it in there, doesn't really matter. if the condensation carries some cells to the edge of the media, it could start growing between the media and the tube. there's nothing wrong with this, it just can be annoying.

 

[altone]

Maybe off thread, but on topic as per the title (maybe?)

Are there culture tubes / test tubes and lids that can be easily sterilised (in a pressure cooker) after each use or do you guys use glass tubes and oneshot the lids?

I still have quite a few unused plastic culture tubes I use to gather "cleaned" yeast for reuse but looking at what I will need for slants in the future.

I'm only practising technique ATM - until I'm happy I've got it down pat, then I'll start making
slants for real.

Ta

 

[raven19]

Are there culture tubes / test tubes and lids that can be easily sterilised (in a pressure cooker) after each use or do you guys use glass tubes and oneshot the lids?

Any lab supply store will supply easily sterilised test tubes.

Try here for a typical online shop, or here for one of many AHB threads... cant find the most recent one Sully organised though...

 

[altone]

Any lab supply store will supply easily sterilised test tubes.

Try here for a typical online shop, or here for one of many AHB threads... cant find the most recent one Sully organised though...

Yep I've got some borosilicate tubes - no problem there, I was more questioning the plastic caps - will try mine in the
pressure cooker next time I'm going to gather some yeast and see what happens.

If anyone knows of a source for tubes/caps that can be sterilised in a pressure cooker, feel free to post.

Thanks

 

[raven19]

Yep I've got some borosilicate tubes - no problem there, I was more questioning the plastic caps - will try mine in the
pressure cooker next time I'm going to gather some yeast and see what happens.

I have reused my plastic caps no worries, I just use a heatproof bowl inside a bigger pot with steam/boiling water for 15 minutes and have had no issues.

Give it a go, just make sure you have a backup sample of yeast just incase!

 

[Stuffa]

Slacka,
Proscitech gave me the following info:
The LS22-30L tubes have an outer dimension of ~25mm. So I would recommend the
Tube racks LD8 on page
http://www.proscitech.com/cataloguex/onlin...?page=l12#ld5-b

The Blue, Red, White and Yellow colours are currently in stock at $12.00
per rack.

 

[altone]

I have reused my plastic caps no worries, I just use a heatproof bowl inside a bigger pot with steam/boiling water for 15 minutes and have had no issues.

Give it a go, just make sure you have a backup sample of yeast just incase!

Thanks mate - I will try 1/2 reused caps 1/2 new caps to be safe - not really a major concern if I lose the yeast,
just practicing before I do it for serious.

Methinks this is something you HAVE to do 100% right or it'd be a total waste of time.

 

[The Mad Hopper]

I've used something very similar to LCA04 and they work a treat. If you can get something like this that's presterilised it will give you peace of mind as you can be certain you won't get infection from the tubes themselves. At 25 cents each just think how much you'll save on buying yeast each brew!

 

[gava]

attempting some yeast slanting... I've read a few posts on "how-to" it says to use ethyl alcohol to clean your needle, I cant find where to purcahse it.. is there anything else I can use?

cheers

 

[Online Brewing Supplies]

attempting some yeast slanting... I've read a few posts on "how-to" it says to use ethyl alcohol to clean your needle, I cant find where to purcahse it.. is there anything else I can use?

cheers

Sorry if Im off track here but dont have time to read the whole tread.Heat, Bunsen burner.Get it to glow then quench in the slant agar.Pick your yeast and then wipe on the slant.PM me if you need more info.
GB

 

[~MikE]

attempting some yeast slanting... I've read a few posts on "how-to" it says to use ethyl alcohol to clean your needle, I cant find where to purcahse it.. is there anything else I can use?

cheers

if you don't have a bunsen burner, you can sterilize with ethanol (methylated spirits is typically >95% ethanol and is what i use). have a candle or some flame nearby, dip in ethanol to sterilize, pass over flame to burn off excess, loop is ready to use

 

[gava]

Excellent.. Cheers for that.. I'll give it a go tonight.. lets hope I dont set fire to myself.

if you don't have a bunsen burner, you can sterilize with ethanol (methylated spirits is typically >95% ethanol and is what i use). have a candle or some flame nearby, dip in ethanol to sterilize, pass over flame to burn off excess, loop is ready to use

 

[3G]

I do mine similar to mikE, but the opposite order, i flame over the stove, dip in methoto cool then slant away