Making Slants- How Much Agar To Use?

[peas_and_corn]

Hello,

I tried to make some blanck slants for my yeast farm, but as I was filling the test tubes, tragedy struck! It went all gluggy and bubbled up as it left the syringe (I'm guessing due to the gluggyness).

SOO... If I were to use LDME, what ratio water/LDME/agar agar should I use?

Cheers,
Dave

 

[Fourstar]

Personally,

2:100 ratio of agar:wort. e.g. 2g Agar 100ml wort.

Make wort 1:10 ratio LDME:water

Cheers!

 

[peas_and_corn]

So that would mean (for example):

500mL water
50g LDME
10g agar

...right?

 

[wambesi]

I'm trying to decipher my notes I wrote on the guide I printed out.
I think I used 2g per 250mL wort.
The wort itself was a 1040, made up at a litre.

I really have to find all the notes I used to have, thankfully now I'm transferring everything onto the thumbdrive (yes it's backed up!)

 

[unterberg]

Normally LB agar is made with around 1,5-2% agar (we used 15g per liter with Bacto Agar).
For the LDME I wouldnt make it up to 1:10. Waste of LDME.
5% LDME should be more than plenty.
I would rather think of adding some extra yeast nutrient - maybe 0.5%.

 

[peas_and_corn]

I have wyeast nutrient, would that be fine?

Also, do you guys boil it, or simmer? For how long?

 

[unterberg]

I have wyeast nutrient, would that be fine?

Also, do you guys boil it, or simmer? For how long?

I reckon that nutrient should be fine. The yeasties are normally happier with some extra amino acids and salts.
I would boil it till the agar is dissolved completely. Shouldnt take longer than a few minutes.
Agar will melt around 80C so a quick boil with stirring is fine.
I would actually boil it to sterilze the whole lot - yeast is prone to get infections from nasty bacteria.
So maybe a 10 minute boil should do the trick.
Then wait for it to cool before you poor anything.
It will only get solid around 35-40C so there is time to let it cool down - spilling it with 50C is not as painful as with 90C
And be aware that the agar will sweat - meaning it will dehydrate if left on open air - so proper sealing is important for storage.

 

[peas_and_corn]

Awesome. Cheers everyone! It makes a bit more sense now.

 

[thunderchild]

So that would mean (for example):

500mL water
50g LDME
10g agar

...right?

dumb question......whats agar?

 

[peas_and_corn]

POwdery stuff, similar to gelatin, which hardens the 'wort' for the slant.

 

[wambesi]

dumb question......whats agar?

Its like gelatin but made from seaweed.
Used a lot on the science world too.
Check it out here

 

[Fourstar]

dumb question......whats agar?

its taken from seaweed. veggo safe gelatine

 

[Jase71]

Anyone know where I can get agar ? ive been looking in all the big supermarkets, and about four asian grocery stores - so far nothing!

 

[wambesi]

Anyone know where I can get agar ? ive been looking in all the big supermarkets, and about four asian grocery stores - so far nothing!

I get mine from the asian grocery store in Liverpool Westfield, also another one near where I work in the city.
They should stock it. Did you try yourself or ask as well?

I found some of them don't have any english labels (or they are small ones on the back) and can be quite hard to find.

 

[Jase71]

Looked and asked (although on a coule of occasions they had no idea what I was asking for.... ) and have also found there to be sections that have all sorts of extract powders.

Any chance of telling me where in the City you are referring to ....Not Burlingtons by chance ? That's my next port of call.

 

[Franko]

remember you can always use gelatin instead of Agar Agar

Franko

 

[mickoz]

Looked and asked (although on a coule of occasions they had no idea what I was asking for.... ) and have also found there to be sections that have all sorts of extract powders.

Any chance of telling me where in the City you are referring to ....Not Burlingtons by chance ? That's my next port of call.

Hi Jase,

Ask them for aga aga - little a's not A as in Aim - a as in apple

Don't use gelatin, it melts a too low a temperature. You will end up with sloppy slants

Regards

Mick

 

[wambesi]

Looked and asked (although on a coule of occasions they had no idea what I was asking for.... ) and have also found there to be sections that have all sorts of extract powders.

Any chance of telling me where in the City you are referring to ....Not Burlingtons by chance ? That's my next port of call.

No this is just a little grocery store on Pitt St.
If you still have dramas let me know, I'm sure I could send some to you or something.

 

[Jase71]

Thanks all - Schooey has been kind enough to offer to send me some of his surplus agar , top bloke that he is.

 

[Fourstar]

All Asin grocers i frequent always have agar floating around with the food colourings/essences. probably because its used in desserts. YOu can either get the raw version (like gelatine leaves) or powdered in a smalll clear 20g packet. soe will have pictures of jelly on the front in a yellow paket if that helps in the future!