Jump to content



Photo
* * * * * 3 votes

From Slant To Starter - In Pictures


  • Please log in to reply
52 replies to this topic

#1 Wolfy

Wolfy

    Beer God

  • Members
  • PipPipPipPipPipPipPipPipPip
  • 3,907 posts
  • Joined 18-December 08
  • Location:Melbourne

Posted 16 July 2010 - 12:11 AM

As with most things yeast related, there are many ways to achieve the same result, but here the process I use to reculture yeast from a slant and grow it up to a starter of suitable pitching volume.
In this example I'm using a 6m old home-made slant of Wyeast Kölsch yeast (2565) and I wanted to make a starter that was 2L in volume.
The starter was stepped up from about 15ml, to 100ml, 400ml and then 2L.

First step was to let the slant come up to room temp, gather the ingredients and clean and clean/sanitise everything:
Posted Image

The saved wort I had kept in the fridge for a couple of months was a bit gunky, so I made the starter wort by boiling about 175g of LDME (and some yeast nutrient) in a little more than 2L of water - aiming for an OG a bit above 1.030.
While the wort was still boiling hot I carefully tipped it into the various containers, topped them with aluminum foil and left them to cool:
Posted Image

The 15ml test tube of wort was quickly cooled in some cold water and then added to the slanted yeast.
Using a (plastic) inoculation loop I carefully scraped the yeast from the surface of the slant, trying to remove all the yeast but leave the solid agar mix behind:
Posted Image

After tipping the 15ml wort and yeast back into the clean test tube, I kept it on my computer desk, so I'd be reminded to shake it often.
The temperate was generally about 20C and the stater was allowed to ferment out for 24 hours, before stepping up to 100ml:
Posted Image
There is already a small layer of yeast on the bottom of the test tube.
At this stage due to the very small volume of beer a smell/taste test is not going to tell you much, as I suspect there were a few dead yeast cells scraped off the slant.

The 100ml starter was put onto my el-cheapo DIY stir plate and allowed to ferment out for another 24h, before stepping it up to 400ml:
Posted Image
The foam on the yeasty-starter on the left is from yeast fermentation, and the plain wort on the right from me shaking the crap out of it for about 15 mins before pitching the yeast.
(I had a little left over wort so I added some agar agar and made the new blank slants that can be seen in the background.)

After another 24h on the stir plate, the 400ml starter had created a nice layer of yeast, which I left to settle out for a little while so I could take a taste/smell sample:
Posted Image
Kölsch yeast is not the nicest tasting stuff so I wanted to try to sample some beer without too much yeast in it. :)

After it had passed the taste-test it was pitched into the final 2L volume:
Posted Image

The yeast was still crawling out of the top of the flask after 24 hours, so I left it on the stir plate for another day to let it complete fermenting.
Posted Image
The 9l square plastic container may look ugly, but there is no way the yeast can over-flow it and short out the electronics in the stir plate. :)

After one more day - this time in the fridge:
Posted Image

Any yeast that did not escape in the previous step settled to the bottom of the flask:
Posted Image
The spent beer is now ready to be decanted, so yeast can be pitched into a batch of beer.

Edited by Wolfy, 16 July 2010 - 12:37 AM.


#2 Pete2501

Pete2501

    Beer God

  • Members
  • PipPipPipPipPipPipPipPipPip
  • 888 posts
  • Joined 16-June 08
  • Location:Perth

Posted 16 July 2010 - 12:33 AM

Nice post Wolfy. :beerbang:

#3 ~MikE

~MikE

    lvl 23 Comrade

  • Members
  • PipPipPipPipPipPipPipPipPip
  • 606 posts
  • Joined 02-July 07

Posted 16 July 2010 - 12:36 AM

nice work, IMO considering you're using a stirplate you could happily go slant -> 50ml culture -> 1500ml starter.

#4 Wolfy

Wolfy

    Beer God

  • Members
  • PipPipPipPipPipPipPipPipPip
  • 3,907 posts
  • Joined 18-December 08
  • Location:Melbourne

Posted 16 July 2010 - 12:45 AM

nice work, IMO considering you're using a stirplate you could happily go slant -> 50ml culture -> 1500ml starter.

Most likely true, but if I'm not in a hurry I do tend to be a little conservative, and play things on the safe side.
I was also slightly concerned about the yeast/slant viability, especially when the first step (and the second to a lesser extent) had a noticeable burnt-rubber smell (I suspect from autolysis of the yeast on the slant) . ;)

#5 bjay

bjay

    Partial Man

  • Members
  • PipPipPipPipPip
  • 136 posts
  • Joined 22-August 09
  • Location:Frankston

Posted 16 July 2010 - 07:47 AM

This is going straight to the pool room
Thanks wolfy very infomative

cheers
bjay

#6 WarmBeer

WarmBeer

    Unhappy camper

  • Banned
  • PipPipPipPipPipPipPipPipPip
  • 3,010 posts
  • Joined 17-April 08

Posted 16 July 2010 - 08:06 AM

Wolfy,

The wort in the 2lt flask looks considerably darker than the other 2.

Is this just due to the depth of the wort, or a different batch?

PS. Awesome guide. :kooi:

#7 MeLoveBeer

MeLoveBeer

    Beer God

  • Members
  • PipPipPipPipPipPipPipPipPip
  • 621 posts
  • Joined 20-April 10

Posted 16 July 2010 - 08:25 AM

Thanks Wolfy, we're now starting to build up a great collection of yeast related threads; there is no excuse now for those wanting to split, farm, wash and start yeast.

#8 NickB

NickB

    I haven't had a C**t all night, Drinkstable....

  • Members
  • PipPipPipPipPipPipPipPipPip
  • 4,515 posts
  • Joined 29-June 06
  • Location:Collingwood Park, Qld

Posted 16 July 2010 - 08:47 AM

Perfect timing - I'm going to be culturing up a starter from a slant I was given sometime today, and was really trying to get my head around the process. Thanks Wolfy!

Cheers

#9 Thomas J.

Thomas J.

    Beer God

  • Members
  • PipPipPipPipPipPipPipPipPip
  • 741 posts
  • Joined 26-January 10
  • Location:A very small place.

Posted 16 July 2010 - 08:53 AM

Funny I finished a sequence just like that yesterday (pitched 4L starter for two 23L ales) and my Mum stopped by as I was washing the cake from my Irish Red (WY 1084) afterwards, she watched me for a few mins and then said that her old boss at the yeast factory might be wanting to get in contact with me later. Couldn't have asked for a better compliment.....

#10 geoff_tewierik

geoff_tewierik

    Beer God

  • Members
  • PipPipPipPipPipPipPipPipPip
  • 676 posts
  • Joined 11-November 07
  • Location:Holland Park West, Brisbane

Posted 16 July 2010 - 08:57 AM

Congrats on taking the time and putting in the effort to put the pictyure show together.

I did cringe at the addition of wort to the slant and scraping the yeast off, it's a waste of a good slant IMO.

Preferred method would have to be to take, asceptically, a small amount of yeast from the slant with an innoculating loop and add that to your first bit of wort. This will allow you to retain the slant for future brews/comparison tests and allow you to maintain a pure culture strain for a longer period of time.

The above comment is based entirely on there being just the one slant, if you've got a bunch of the same yeast on a shed load of slants then it's a non issue for you.

YMMV.

Cheers,

GT

#11 Fourstar

Fourstar

    doG reeB

  • Members
  • PipPipPipPipPipPipPipPipPip
  • 6,204 posts
  • Joined 31-October 07
  • Location:Mount Waverley, VIC

Posted 16 July 2010 - 09:16 AM

Beautiful work wolfy. Great commitment to document w/photos all of that over a few days. More effort than what i would put in! Pretty much the exact same procedure i perform except all of my erlenmyers have been smashed. Two of them from vibrations from the screws mounting my fan on the DIY stirplate. These have now been taped over to save any future flasks. <_< The past two ive been doing in some 1L and 2L fowles varcola preserving jars and are doing the same job. only issue is boiling the starter wort in a little saucepan.

The difference i have in my procedure too is i will just dump the 30ml or so of wort into the testtube, shake and leave to ferment out, once done i shake again and transfer into my flask. unless its one of the early crappy gelatine slants i made, it seems to work well without taking all the agar with it. :lol:

#12 QldKev

QldKev

    Brew Dude

  • Moderators
  • 7,906 posts
  • Joined 21-June 05

Posted 16 July 2010 - 10:17 AM

Good write up. I think it should get a few more people interested in farming yeast. I've always just used test tubes of yeast. What would be the pros/cons of slants over a test tube of yeast?

QldKev

#13 Sammus

Sammus

    Amateur Brewer

  • Members
  • PipPipPipPipPipPipPipPipPip
  • 3,281 posts
  • Joined 16-March 06
  • Location:Mount Keira

Posted 16 July 2010 - 10:35 AM

nice work, IMO considering you're using a stirplate you could happily go slant -> 50ml culture -> 1500ml starter.


you probably could, but they say the max step for optimal growth should be between 5x and 10x. I do slant -> 10ml - 50ml - 250ml - 2.5L for lagers, or 10ml - 100ml - 1L for ales.

#14 ~MikE

~MikE

    lvl 23 Comrade

  • Members
  • PipPipPipPipPipPipPipPipPip
  • 606 posts
  • Joined 02-July 07

Posted 16 July 2010 - 10:53 AM

...but they say...

who says? :ph34r:

you're probably right though, but given he's using a stirplate, it means he could easily afford to be lazy - if your starter vessel can maintain optimal growth conditions with agitation and added oxygen, and you're satisfied with your sterilisation procedures you could happily step up to up to ~ 50X i think.

#15 WarmBeer

WarmBeer

    Unhappy camper

  • Banned
  • PipPipPipPipPipPipPipPipPip
  • 3,010 posts
  • Joined 17-April 08

Posted 16 July 2010 - 10:56 AM

The difference i have in my procedure too is i will just dump the 30ml or so of wort into the testtube, shake and leave to ferment out, once done i shake again and transfer into my flask. unless its one of the early crappy gelatine slants i made, it seems to work well without taking all the agar with it. :lol:

So the wort in the test-tube doesn't disolve the agar overnight?

#16 Fourstar

Fourstar

    doG reeB

  • Members
  • PipPipPipPipPipPipPipPipPip
  • 6,204 posts
  • Joined 31-October 07
  • Location:Mount Waverley, VIC

Posted 16 July 2010 - 11:26 AM

So the wort in the test-tube doesn't disolve the agar overnight?


nope. its melting point is like 95 deg from memory.

#17 cubbie

cubbie

    Beer God

  • Members
  • PipPipPipPipPipPipPipPipPip
  • 457 posts
  • Joined 28-January 05
  • Location:Perth

Posted 16 July 2010 - 11:42 AM

So how many yeast cells do you estimate you have in the final starter?

#18 Sammus

Sammus

    Amateur Brewer

  • Members
  • PipPipPipPipPipPipPipPipPip
  • 3,281 posts
  • Joined 16-March 06
  • Location:Mount Keira

Posted 16 July 2010 - 11:53 AM

who says? :ph34r:

you're probably right though, but given he's using a stirplate, it means he could easily afford to be lazy - if your starter vessel can maintain optimal growth conditions with agitation and added oxygen, and you're satisfied with your sterilisation procedures you could happily step up to up to ~ 50X i think.


I knew someone would say that :P

I've been searching for the article since I posted that...there was some research that sounded convincing that concluded what I said... now just to find it :P

#19 WarmBeer

WarmBeer

    Unhappy camper

  • Banned
  • PipPipPipPipPipPipPipPipPip
  • 3,010 posts
  • Joined 17-April 08

Posted 16 July 2010 - 12:15 PM

nope. its melting point is like 95 deg from memory.

Ah, noice.

Hopefully you and Wolfy can give some hints and tips on the subject at the swap tomorrow.

Beginning to seriously wish I'd paid more attention during high school Chem prac.

#20 ~MikE

~MikE

    lvl 23 Comrade

  • Members
  • PipPipPipPipPipPipPipPipPip
  • 606 posts
  • Joined 02-July 07

Posted 16 July 2010 - 12:16 PM

I knew someone would say that :P

I've been searching for the article since I posted that...there was some research that sounded convincing that concluded what I said... now just to find it :P


hehe, no no i believe you. in theory stepping it up on a smaller scale would definitely the safest way to go. in practice the difference would be negligible with optimum growth conditions and good sterilisation.

nope. its melting point is like 95 deg from memory.

yups, it melts at ~85C (although i take it to near boiling point to get it to dissolve properly) and solidifies at ~40C and it's a disaccharide polymer that isn't metabolised, making it far better than gelatine which will liquify in the presence of proteases.

Edited by ~MikE, 16 July 2010 - 12:23 PM.