Yeast slant swap

[cheungja]

Does anyone on here keep yeast slants? If so, would you like to do a swap? I have a few strains at the moment

[the_great_okapi]

Assuming this thread isn't dead, yes, I keep some yeast strains on slant and might be up for a swap.

I remaster every 4-6 months and if I haven't used the strain for a good year or so I chuck them, meaning I only have 5-6 at any given time.

That said, I have on slant at the moment Fullers, Whitbread and Anchor ale strains alongside the Brewlabs bavarian pilsner strain and the alleged Spaten lager strain (WLP920).

Let me know if you are still interested.

[cheungja]

Yep! I'm interested in the Fullers. Is that cultured from a bottle of ale? I re-streak every 6 months

I have:
WLP002
WLP300
WLP510

WY1056
WY1335
WY1450
WY2565

Oakham Ales
Vermont

[Waffty]

If you believe what's written, then WLP002 is Fullers yeast. Plus please shoot me down but it's the same yeast they use for London Pride and ESB etc.

[hazelbrew]

how long does it take you to do this? how much effort to maintain yeast in this way?

[YeastWhisperer]

how long does it take you to do this? how much effort to maintain yeast in this way?

Maintaining a yeast bank on agar solidified media is a hobby unto itself. I have been brewing with home plated and slanted yeast since 1993. I no longer maintain cultures that are available via the home brew trade on slant. Once the novelty wears off, one discovers that it is easier and cheaper to purchase and re-pitch cultures that are available via the home brew trade than it is to maintain them on slant. My free time is worth more than $7.00US. The cultures that I keep on slant are the really expensive ones ($100.00US+), and the cultures that isolate from brewery samples.

Here's a photo that I shot of me holding one of my expensive cultures



The slant shown above held Siebel BRY 264, which is allegedly Molson's ale strain. It is of British origin. When all was said and done, the two slants in 16 x 100mm screw cap culture tubes that I received of this culture set me back around $175.00US (£120). Like I mentioned above, maintaining a yeast bank is a hobby unto itself--one that makes available cultures that are not obtainable via the home brew trade. BRY 264 is not obtainable via the home brew trade.

For those who do not know, Lallemand has owned controlling interest in the Siebel Institute since 2000. The slants that I ordered from Siebel were propagated at Lallemand's Biotech Research Institute in Montreal, Canada.

Here's the type of container that the NCYC uses to ship live cultures on slant




An old photo of my bank




A photo that shows a few my slants sealed with parafilm




Blank media cooling after being autoclaved in my kitchen

[Goulders]

I don't think it is that expensive, unless you want to maintain lots of different cultures.
I have bought (and reslanted) Thwaites and Wards from Brewlab. The latter is a very good clean yeast and was recommended to brew Coniston beers. I also have TV3 but I reslanted that after 2 years so probably not in the best condition. I'm planning on brewing a Coniston Bluebird type beer this weekend or next maybe, so will have to get a starter going tonight I think and think about reslanting again.

Edit: I have also successfully reslanted Gales yeast from a bottle of HSB

[the_great_okapi]

Answering hazelbrew's question:

It takes about half an hour to make the media and remastering takes two lots of half hour sessions (plating on agar then selecting colonies and reslanting.) You will need to do this 2-3 times a year. I am assuming a bank of half a dozen yeast strains.

When you need to grow up a starter it takes half an hour for media prep and roughly two lots of 15 min session (small 10 ml culture followed by 100 ml culture). From that point on, it is the same as making a conventional starter, albeit you won't need as big a starter volume.

I haven't included the 15 mins contact time for surface disinfection each time you do a manipulation, but you can spray and go do something else, unless you have a curious child or pet.

I would agree with the yeast whisperer that slanting is best for frequently used or unobtainable strains. An important point is that your yeast will be more vital (and viable) and it does work out cheaper than £10 to order in a yeast outside a regular hbs order.

If you keep some blank slants in the fridge, it only takes a minute to loop some of your bought yeast and keep the strain on a slant. If you brew again and need the strain, then great, if not, it is no great loss of time.

[Goulders]

Making blank slants as above. However...

Reslanting from one slant to another takes a couple of minutes if you have blank slants.

My routine when doing a starter is (assume you work in vicinity of a flame etc):

1. Take a loop of yeast from the slant to be used and transfer to a new slant (create 3 slants in total)

2. Add starter wort to slant and shake and add to 300ml starter wort.

3. For a 23l brew step up to 1l

Pitch at high krausen.

I have isolated cultures using a blank slant. A Petri dish isn't always necessary and I don't have any

[YeastWhisperer]

Making blank slants as above. However...
Add starter wort to slant and shake and add to 300ml starter wort.

Starting slanted yeast in 300ml of starter wort is playing with fire. Yes, it may work most of the time, but you are eventually going to get burned when you least expect it. You will exhaust the dissolved O2 and the ergosterol that was synthesized from it long before the yeast cells meet maximum cell density. I start slants using 40ml of autoclaved 5% wort, and I find that volume to be pushing the outside of envelope. The correct way to start a culture from slant is 10ml (autoclaved) -> 100ml -> 1000ml, which is a 10:1 step ratio with the initial inoculation being small enough to ensure rapid ownership.[/quote]

I have isolated cultures using a blank slant. A Petri dish isn't always necessary and I don't have any

Plating media prepared in a Petri dish makes the cell dilution process infinity simpler. One cannot be certain that one has a pure culture unless when is harvesting a single well-formed CFU (colony forming unit) from a plate.

[YeastWhisperer]

If you keep some blank slants in the fridge, it only takes a minute to loop some of your bought yeast and keep the strain on a slant. If you brew again and need the strain, then great, if not, it is no great loss of time.

That's not a reliable way to produce contamination-free slants. Liquid cultures should be plated for singles (a.k.a. CFUs) to ensure that one has a pure culture. Regardless of their claims, the liquid cultures produced by the two big yeast propagators are not 100% contamination free.

Here's a photo that I shot of Scottish and Newcastle's yeast strain on a plate:



Two well-isolated, hemispherical shaped, creamy white CFUs (colony forming units) in the lower right-hand quadrant of the plate were selected for propagation to slant, one CFU per slant. In that form, they are known as isolates of Scottish and Newcastle's strain much in the same way that W-34/70 is the 70th isolate of Weihenstephan strain number 34 (W-34/78 is another commonly used isolate from this strain). Two isolates from the same single-strain culture can produce slightly different beers. A well-formed CFU is composed of the offspring of a single yeast cell; therefore, it is by definition a pure culture.

An important point is that your yeast will be more vital (and viable) and it does work out cheaper than £10 to order in a yeast outside a regular hbs order.

It only works out to be cheaper than £10 if one does not factor one's time into the equation. As I mentioned above, maintaining a yeast bank on solidified media is a hobby unto itself. It has to be approached from the point of view, or one will eventually tire of the work necessary to maintain a contamination-free yeast bank. Cropping and repitching is a more viable strategy to lower the cost of yeast for most brewers.

Back in the nineties, I used to purchase many of my yeast strains on slant from a company in California called BrewTek. BrewTek was the original home brew trade source for the yeast strain known today Wyeast 1450 Denny's Favorite 50. The stain was known as BrewTek CL-50 California Pub Brewery Ale. Denny Conn acquired Wyeast 1450 from BrewTek as CL-50. With the help of a friend who had access to cryostorage, Denny managed to keep the culture alive after he lost interest in dealing with slanted yeast. Denny eventually convinced David Logsdon to add the strain to the Wyeast catalog.

[Goulders]

I disagree Yeastwhisperer about adding to 300 ml to a FULL slant. It is recommend by Brewlab as well. If I was taking a loop of yeast then, yes, 10ml >100ml would be appropriate. And I autoclave my wort btw.

[YeastWhisperer]

I disagree Yeastwhisperer about adding to 300 ml to a FULL slant. It is recommend by Brewlab as well. If I was taking a loop of yeast then, yes, 10ml >100ml would be appropriate. And I autoclave my wort btw.

That's a compromise recommendation. If Brewlab suggested the proper way to start a slant, few home brewers would purchase their slants. I can guarantee that starting a Brewlab slant with 300ml of sterile wort on this side pond would be a mistake. Brewlab slants do not travel well, which is why I re-plated the Scottish and Newcastle slant that I received from Brewlab.

I start all of my cultures by dissolving the yeast that is on the surface of the slant after subculturing it. I would never use 300ml to start a culture from slant because the cell count is two low for the amount of dissolved O2, which leaves one with a reduced number of cells that are not in peak condition when stepping or pitching the starter. A step of much more than 20-to-1 cell count-wise is not good for the cells. A 20-to-1 increase in cell count requires the culture to double log(20) / log(2) = 5 times (rounded up). That increase does not seem like much, but the mother cells that were pitched have to share the ergosterol and unsaturated fatty acid reserves that they synthesized with five generations of daughter cells. A mother cell shares her ergosterol and UFA reserves with each daughter she buds. Daughter cells become mother cells during the next replication period, which is why yeast cell count growth is exponential, not linear.

Original mother cells bud 5 times
First generation daughter cells bud 4 times
Second generation daughter cells bud 3 times
Third generation daughter cells bud 2 times
Fourth generation daughter cells bud 1 time

The ergosterol reserves are divided across a population twenty times larger with a 20-to-1 increase in cell count. Ergosterol and UFAs make the cell plasma membrane more pliable, which, in turn, makes it easier for nutrients to enter a cell and waste products to exit it. Yeast cells with low ergosterol and UFA reserves are unhealthy cells. One may get away with pitching cells from a 300ml starter grown from slant in a 1.040 gravity or lower wort, maybe even a 1.050 wort without any major hiccups. However, after that gravity is reached, cell membrane health starts to become critical. A beer with a 1.050 original gravity is not considered to be a high gravity beer in the United States.

[McMullan]

I’m inclined to agree with YeastWhisperer. The goal of a starter/culture is population growth, not fermenting wort. Starters are sometime mistaken for ‘mini beers’. They aren’t. Stepping up too much is wasting time and resources, as YW has explained nicely. Having said that, I do resuspend a yeast slant in 400-500ml wort to culture a population sufficient to successfully ferment a batch up to 23L, usually around 1.050. I should note that this is with my slants, not BrewLabs. My slants have more yeast cells.

[url=https://flic.kr/p/GRUzdk]

[stevej383]

May i ask what %s of Agar to dme or wort / water people use to make the slants