What about a Jims Beer Kit yeast Bank

[Wez]

Great to see you back DaaB

[J_P]

Welcome back stranger

[iowalad]

Wise words Daab and nice to have you back!

[Jim]

what i really meant was that with white labs and wyeast i have a frame of reference ie i know that a certain yeast is from X or Y commercial brewery.

Whitelabs and Wyeast don't actually make any claims that their yeasts are any particular strain although with a few of their yeasts they do imply so.
Plenty of people have make assumptions and educated guesses at which strains are which but these assumptions and guesses have been brought into question in the past.

I've heard it said on several occasions that the ESB strain doesn't exactly replicate the Fullers strain and from personal experience I can say that the Ringwood strain isn't entirely like the stuff I get from the Ringwood brewery. Indeed the stuff from the brewery is made up of multiple strains which as far as I am aware are difficult to culture and keep on slants.
For these reasons I don't think certain of the heritage of an individual strain bought from Wyeast or White Labs.

Fwiw, I wouldn't get too tied up with using a particular strain for a particular ale, you may not be able to get it to work for you in the same way as the original brewery does anyway. I certainly can't get the Ringwood strain to work through a beer the same way the Ringwood brewery can, for that i'd need to use tall rectangular fermenters and use pumps and fish tails for rousing.

Personally I think it is better to select a yeast using the available descriptions whether it be Wyeast, White Labs or Brew Labs and experiment with it and find out how to get the best from it. At least if you do that, if you start to question the health of your cultures or reach the stage where you aren't happy to reuse the slurry you can make a quick phone call and get a fresh culture prepared under proper lab conditions.

On a slightly different matter, with your microbiologists hat on, is it possible to pitch starter which might contain a small amount of bacteria and reculture from the starter to the point where you effectively ferment out the bacteria due to the conditions of the beer being inhospitable for the bacteria and end up with a clean or relatively clean yeast sample?

Talking about Ringwood yeast, I took that sample out of the fridge a couple of hours ago ready for tomorrow's brew, and it's already trying to climb out of the bottle!

Do you usually have to rouse it? It looks as though it won't need it!

[Jim]

It's all mouth and no trousers Jim. You'll soon get the measure of it, keep a bucket and cloth by the fermenter though and also your paddle and a hand sprayer full of no rinse Betadine solution.

[steve_flack]

On a slightly different matter, with your microbiologists hat on, is it possible to pitch starter which might contain a small amount of bacteria and re-culture from the starter to the point where you effectively ferment out the bacteria due to the conditions of the beer being inhospitable for the bacteria and end up with a clean or relatively clean yeast sample?

Depends on the bacteria - if it's an anaerobic, alcohol tolerant, acid-loving bacteria then no.

The book Wild Brews is an interesting read on bacteria - it shows that some beer spoilers are quite specific about their tastes and only really work when the conditions are right for them.

BTW, welcome back DaaB... sorry about the mess. We'd have tidied up if we knew you were coming back.

[delboy]

Bloody alcoholic bacteria!

How about yeast washing then?

How critical do you think a ph of 2 is ? Would 1.8 knacker the yeast or will 2.2 let some of the bugs survive with a nasty rash? Could I get a pharmacist to make up a ph 1.9 solution and add it to the yeast i'm about to pitch and be reasonably certain i'm pitching a clean healthy batch ?

On a slight tangent what would our scientists/chemists use for canning jars ?

I've heard TJB suggest pickle jars (or possibly pasta sauce jars) which sound great as they are reusable and don't have a wax seal to worry about, on the other hand though i've never yet managed to get rid of the smell of vinegar or sauce from one, should this concern me, and what about the stain that can occur on the seal?

The pH scale is logarithmic so thats actually quite a big swing but i reckon you'd be fine between those points.
An acid wash would of course be useless against acidophilles like lactic acid buggers and of course wild yeasts would survive.

I'd keep an eye out on ebay for a schott duran bottle which are autoclavable.

I'd send you one but the postage would probably be a killer

[steve_flack]

what's the worst that can happen anyway!

You kill everything

[Aleman]

Steve said it all,

I've tried acid washing it its a real B*gger, when it says pH 2.0 it means it, and make sure that you follow the method to the letter.

I've noticed a massive reduction in cell viability following acid washing, so much so that I don't do it anymore. I'll reuse a yeast cake a couple of times as I've had microbiological analyses done of the worts at various stages, and I'm confident that up to three times I have no problems with contamination (I do wash the yeast cake with sterile water in between uses)

If I had a house strain and wanted to keep it in good condition then its a technique I'd have to get better at, as it is I rarely brew a beer to use the same yeast in succession, so I'll just re culture as I need to.

I use Pasta Sauce Jars for Sterile wort canning. The get washed several times in normal washing up, then they get a bloody hot soak with antiformin, and then left for a week with the antiformin, generally no smell or stain remains. The worst jars for retention of smell has to be Branston Pickle, it is practically impossible to remove that smell from the jar, but the Colemans Pasta stuff is pretty easy. I have a couple of Dolmio Jars to try and clean so I'll report on those later.

Got to say though that the proper glassware does make the operations easier.

[steve_flack]

Any suggestions for something that can be used round the house for culturing in that will fit in a pressure cooker? (anyone?)

What do you mean? Growing stuff up off of a slant? I've heard baby food jars work - Pesto jars are quite small as well. Myself I'd use a glass universal sample jar...I have them in the house but I guess most folks don't.

[delboy]

I've heard baby food jars work - Pesto jars are quite small as well.

Yep, that's the kind of thing I meant, I was figuring a 1L lab flask would be a little too big. I guess those Steralin tubes would wither and die in a pressure cooker.

Looks like its pasta and baby food for dinner then DaaB.
The wee sterilin bottles come sterilised (U.V.) i think so no need to bung them in the pressure cooker.

From what TJB says it seems acid washing yeast in a home setup isn't that easy but if you do decide to give it a bash apparently its best to do it with phosphoric acid as this should in theory when decanted allow you to pitch into wort and have the least flavour impact.

[delboy]

I know you aren't fishing for freebies but if you want i'll send you some sterile syringes and sterile filters (remove all the bugs and viruses). These are ideal for making up small volumes of completely sterile wort.
Oh and they don't weight that much

[delboy]

Cheers Del, I have plenty of sets of Corni seals so I can return the favour. Can I stick them in the pressure cooker for future use ?

To be honest they are meant to be disposable, so i don't know if they would survive the autoclaving process i suppose it would be a case of suck it and see.
They are ideal for sterilising small volumes if for instane you need something quck or can't be arsed firing up the pressure cooker.

[Madbrewer]

Infection risks aside, I do like the idea in principle .....

On another note ... I think 'my' method of yeast propagation could lend itself to creating an 'infection' as I don't understand enough about lab procedures. In short I use a milk bottle, and a simple few tablesoons of extract boiled in half a pint of water, cooled, transferred via sanitised funnel into sanitised bottle with the small amount of yeasties in. Air lock inserted and left to get on! I am scared that the air will carry microbes, that the sanitising is not 'sterile' enough & somehow just transferring it into the brew after removing the bung and wiping the bottle neck with alchohol isn't enough.

If Delboys got a 'library' of yeasts though - I'm quite envious.

Also regarding the small PET bottle in the fridge for storage technique, how long can you yeast be used for after the bottling date?

[delboy]

Infection risks aside, I do like the idea in principle .....

On another note ... I think 'my' method of yeast propagation could lend itself to creating an 'infection' as I don't understand enough about lab procedures. In short I use a milk bottle, and a simple few tablesoons of extract boiled in half a pint of water, cooled, transferred via sanitised funnel into sanitised bottle with the small amount of yeasties in. Air lock inserted and left to get on! I am scared that the air will carry microbes, that the sanitising is not 'sterile' enough & somehow just transferring it into the brew after removing the bung and wiping the bottle neck with alchohol isn't enough.

If Delboys got a 'library' of yeasts though - I'm quite envious.

Also regarding the small PET bottle in the fridge for storage technique, how long can you yeast be used for after the bottling date?

Madbrewer if you can buy a conical flask (pyrex) then you can boil the extract in that, should help prevent a lot of contamination issues.

I don't actually have a library yet im just thinking its about time i set one up