Renewing The Yeast Cultures

[newguy]

I believe that Craftbrewer is selling them for $9.80.

Edit: just checked; yes, it's Craftbrewer.

 

[Benniee]

Thought I would stick up a pic of my first slant. It's done in a baby food jar as I didn't have any tubes at the time.

I inoculated it with some US-05 yeast from a harvested slurry - I know it's a dry yeast but I wanted to test my method was sound.

To my untrained eye it seems ok. It took a while to get going as the weather has been pretty cold, and the condensation has pooled a little bit in the bottom of the jar.

The next step will be to make a starter from it, and taste test the result.

Benniee

 

[Sprungmonkey]

absolutely nothing wrong with doing it this way Benniee - just takes up a bit more room than a tube. looks good.

 

[Chad]

I tried a first run at some slants today, and based on my results I have a few questions.

1. Are you pressure cooking the wort + vial together?
2. If so, are you screwing the lid on tight? I didn't (the lid was screwed on and then back 1/4 turn) and found that the wort was bubbling back out.
3. If the lid is on tight, will the container deform, or is there an equal pressure between inside of vial and outside of vial to negate this?

 

[Zwickel]

absolutely nothing wrong with doing it this way Benniee - just takes up a bit more room than a tube. looks good.

+1 subscribe
yeah, when I was starting with yeast farming, I did it exclusively this way.
The advantage is, one can start with a bigger amount of wort, means your starter gets ready to pitch earlier.

Disadvantage is only it takes more space.

Keep on doing....Cheers :icon_cheers:

 

[braufrau]

I tried a first run at some slants today, and based on my results I have a few questions.

1. Are you pressure cooking the wort + vial together?

yep.

2. If so, are you screwing the lid on tight? I didn't (the lid was screwed on and then back 1/4 turn) and found that the wort was bubbling back out.

Nope. Just sitting it on the top. I only 1/4 filled the tube.

3. If the lid is on tight, will the container deform, or is there an equal pressure between inside of vial and outside of vial to negate this?

There is some risk .. I'm not sure how much .. that the container may implode. That is why safety instructions for an autoclave say not to have the lids one. But I think an autoclave gets higher in P &T than a pressure cooker.

 

[Sammus]

I do mine as like canning. Pressure cook the vials with the lid on, but until it only just starts to tighten. It's loose enough to let the pressure out when its hot, but as it cools it vacuums itself shut. I get shocking condensation but *shrugs*.

Only problem I'm having is plating to isolate cultures...I've been having bad trouble with infection - the same prep as I use with slants, but my petri dishes get covered in mould, and my slants stay clean *shrugs*...

 

[Benniee]

Only problem I'm having is plating to isolate cultures...I've been having bad trouble with infection - the same prep as I use with slants, but my petri dishes get covered in mould, and my slants stay clean *shrugs*...

I haven't used petri dishes yet, but some stuff I've read mentions that they're not airtight, and usually need a bit of tape to seal the two parts together and keep air out. Are the dishes growing mold after you inoculate them or just while they're sitting there as blanks?

Benniee

 

[~MikE]

Only problem I'm having is plating to isolate cultures...I've been having bad trouble with infection - the same prep as I use with slants, but my petri dishes get covered in mould, and my slants stay clean *shrugs*...

first, you need to be anal when using petri dishes, they have a much larger surface area and opening than slants and will get infected easier. make sure you're getting the pre-sterilized dishes. once you've made them up, seal them. otherwise, even if you keep them in the fridge, fungi and bacteria will find their way onto them and will grow as soon as you go to use it. when using them, be very sterile. 70% ethanol your hands and bench. work near an open flame. flame your loop (preferably till it's glowing. avoid having the petri dish open any longer than you need to. seal it up again once innoculated.

Thought I would stick up a pic of my first slant. It's done in a baby food jar as I didn't have any tubes at the time.

that's a lot of media for slantage. if you're using a larger tube/jar, you don't really need to have it slanted. slanting the media is for increasing the media's surface area in a narrow tube. i sometimes use the 30ml specimen containers (similar to urine sample containers) - enough media to cover the bottom is plenty.

hope this helps.
-mike

 

[Chad]

2. If so, are you screwing the lid on tight? I didn't (the lid was screwed on and then back 1/4 turn) and found that the wort was bubbling back out.

Just did a 2nd batch today with much better success and thought I would share. This time I put the lids on loose, and didn't have any troubles with the wort bubbling out.

My theory is that with my first batch, the lids weren't loose enough to let the gases escape fast enough, putting more pressure inside the vial, raising the temp. and making it boil violently. With the caps loose, the gas could escape and keeping everything inside the vial a bit more calm.

 

[Benniee]

Just did a 2nd batch today with much better success and thought I would share. This time I put the lids on loose, and didn't have any troubles with the wort bubbling out.

My theory is that with my first batch, the lids weren't loose enough to let the gases escape fast enough, putting more pressure inside the vial, raising the temp. and making it boil violently. With the caps loose, the gas could escape and keeping everything inside the vial a bit more calm.

So did you just open up the pressure cooker and tighten the caps once it had cooled a bit? I know that's a pretty obvious question but I'm wondering how cool you let the pressure cooker get.

Benniee

 

[Benniee]

that's a lot of media for slantage. if you're using a larger tube/jar, you don't really need to have it slanted. slanting the media is for increasing the media's surface area in a narrow tube. i sometimes use the 30ml specimen containers (similar to urine sample containers) - enough media to cover the bottom is plenty.

Yeah, I realise that tilting the jar was probably unnecessary, but I wanted to to a true test run on making up a "slant".

I've got some 30mL tubes now so my next go will be in some smaller containers.

Benniee

 

[Chad]

So did you just open up the pressure cooker and tighten the caps once it had cooled a bit? I know that's a pretty obvious question but I'm wondering how cool you let the pressure cooker get.

Once the pressure cooker was finished, the pressure was released immediately and opened. The caps on the vials were then done up tight.

 

[mckenry]

Just thought I'd let all know about my latest reculture. I had a Wyeast 1084 Irish Ale. Cant even remember when I bought it, though it would be late 07 or early 08.
I took a vial from a brew in oct 08 and it has been sitting in my bar fridge since.
So, here's my method of reculturing for beginners, which is so simple.

Day 1 I took the sample out of the fridge to warm to room temp. Same time I boiled 50g of DLME in 500mL water for 10mins then put in a flask in a fridge (had a lid, but you could use glad wrap)

Day 2 Took the DLME mix out of the fridge and let it come to room temp. When room temp achieved, mixed the two and shake vigerously and insert bung and airlock. Swirl whenever I think of it.

Day 3 High krausen achieved and bubbling slowing. Made another starter - this time 100g in 1L water and same process followed.

Day 4 Poured off excess liquid, leaving yeast layer at the bottom. Smelt and tasted the liquid. No problem there. Mixed the latest DLME starter with the yeast and shaked vigerously etc.

Day 5 High krausen achieved and let to settle right out. Read about best to leave for 18 hours after fermentation, to build up food reserves.

Day 6 Pitched to 1.065 wort. 12 hours later the fermentation is in full swing at a temp controlled 19C.

Easy.

 

[mckenry]

Just thought I'd let all know about my latest reculture. I had a Wyeast 1084 Irish Ale. Cant even remember when I bought it, though it would be late 07 or early 08.
I took a vial from a brew in oct 08 and it has been sitting in my bar fridge since.
So, here's my method of reculturing for beginners, which is so simple.

Day 1 I took the sample out of the fridge to warm to room temp. Same time I boiled 50g of DLME in 500mL water for 10mins then put in a flask in a fridge (had a lid, but you could use glad wrap)

Day 2 Took the DLME mix out of the fridge and let it come to room temp. When room temp achieved, mixed the two and shake vigerously and insert bung and airlock. Swirl whenever I think of it.

Day 3 High krausen achieved and bubbling slowing. Made another starter - this time 100g in 1L water and same process followed.

Day 4 Poured off excess liquid, leaving yeast layer at the bottom. Smelt and tasted the liquid. No problem there. Mixed the latest DLME starter with the yeast and shaked vigerously etc.

Day 5 High krausen achieved and let to settle right out. Read about best to leave for 18 hours after fermentation, to build up food reserves.

Day 6 Pitched to 1.065 wort. 12 hours later the fermentation is in full swing at a temp controlled 19C.

Easy.

Weird - I went looking for a thread like this to let other brewers know about my latest culture and find myself as the last poster, more than 18 months ago.
Turns out the yeast strain is the same one!
Which means this particular strain is 4 years old and only been used a handful of times.
I made a robust porter wort a while back, no chilled. The cubes have been in the garage for a while now. Decided it was time to brew them for next winter.
[These days my method is slightly different to the above. I now own a 5L flask & a stir plate and I get my starters as drainings from my MT]
I grabbed the vials from my bar fridge - dated Jan 2010.
Boiled 4L of starter from my robust porter, directly in flask.
When temps met up, pitched the contents of the vials, and plonked on the stir plate for 24 hours.
No visible signs of krausen after another 24 hours, so just let nature do its thing.
The yeast layer at the bottom was growing every day, so I wasnt worried.
After 6 days I took the SG. Had gone from 1.040 to 1.008, so I pitched it after pouring off the liquid.
After one week in the PV the krausen ring has subsided, but evidence shows 150mm of krausen at some stage.
Glad wrap is still straining to burst, so its still fermenting.
Just goes to show that you can store for a long time and renewing the cultures, while it will keep the viable cell count up, isnt as necessary as some will have you believe.
Everything is going well, sample is good.

Note - all I ever do is grab some sludge from the bottom of the PV, into a few 50mL vials.

mckenry