Slanting yeast

interesting link, if it's reliable information then it seems a microwave is perfect.

This is a GREAT thread. I have Wyeast 1469 Yorkshire fermenting right now, and this is a wonderful way to have this yeast all-year round!

So a question about taking this a step further:

Would there be a way to freeze these innoculated vials? I know 12-18 Months is pretty decent storage time, but is there a way?

In that study did they test any liquids or just bac. decontamination on the surface of objects?

ekjohns said:

In that study did they test any liquids or just bac. decontamination on the surface of objects?

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From the front page of the article:

RESULTS: The study indicated that microwave irradiation provided effective and efficient sterilization of all materials tested. Of the bacteria studied, only E coli survived beyond 30 seconds of microwave exposure. Yeast did not survive beyond 15 seconds of microwave exposure. Swabs and gauze contaminated with bacteria or yeast were completely sterilized after 30 seconds. After three minutes in the microwave oven, powdered, prepared media was free of contamination while able to support growth when inoculated with S. aureus.

Just ordered my stuff for slanting! This is gonna be fun. The only thing I still need is the agar. Any good places on line to get it? Any specific brand or type you guys recommend?

emribecky said:

Would there be a way to freeze these innoculated vials? I know 12-18 Months is pretty decent storage time, but is there a way?

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Nope that's a totally different technique:

https://www.homebrewtalk.com/f13/guide-making-frozen-yeast-bank-35891/

DrawTap88 said:

Just ordered my stuff for slanting! This is gonna be fun. The only thing I still need is the agar. Any good places on line to get it? Any specific brand or type you guys recommend?

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I got mine from Cynmar. It's expensive, but if you keep it dry it should keep for several years.

When I started out I used agar I found in the Asian section of a large local grocery store. That also worked fine.

What do you think of this pressure cooker/canner.

I have the 32 quart version of that pressure cooker. It'll work fine for sterilizing your gear.

Got a couple more quick questions.

1) What type of water are you using in the pressure cooker/canner to create the steam? Distilled, RO, Tap?

2) Are you letting that water come in contact with the bottoms of any of the glassware that you are sterilizing?

I put my vials into pyrex measuring cups. The cups rested on a large crumpled piece of aluminum foil.

I used tap water.

Just read this whole thread Thanks! Looks like i need to get some agar, stir plate,and some vials i already have everything else including a 12q pressure cooker i use for making canned stews and Pate.. I cant wait!

RO water is best (inside the pressure cooker) so it won't scale your pot. Tap water is probably the best choice to prepare the media so the yeast can get the calcium they need from the water.

In the cooker, I place my vials inside pint jars to keep them upright during cooking. Make sure you use a false bottom in the pressure cooker or some means to keep the jars off of the bottom or they may crack.

Sweet i have RO water my pressure cooker came with a false bottom and i have plenty of tap water.. now to get the agar stuff and the vials and stir plate..
Then i am set...
Thanks again!

Saccharomyces said:

RO water is best (inside the pressure cooker) so it won't scale your pot. Tap water is probably the best choice to prepare the media so the yeast can get the calcium they need from the water.

In the cooker, I place my vials inside pint jars to keep them upright during cooking. Make sure you use a false bottom in the pressure cooker or some means to keep the jars off of the bottom or they may crack.

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Is the pressure cooker really the only way? I can't convince my SWMBO to get one right now.

Could I bake the vials at 250F?

Great tutorial!

Groo said:

Is the pressure cooker really the only way? I can't convince my SWMBO to get one right now.

Could I bake the vials at 250F?

Great tutorial!

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There's a link somewhere in this thread about microwaving your stuff, but it's not proved to work 100%. You could bake the vials, but the temp is much higher and takes hours instead of minutes like with a pressure cooker.

Since SWMBO isn't on board right now, see if you can get one really cheap from craigslist or find someone in your area that has one for you to borrow.

DrawTap88 said:

There's a link somewhere in this thread about microwaving your stuff, but it's not proved to work 100%. You could bake the vials, but the temp is much higher and takes hours instead of minutes like with a pressure cooker.

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I would use the microwave method for plates, but not slants, if there is any contamination on a plate it will be easy to see and obvious, in a slant, not so much. (Also the life expectancy of a plate is weeks, not months or years..)

Baking won't work any better than a microwave, no matter how hot, because you still can't make water boil over 212 at atmospheric pressure.

yep, an oven may work for sterilizing dry plates, tubes, etc, but it won't work if you are trying to sterilize liquid media.

Any opinions on those ultrasonic cleaners? Harbor Freight just sent me a coupon where I can get this thing for $22... Seems to good to be true but hey it's worth asking...

http://www.harborfreight.com/ultrasonic-cleaner-3305.html

are you asking about sterilizing? Because that just cleans... so no, it can't be used for sterilizing stuff for slanting

I believe the ultrasonic cleaning machine will provide agitation for cleaning, but it will not sanitize or sterilize. To do this, you really need to sterilize your equipment and medium.

To get the agar into the slant I use a syringe instead of a funnel, which works quite well. It's safer because you don't have to pour boiling hot liquid and they have measurements on the side so you can put the same amount in each.

Has anyone tried using an Ionizer to help clean the air when working with your plates/slants? (Like this one: http://www.amazon.com/dp/B004FGNTYE/?tag=skimlinks_replacement-20)

I too have been using a syringe for transfering 10ml, or less, of liquids and agar solutions into vials. Quick, easy and convenient.

Hello,

I just made my first slants. I have worked with agar before but never with beer yeast.

When the vials cool and set there is a tiny amount of water that stays on the surface. I inoculated on saturday and I am seeing healthy growth. I am presuming this tiny bit of water is sterile and I should not worry about it.

Any thoughts or experiences?

Yeah I wouldn't worry about the condensation, should be fine. Next time you can get rid of that by leaving the caps loose for a few days to dry out the slants after they cool, as long as they are in a draft free place and are not disturbed prior to capping they will dry out slightly and remain sterile.

I do not have a pressure cooker

Are there any other methods of sterilization that might get by ok?

Could I just use a large pasta pot to put the items in and then boil the guts out of it with the glass lid held on tightly for about 15 mins?

I really would like to try this but SWMBO might think I am going too far buying a pressure cooker. Unless perhaps I could buy her one for her birthday

el_caro said:

I really would like to try this but SWMBO might think I am going too far buying a pressure cooker. Unless perhaps I could buy her one for her birthday

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There is a method you can use to sterilize media without a pressure cooker.

Day 1: Prepare the tubes and heat using a boiling water bath for 30 minutes. After they cool, store the tubes in a warm box - around 90*F - you can use a heating pad or aquarium heater.
Day 2: Repeat.
Day 3: Repeat.

The idea is any spores that survive the previous boil will activate when the media is at 90*F, reproduce, and the next boil will kill them. After you have done this a few times the population is low enough the chances of contamination are sufficiently low the media can be used.

Sounds like a lot of work to me. A pressure cooker has other uses besides sterilizing media. I use it to make my own chicken stock in jars using leftover chicken bones that would otherwise be thrown away. If you watch Ebay and Craigslist you can probably snag one for $30.

Saccharomyces said:

Sounds like a lot of work to me.

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Seconded. Working pure culture with a pressure cooker can be frustrating enough. I think any attempt to get pure media without a pressure cooker is going to just discourage you.

So.. learn how to pressure cook a chicken (simple), convince SWMBO she must have this wonderful, juicy, quick cooking chicken. Cook dinner a few nights, and she may never realize why you actually bought it. Win

Thanks for the tips guys. Pity my wife is a vegetarian.

I will keep my eyes open for a cheap pressure cooker.

el_caro said:

Thanks for the tips guys. Pity my wife is a vegetarian.

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Tell her you want to start canning vegetables.

actually vegetarians love pressure cookers cause you can steam veggies quickly while keeping all the good nuetrients. Have her look into some veggie recieps and i better after a night of looking she will want one

Going to buy her one tomorrow. 8.5L is on special and that should be big enough for her veggies.

Disaster adverted. Missed the part about not sealing the lid on the slant tube after inoculation and for whatever reason didn't think about CO2 production. Just cracked the caps of the tubes and got a nice puff of CO2.

Wonder how much pressure these little guys will hold? Anyone had a slant bomb?

JasonInBTR said:

Wonder how much pressure these little guys will hold? Anyone had a slant bomb?

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They will hold alot... actually some people like myself prefer to keep them sealed for 24 hours after innoculation, then its useful to check for fermentation activity via pressure. I'd also rather keep them in the safe sealed enviroment when at such low population, then only once they are actively growing will I let in air and get stir plate going, etc.
I've forgotten about them before and when I finally cracked them, they foamed over immediately and violently but did not break (speaking of 10ml liquid starters).

If you guys use amazon a lot with amazon prime, i got a bunch of agar powder delivered in 2 days.

http://www.amazon.com/gp/product/B001EQ5I6U

subscribed

JUST DO IT!!! I'm in 10 strains and 1 bac. and haven't regretaed it yet.

krops13 said:

JUST DO IT!!! I'm in 10 strains and 1 bac. and haven't regretaed it yet.

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What bacteria do you have and did you have to do anything different?

Thanks for the write up Sacc. I have some White Labs and Wyeast on the way and I'm interested in starting up some slants but dont have all the equipment.

Is it possible to store a little of each yeast in a sanitised vial in the fridge until I get the equipment necessary to start making slants?
If so how much would you save in each vial?
Would you save the yeast directly from the Vial/Smack Pack or would you save it from the starter?
How long do I have for the yeast to remain healthy in the fridge before I would need to slant?

Thanks again for the help!