Made slants and sterile starters, questions

[USMChueston0311]

Hey guys made slants with wort/agar agar, tubes of mineral oil, and tubes of wort. Pressure cooked at 15 PSI for 20 minutes once 15 PSI was reached.

My question is the wort has particulates of DME floating and suspended in it. It didnt disolve all the way. Is this an issue? I boiled 1 liter of water, and added 70 grams of DME, stirred for awhile, and removed from heat. Its not all the way dissolved... Do i need to make new sterile starters? Or is this normal?

 

[USMChueston0311]

Here is a pic of starters sealed in test tubes

 

[ba-brewer]

That looks like break material. You can reduce the amount of break material by first boiling the wort and cooling and collect clear wort to sterilize in the test tube or using to make slants. At the high temp of the pressure canner more will form but it will be less.

I know people sterilize wort in test tubes but it made me a little nervous so I got some small 4oz mason jars for small amounts of wort.

 

[USMChueston0311]

That looks like break material. You can reduce the amount of break material by first boiling the wort and cooling and collect clear wort to sterilize in the test tube or using to make slants. At the high temp of the pressure canner more will form but it will be less.

I know people sterilize wort in test tubes but it made me a little nervous so I got some small 4oz mason jars for small amounts of wort.

so what are you saying? is it usable?

 

[ba-brewer]

I see people making sterile wort in vials so yes it should be usable. If you were planning to grow yeast in that test tube it might be hard to tell how much new yeast you have grown.

I sterilize a small vial and transfer clear sterile wort to it for the first step so I can tell how much new yeast I created.

It takes some effort to can/sterilize wort so I don't do it that often. Test tubes and vials don't seem like you can get a guaranteed air tight seal so long term stability seems questionable to me. That is why I use small mason jars, if it still has a vacuum I know it is good. Just being over cautious.
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[user 246304]

I do sterilize in test tubes, without first boiling (or sterilizing, which yields even more break) wort. Or rather, I'll boil for a few minutes, just enough for some break, let it settle, carefully pour off into a container, then pipette 10 mls into my vials. If the lids on your tubes are slightly unscrewed, you will kill anything if you're following a proper sterilization routine.

My experience is similar to ba-brewer's - it is somewhat harder to see the yeast at bottom but at least for me, the yeast is a creamy white and very different from any settled break.

If you want to boil or sterilize first, you'll end up with a clearer wort. If you don't, I personally think it's fine (and it could probably be argued that that break can provide nutrients to the young yeast).

 

[USMChueston0311]

My slants with agar and wort have bubbles
I them..... aren’t going away️. Normal?

 

[user 246304]

My slants with agar and wort have bubbles
I them..... aren’t going away️. Normal?

I've never seen that, Marine, sorry I can't help more. Did you sterilize them? Were the tops loosened?

 

[Monkey Mountain]

Should be OK. Did you use fermcap or something like that to keep the bubbles down?

 

[USMChueston0311]

Should be OK. Did you use fermcap or something like that to keep the bubbles down?

I did not. The slants are hardened this am, full of bubbles. I’ll attach a pic, and the DME has settled to the bottom of sterile wort tubes.

I shook them up as instructed after sterilization. And the bubbles never went away.

 

[USMChueston0311]

Pics, 1 is slant, full hardened, pic 2 is starters

 

[ba-brewer]

I followed the instruction in the sticky here on HBT with good results. I don't think you need to shake the slants, just tape and set on an angle to harden.
https://www.homebrewtalk.com/forum/threads/slanting-yeast-photos-and-instructions.579349/

 

[USMChueston0311]

I followed a different set and now I’m stuck with bubbles. Should I make new ones or do you think it will be ok?

 

[ba-brewer]

I would start over, not sure I could get a fiddly loop between the bubbles to the clear surface. If you think can get to the clear smooth surface then give it a try. Does not hurt to do a sample run anyways.

Also I flood the vial with wort and loosen the yeast and even with no bubbles I will occasionally get thin strips of agar agar jell to come loose. Sure it does not hurt anything but yeast will cling on to it later and it looks strange.

 

[Monkey Mountain]

Pics, 1 is slant, full hardened, pic 2 is starters

The starter is fine. The slant, like ba-brewer says, may be hard to work with if those bubbles hardened.

I usually put a few drops of Fermcap in to keep the bubbles away.
https://www.morebeer.com/search?search=fermcap

 

[USMChueston0311]

I ordered fermcap for next round of slants I do, I want to bank 12-15 strains. I read somewhere that some people are using distilled water in place of mineral oil and it can be stored at room temp
This way? Instead of the mineral oil, which usually supposedly lasts 12 months or so with no work according to this write up about an experiment with distilled and mineral oil.

I also reheated my agar slants until they liquified and am current re slanting with zero bubbles. I think it will be just fine.

 

[Monkey Mountain]

I use distilled water but store them refrigerated. I see no problems after 12 months but I am re-making them every 12 months anyway.

 

[NeoBrew]

Do you grow them up and then slant them or do you just transfer to a new slant and grow them there?

 

[Monkey Mountain]

Not sure if this is the best way but it works for me. I grow them up in 10ml of wort (in a test tube) for 2 or 3 days and then streak some plates. I let them grow on there for a few days and then try to find 10 colonies that look like they started from single cells. I put those 10 colonies into another 10ml starter and let them grow for a few days. Just in case something goes wrong, I do multiple plates and starters (2 or 3) for each yeast. I then use that for the slants.

When preparing the slant, I streak the slants and let them grow there for a few days before adding the water. To make sure everything stays sealed up good, I seal the cap with electrical tape before putting them in the refrigerator. Again, just in case, I prepare multiple slants for each yeast.