recurring contam in WBS
Posted 30 September 2008 - 02:50 PM
I tried WBS and cake for my first experiments some months ago. had a huge success with both. colonized WBS lasted a long time with many G2G.... Then I stopped experimenting for a while.
I just came back on hobby and tryed to make some new WBS.
I had 3 times consecutively the same contamination problem. this is the one pictured on photos.
This is accompagned with a very bad odour. don't have the words in english to describe you..
My entire process is very clean. the grain are prepared like the doc's WBS tek. I PC for 90 mn.
Inoculation in a homemade still air glovebox, loaded with isopropyl alcohol ....
I use the lid shown. A blob of silicone for inject port, and a layer of Tyvek for breathing via the hole (2 would be better ?).
I used exactly the same methods for my first attempts...
Any Idea about the kind of contamination there ? (IMO its kind of bacterial thingy)
Any guess about how to get ride of it ?
maybe should I raise the Pcing time ? (classic food PC )
Can this come from too wet grains ? (I have some problem correctly drying them, after simmering).
Many thanks for your answers :bow:
(apologies for my poor english)
Posted 30 September 2008 - 03:31 PM
i'd just drill 1/4 inch hole in new lid stuff the polyfil in. knock up jar threw same hole. be sure to use alcohol on the needle too.
Posted 30 September 2008 - 03:36 PM
I'd suggest checking out lazlo's wbs tek. http://mycotopia.net...-technique.html
Also how much spore solution did you inject into your jars?
Posted 30 September 2008 - 06:06 PM
I'm quite greedy by now. these are bought spores... :)
I tried LC a few times but without success, I will try again..
should I raise my PCing time ? as it is a food pressure cooker (big nice one) but I don't have a clue about it's pressure level.
This also remind me of something, I have made some spores syringues from my first culture. from a mush hat that I let drop spores in a glass.
Then putting distilled water and sucking it into the syringues. (under "home" sterile procedure)
I made 3 of them, fully loaded with spores ( black everywhere)
I shooted many cakes and grains with these, but not any ever showed signs of colonization (not even contams).
how is this possible ?
Posted 30 September 2008 - 06:18 PM
Posted 30 September 2008 - 07:27 PM
Does it have a wobbler on it?
If not you should know what pressure you're using.
15 psi is the proper pressure to do any sterilizing.
Posted 01 October 2008 - 10:08 AM
but there is strictly nothing referenced about the in-use pressure, not on the wobbler or the manual or even on manufacturer's website...
Thanks to everyone for your answers. I will totally dry the exterior of the grain next time.
I'll keep you updated with my next attempt
Posted 04 October 2008 - 05:05 AM
But I was away while soaking, so instead of 1 h as you recommended me Eatyualive, time was of 3 h.
I let it drain for around 12h, frequently shaking the strainer, to move the WBS. After that time, it seemed not sufficiently dry for me, so I tryed to absorb the maximum humidity with absorbing paper..
I PCed them for 105 mn.
And here is what they look like once cool.
I feel not safe to innoc them, as they look quite too wet.
I think i'm overdoing the soaking... shouldn't the grains be at " full water holding capacity" ? in my case, I can easily mash the grain beetween my fingers ....
what do you guys think ?
Again thanks a lot for your answers, and sorry for my english...:bow:
Posted 04 October 2008 - 06:32 AM
But, there's really only one way to find out. That batch looks like it should be ok. You soaked it, but then didn't cook it? Just drained and put it it the jars?
Posted 04 October 2008 - 07:03 AM
Anyway, I will try to innoc them and see what happens. If wet spot again, i'll know what to do.
Thanks to you people. but on this case only training & experiment can solve my problem..
Posted 04 October 2008 - 07:10 AM
But you are right that practice is the answer- good luck!
Posted 04 October 2008 - 02:58 PM
I also think that livewire420 is right about using polyfill instead of tyvek.
I have found that for me, the best way to do WBS is to just load the dry seed with the right amount of water and a little gypsum into the jars, then sterilize at 15psi for 105 minutes. I have had 100% success, zero contams, for years, hundreds of jars. The seed/water ratio I use is: 1 part by volume seed/.5 part by volume water. So if I'm using 250 ml. of WBS, I put 125 ml. of water. I usually use about 3 ml. powdered gypsum per quart. I tried doing the presoak methods long ago and couldn't get good consistent results.
On the failure of your spore syringes, I think that was bacteria in the jars that you didn't detect. Some bacteria that contaminate jars is hard to detect visually, but will prevent or retard spore germination. Your syringes were probably fine, but your jars were bacterial. I've seen folks go crazy trying to figure out what's wrong with their spores, and then it turned out to be almost invisible bacterial contam in the jars that was the problem.
- Dabluebonic likes this