|
mushes
Stranger
Registered: 02/24/20
Posts: 23
Last seen: 2 years, 4 months
|
What did I do wrong with these oysters?
#26502034 - 02/24/20 06:07 PM (3 years, 10 months ago) |
|
|
Hi, I am mushes. I have lurked this forum and appreciate the knowledge that has been shared over the years. Recently I ran into a problem which cost me quite a bit of time and frustration and was hoping someone out there might able to share some insight:
I have some experience and have had good success cultivating and fruiting a variety of gourmet species on a small scale in a 4-tier greenhouse in my bathroom. I decided to do a larger scale trial of Pleurotus citrinopileatus because the ambient temperature in the room I wanted to grow in was good (I have never grown in this room before). My plan was to grow in a sealed greenhouse with FAE through the greenhouse vents + a humidifier inside. The grow room was about 2.5m squared. Ideally, I would have had ~100 blocks fruiting in this tent as a source of additional income.
I made up some rye spawn from LC with my autoclave / flow hood (I have produced many bags of clean grain spawn successfully). In the past, I have pasteurised substrates in a pillow case in my PC, with good results. This time I pasteurised 50/50 bulk straw and sawdust / fine woodchips in a 200 litre drum at 160F/71^C for 2 hours, then pulleyed the mix out of the drum and drained. I didn't have a big table handy so I laid a clean plastic sheet down on the ground (was this my mistake!?) and dumped the bulk substrate onto it, and mixed in spawn at 1:10 ratio when the temperature of the bulk dropped.
Whilst wearing clean clothes, gloves sanitised by alcohol, I packed filter patch bags with the mix using a sanitised juice bottle cut in half. When the bags were full, I wiped with tissue so that it was clean around the top and then sealed, first batch by zip tie, second by impulse sealer.
I made one batch with half a barrel full of substrate (25 bags), when it appeared to be colonising well a week later I made another batch of 23 bags with the same method. I came back a week later and ALL the bags were infested with Trichoderma! I could smell it from 20 metres away! So, I had the soul crushing job of dumping them all. On the bright side, the bags were sealed so they are unlikely to have sporulated in the room.
The air is quite dusty in the shed this work was carried out in (grain spawn was made in a different location) and the shed is situated in a valley with a high spore load where moulds, mildew and lichens grow. I was attempting a low-tech grow with just the greenhouse + humidifier in a sealed room of the shed.
Whilst making the mix on the ground was not the best idea, I am surprised at the 100% rate of contamination and I am wondering if it is even worth further effort attempting to cultivate in this shed given the conditions. Does anyone identify issues with the method that i didn't notice?
Thanks all who took the time to read this, I greatly appreciate feedback
|
seagu

Registered: 03/03/18
Posts: 952
Last seen: 8 days, 12 hours
|
Re: What did I do wrong with these oysters? [Re: mushes]
#26502291 - 02/24/20 08:41 PM (3 years, 10 months ago) |
|
|
Heyas, Well, since you been growing awhile and all that, you probably know Meanie Greenie can rear its ugly head through all sorts of ways and that you mentioned a bunch of different ways it could have came around. Bad LC that was previously clean. I have seen this happen and have total nuclear meltdown like you describe. I don't use LC no more. I go with agar and petri dishes. Is that what happened in your case? But that is my first thought.
My 2nd thought is this: I have an aquarium that had some fish in it that died. I drained everything cleaned most everything, but I didn't bleach the tank so while it looks clean it hasn't been sterilized yet. I have done a lot of filter patch bags in there because I needed space that the cats couldn't get to. Most all bags I have held in there have contaminated. I figured it was just luck of the draw and some bad stuff I needed to just get a clean culture out of. I finally did and didn't use the tank again to hold anything and have had zero mold issues. The other week I decided to put two bags in there and 1 contaminated.. So, the point of the story is to your questions about your space.. maybe..
hope some of this helps
-------------------- Plan to win or you are planning for failure. Don't let anyone tell you you can't do it. Just figure out the solution. Even if that means banging your head on a wall until the solution oozes out of you.
|
mushes
Stranger
Registered: 02/24/20
Posts: 23
Last seen: 2 years, 4 months
|
Re: What did I do wrong with these oysters? [Re: mushes]
#26502368 - 02/24/20 10:00 PM (3 years, 10 months ago) |
|
|
thanks for your input 
There is a small possibility that the LC is dirty, but the grain spawn I made from it appears clean and colonises fully with no signs of contamination.
I'm fairly sure this occured because the environment I transferred the spawn to substrate in is full of mold...
|
trout
Flyfisherman



Registered: 12/11/07
Posts: 536
Last seen: 3 days, 8 hours
|
Re: What did I do wrong with these oysters? [Re: mushes]
#26507289 - 02/27/20 09:26 PM (3 years, 10 months ago) |
|
|
Are you sure your pasteurization temps were correct. That large of a batch might not have heated up all the way through. Typically oysters will mostly out run tric if properly pasteurized. Also the mix could have been too wet and not enough fae in your bags but that typically leads to bacteria.
-------------------- I need tropical cultures, ABM, V.v....!!!! Well things don't always look as they are and things can be misread and mistaken for what they realy are so don't read too much into what I say since I might be mistaken myself. And remember I rarely ever give a definate answer.
|
wildernessjunkie
Reshitivest


Registered: 06/13/10
Posts: 8,118
Loc: HTTP 404 Not Found
|
Re: What did I do wrong with these oysters? [Re: trout]
#26507550 - 02/28/20 02:17 AM (3 years, 10 months ago) |
|
|
I would suspect the spawn first, and then the processing of the substrate second.
|
DigitalRhizae
Stranger



Registered: 06/03/17
Posts: 352
Last seen: 1 year, 8 months
|
|
What trout and wildernessjunkie said. If your spawn was clean the likely contamination vector was probably with your pasteurizing process. Either you didn't fully bring the entire bulk up to the pasteurization temperatures for long enough or you over pasteurized the bulk at higher temperatures and the trichoderma got a foothold before the oysters. If your spawn is fully colonized and clean and you've pasteurize your substrate fully you should be able to inoculat in fairly dirty areas. I've done this in a very dusty basement and I know a lot of trichoderma spores are present because of the many times I've left fruit and garbage for to long and it has rotted and left spore loads in the air.
|
mushes
Stranger
Registered: 02/24/20
Posts: 23
Last seen: 2 years, 4 months
|
Re: What did I do wrong with these oysters? [Re: DigitalRhizae]
#26517589 - 03/04/20 10:07 PM (3 years, 10 months ago) |
|
|
Thanks for the suggestions 
I am quite confident the spawn was clean.
The water used to pasteurise was from a dam, I realise I did not boil the water prior to pasteurising, which I should have done.
I pasteurised at 160F / 71C for 2 hours, does this seem sufficient or would it be better to go for longer?
I am going to try a smaller batch again with boiling the water first, possibly pasteurising for longer, evaporating on a table once dripping stops to lower moisture content and using 50% more spawn.
|
DigitalRhizae
Stranger



Registered: 06/03/17
Posts: 352
Last seen: 1 year, 8 months
|
Re: What did I do wrong with these oysters? [Re: mushes]
#26521402 - 03/06/20 10:10 PM (3 years, 10 months ago) |
|
|
I believe 2 hours is too long. If I recall correctly pasteurization time is 60-90 minutes. But I think the temperature is more important. How clean was your straw? Was there any flower heads that may have contained grains? Also are you sure the very middle of the substrate got to the proper temperature for the required amount of time?
|
mushes
Stranger
Registered: 02/24/20
Posts: 23
Last seen: 2 years, 4 months
|
Re: What did I do wrong with these oysters? [Re: DigitalRhizae]
#26630420 - 04/26/20 05:34 PM (3 years, 8 months ago) |
|
|
Hi guys, I have tried again with your suggestions and am having good success now, fruiting many kgs!
For anyone with similar issues who is wondering what I changed:
2h pasteurisation was definitely too long! I am now running it for 1h between 80-71 Celsius (dropping the substrate in at 80 C).
I boil the suspect water and let it cool to 80C first now. (I have not done a trial to see whether this is necessary. At this stage I assume it is. The cost of gas is negligible compared to the loss of a batch if it is indeed a necessary step)
I also have a table which allows me to elevate the substrate when I spawn it.
I also replaced the dirty old hemp rope on my pulley system which was fraying off dirty fibres into the pasteurised substrate when I pulleyed it out to drain.
Have not had a block contam on me since making these changes! good luck people
mushes
|
brindle foxx
Doing it my way



Registered: 11/11/18
Posts: 420
|
Re: What did I do wrong with these oysters? [Re: mushes]
#26630806 - 04/26/20 09:18 PM (3 years, 8 months ago) |
|
|
How long will Oyster last in cardboard/ paper bag in a fridge for storage ?
|
mushes
Stranger
Registered: 02/24/20
Posts: 23
Last seen: 2 years, 4 months
|
Re: What did I do wrong with these oysters? [Re: brindle foxx]
#26631140 - 04/27/20 12:52 AM (3 years, 8 months ago) |
|
|
I can grow them but I'm not the most experienced. Hopefully someone else will share some knowledge.
IME they become unsellable quickly - 2 days max in the fridge if you intend to sell them.
If you don't care about how they look they are still fine to eat after 4-5 days in the fridge.
|
|