Trav suggested I put up some teks of how I do my mush, so, well here it begins.

I plan on putting a few seperate teks and splitting them up with as many pictures as I can take to help explain it as thorough as possible (I know we all love pics). Before starting, I must say that I have learned almost all of this at the shroomery (along with some help from Paul Stamets TMC, and RR's dvd Let's Grow Mushrooms!). The majority of this tek is from Let's Grow Mushrooms! (Purchase "Let's Grow Mushrooms!". I am quite new to mycology as is so I may be doing somethings wrong (which I hope that someone more experienced would point out!). This is just how I do things, I'm here to learn so if you have any tips or advice please spread the wealth!

Pasteurization = Heat treatment applied to a Substrate to destroy unwanted organisms but keeping favourable ones alive. The temperature range is 60°C to 80°C(140°F-175°F). The treatment is very different from Sterilization, which aims at destroying all organisms in the Substrate (Shroomery glossary).

Sterilization = Completely destroying all micro organisms present, by heat(autoclave, pressure cooker) or chemicals. Spawn Substrate always has to be sterilized prior to Inoculation (Shroomery glossary).

Whether to pasteurize or sterilize your horse manure is debatable. Proponents of pasteurization say that if you sterilize your horse poo, the horse poo is more susceptible to the contaminant Trichoderma (aka green mold) and that it kills the beneficial bacteria. I pasteurize.

This first tek is how I pasteurize my horse manure substrate for my rye seed spawn. Here it goes...

Step 1. Get some Horse manure.
I live in Oklahoma so we have lots of horse pastures here. All I did was go to a small family owned farm with a plastic bin and latex gloves and ask the owner if I could have some horse manure for composting a garden (not only did he say this was fine, he told me I could come by whenever I wanted). This is MUCH EASIER than you think. They won't to get rid of the horse poo anyways. So, not only are you getting free and amazing substrate, you are helping them out (this is assuming they don't sell their compost which is rare). If you live in a city with no horse pastures, I'm not sure what to tell you. You can use cow manure but horse manure is better. You can order manure some places but you lose the benefit of FREE substrate.




Step 2. Leech your Horse Manure.
If you can get horse manure that is dry (it cracks when you squeeze it and has NO shit smell whatsoever), then you don't have to leech the poo yourself--as it has already been leeched. Leeching is getting rid of the ammonia in the fresh poo. When you get your horse manure, it will be in little 2 inch balls (it's really interesting looking imo). You want to break these up and make a soil like medium. My poo was moist but did not smell like shit when I got it so most of it had been leeched, but to make sure I put it on a black trash bag that I ripped, spread it on my car garage roof, sprayed it with water, let it dry out, sprayed it with water, let it dry out, etc. I did this for a week. The poo should smell like soil (again it should not smell like POO at all). It is getting cold out here so it didn't full dry, but it is fine since it was fully leeched and I would be adding water anyways. I threw some leeched horse poo on a tub lid and brought inside.




Step 3. Mix your Horse Manure with Vermiculite and Gypsum
Here is what I start with.



Verti Lome Vermiculte (big chunks)
Purchase Verti Lome Vermiculite





Lawn and Garden Gypsum (powder)
Purchase Lawn and Garden Gypsum



I get out my big home-made strainer (which is wire mesh secured to 4 pieces of pvc pipe with 4 corner fittings with small zip ties and covered with tape to try to prevent myself from poking my hands).



I throw my leeched horse poo onto it.



I eyeball and add about 5%-10% by volume gypsum.



I mix that up dry (it's harder to mix the gypsum in when its wet).



I then mix my chunky vermiculite in a seperate bowl (the verm sucks up the water better when soaked by itself prior to adding to horse manure + gypsum).

Dry verm.



Wetted verm.



I add about 10%-20% by volume wetted verm.



I mix that thoroughly.



Then I add water and soak the horse manure.



Wetted horse manure/10% vermiculite/5% gypsum.



Mixed.



You want the horse manure soaked to field capacity. Field capacity is when you pick up a handful and no water drips out.



Then when you squeeze lightly a few drops come out.



Then when you squeeze hard the water pours out and stops after a few seconds.




Step 4. Load jars up.
I use wide mouth quart jars with foil lids.



Loosely fill jar.




Step 5. Heat jars up.
Put jars in big pot. I use my AA921 pressure cooker with the lid off. I also put the lid rings, 2 layers, with 2 layers of heavy foil above them in the bottom so the jars are not directly touching the metal.



I add cold water (you want to use cold water as opposed to hot water so the jars heat up at the same time the water heats up) so the jars are 2/3's submerged in the water.



I put a metal diveder above the jars with a brick on top to weight them down (unnecessary but I just do it). I stick a meat thermometer through the foil of the middle one so it takes the temp of the horse manure in the center of the jar.



Turn on the heat on high.



When the thermometer reaches 140 Farenheit, I turn the heat off.



They will continue to heat up until they reach 170 Farenheit, and will sit at 170 for an hour or so.



I let them cool down, remove them from water and pressure cooker, and then add to trays. I will make another thread showing how I do this sometime.

Thats it. Once combined with your spawn of choice (I use rye), this is what you can get.

cool, SWIM has recently been interested in mycology but needs a little more space in his shared apartment (or just is not ambitious to try atm)

But once he decides to start he will DEFINATELY start by reviewing this thread.

Thanks

This is something I tried today too. It seemed to work fine. Instead of using quart jars (which one should have extras but if you don't..) you can use Oven Baking Bags to pasteurize in. I like the jars because the temps throughout all of the jars pretty much stay the same. With the oven bags, the outside gets hotter earlier than the inside (obvious) so one must mix the bag while hot and put back in water. Some people throw the bags in the oven to bake as opposed to submerge in water, I don't know, I like the water better. It's easier to check the thermomemter and I think it gives more accurate readings when the entire thermometer isn't in the heat (could be wrong, I don't know). But, just to show..


Step 4. Double bag and load in Oven bags.



I use 2 Renolds Large oven bags.




Step 5. Submerge bag with horse poo in water and turn on heat.
I stick the thermometer INSIDE the bag and then wrap the bag around it so no water gets in. I make it so you can see the temp.





I checked the temps on the side and when the center was 140 Farenheit, the sides were at 160. So I took the bag out and mixed with pot holders. I then check the temps throughout and they were all around 150. I dropped back in water and it slowly rose to 170 and stayed there for roughly and hour. It is now cooling.

Again, I prefer the jars over the bag. The jars are easier and work better, but here is another method if you choose to not do jars.

gotta bump this one, very simple and thorough explanation on hpoo

I can confirm sterilised hpoo is prone to green mold. This happenned once to all my jars that contained sterilised manure. I am pasteurizing it since.

I tried different methods of pasteurization but will probably stick with the oven method a it seems to provide cleanest, least equipment and least loss of nutrients.

Jar method: For me it takes ages for the substrate to get thoroughly pasteurized when in glass jars. When the temperature inside finally reaches the pasteurization temp. (takes almost 2 hours) the outside is already overpasteurized as it is in contact with very hot water. Even when carefully controlling water temperature, the outside gets inevitably overpasteurized while the inside has not even reached the p. temperature.

Pillowcase method: Immersing a pillowcase loaded with hpoo to hot water. This provides more even heating but I think one loses nutrients and gypsum when straining the excess water (maybe the removed nutrients are not that important for the mushroom). One advantage is always having perfect field capacity.

Oven method: I will probably use a large tray loaded with the bulk substrate and candy/meat thermometer stuck in it. Then turn off the oven when inside of the substrate reaches pasteurization temp and let the oven slowly cool down. Maybe I will put an alu foil over the substrate so it cools down more slowly and prevent drying.

Pillowcase method is effective super simple .
Use a cooler to Keep the heat stable .
It works

Thanks. I will try that next time. I can get only horse manure pellets (processed and compressed) which dissolve in water leaving very little solids behind, so I was afraid most of the goods from the hpoo get flushed away. But hopefully the pillow will hold most of it.

I put the closed monotub in the oven at low heat and bake it until the internal temp reaches 155F (using a digital meat thermometer probe). Once the temp gets below 90F I quickly mix the grains in.

Disclaimer: No meelting issues for me so far but watch out the first time you do it if you decide to try this. Recommend preheating the oven well to avoid intense heat at the beginning. I also put the tub on a stone pizza baking sheet.

Plastic tub in the oven ? Sounds risky to me .

Agreed, hence the warnings.

I use sterilite tubs. They are made with polypropylene (starts melting at 320F) and/or polyethylene (can start meeting at 240F). I set the oven at 180F amd make sure it is preheated and the tub rests on a baking stone as mentioned above.

The risk of a melted tub is there for sure. Keep an eye on it and test an empty tub first. The reward is also there: easy pasteurization + keep it closed until the exact moment of inoculation.

If risks are understood each one can make their own adult decision to look into this if they want. It works for me and I will never work with steamy scalding large pots and hot heavy wet substrate material. That is just my personal approach, to each their own.