Culturing mycelium to make Kinshi requires proper sterilization to avoid contamination. There are two main sterilization methods used: high-temperature sterilization and low-temperature sterilization. In this guide, I’ll walk you through the high-temp method, which I personally use. I haven’t experimented with low-temp yet, so I can’t speak to its reliability.
🔎 What You’ll Need:
▪ Pressure cooker (capable of 15 psi / 250°F)
▪ Autoclave tape (to verify sterilization)
▪ Mycelium in syringe form
▪ Oak pellets (base material)
▪ Wheat bran (nutrient supplement)
▪ Ethanol (for disinfection)
▪ Mushroom filter (for air exchange)
▪ Aluminum foil
📌 Containers that can handle high heat – Choose one of the following:
▪ Glass Jars
You can find these on Amazon. Be sure the lid is metal or designed for mushroom cultivation.
▪ Mushroom Bottles
These aren’t sold in the U.S. I personally import them from Korea
▪ Mushroom Grow Bags
These are available on Amazon
✅ Types of Mycelium Commonly Used
You can usually find mycelium syringes online.
The type you use depends on the beetle species:
▪ Oyster Mushroom (Hiratake)
Good for: Dorcus, Prosopocoilus, Phalacrognathus etc..
▪ Maple Oyster Mushroom (Ohiratake)
Similar to Hiratake, good for the same species
▪ Turkey Tail (Kawaratake)
Used for: Mesotopus tarandus, Mesotopus regius, Allotopus rosenbergi
▪ Reishi Mushroom
Similar to Kawaratake, good for the same species
✅ Kinshi Culturing Steps.
1. Hydrate the pellets
Use about 1.5x the weight of the pellets in water.
The moisture is right when the substrate clumps together when squeezed,
But no water drips.
2. Mix in wheat bran.
Add wheat bran at about 5–10% of the total substrate weight. 
3. Fill the containers.
If using jars, drill small ventilation holes in the lid and cover them with mushroom filters.
If using mushroom bottles or grow bags, skip this step
They already come with filters. Slightly compress the substrate when filling to prevent large gaps. (which can cause excess condensation and contamination later)
4. Apply autoclave tape to each container.
5. Wrap lids with aluminum foil.
6. Add water to the pressure cooker.
Around 1.5 to 2 inches of water.
7. Place a steam rack in the cooker and stack the containers on top
🔴 Keep containers from touching the sides of the pot. Bags especially can melt if they contact hot metal.
8. Sterilize.
Run the pressure cooker at 15 psi:
▪ Glass jars: 90 minutes
▪ Mushroom bottles: 2 hours
▪ Grow bags: 3 hours
9. Let the pressure cooker cool naturally.
Let it sit for about half a day. The lid won’t open anyway until it’s cooled down enough.
10. Remove containers and check the Autoclave Tape.
After sterilization, take out your jars/bags and inspect the autoclave tape. It should now show a silver or black stripe, which confirms the proper sterilization process was completed.
11. Inoculate with mycelium.
Make sure the containers are completely cooled down before proceeding. Disinfect your hands, syringe, and container surfaces using ethanol to prevent contamination. For best results, especially if you're doing this regularly, I highly recommend using a Laminar Flow Hood for a clean and safe workspace.
12. Let the mycelium grow. (incubation stage)
Store the inoculated containers in a dark place with stable temperatures.
📌 Ideal temp range: 65–75°F (18–24°C).
📌 Incubation time will vary depending on container size and how much culture you injected, but as a general rule, expect at least 1 month for full colonization.
