Lab Techniques

Boiling water (100°C) kills most bacteria but not heat-resistant spores. Only pressure-cooking (15 PSI, 121°C, 90 minutes for grain bags) reliably sterilizes mushroom substrate.

Cutting corners here is the single most common cause of failure. If a recipe says 90 minutes at 15 PSI, do 90 minutes.

Agar plates let you isolate a single clean strain from contamination, multiply spawn from one cell, and store cultures long-term.

Start with MEA (malt extract agar) — most species love it. Pour plates in a still air box, inoculate from a spore syringe or tissue clone, watch for growth in 5–10 days.

Liquid culture (LC) is sterile sugar water inoculated with mycelium. Once colonized, one jar can inoculate dozens of bags via syringe.

Cheaper, faster, and cleaner than grain-to-grain transfers — but requires sterile technique. A single bacterial contaminant ruins the whole jar.

Cut a fresh, healthy mushroom in half with a sterile scalpel. Scoop a tiny piece of internal flesh (never the surface) and place on agar.

You're copying a single genome — useful for cloning a strain that produced exceptional fruits. Most commercial strains exist because someone cloned a good wild specimen decades ago.

Agar slants in the fridge keep cultures alive for 6–12 months. Cryogenic storage (in glycerol at -80°C) holds them for years.

Always keep a backup slant of any strain you care about. Cultures die, contamination happens, fridges fail. Redundancy is cheap insurance.