The substrate would be the nutrient-rich product on which your mycelium will expand. Typical substrates include things like brown rice flour mixed with vermiculite and drinking water (typically referred to as BRF cakes) or full grains like rye or millet. The substrate needs to be thoroughly pasteurized to circumvent contamination. https://magicmushrooms55429.blog2freedom.com/38695197/a-review-of-brazilian-cubensis