Pre-sterilized Grain Bag with Injectable Port


Small 3.0 mil thick polypropylene plastic spawn bag with a 0.5 µm filter patch at the top and a built-in foam self-healing injection port at the bottom that is filled with 1kg hydrated white proso millet that has been sterilized at 15 PSI for 2 hours.

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This ‘small’ sized, injectable mushroom filter patch spawn bag measures 4″ x 3″ x 18″ with gusseted sides and a 0.5 micron filter. This bag is composed of autoclavable 3.0 mil thick polypropylene plastic. The 0.5 µm filter is ideal for both spawn and substrate production. The filter is located at the top of the bag, which allows for more grain or substrate to be loaded into the bag when compared to other bags on the market. The microporous filter patch allows for filtered gaseous air exchange while keeping contaminants out. The built-in foam self-healing injection port is located towards the bottom of the bag which is the ideal location for inoculating with an edible variety spore or liquid culture syringe.

The product will come with 1kg of hydrated white proso millet grain that has been sterilized at 15 PSI for 2 hours. It has been triple sealed at the top 1.5″ using an impulse sealer after sterilization in front of a laminar flowhood to keep out contaminants. This is ready to be inoculated with your favorite edible variety such as Oyster, Lion’s Mane, Chestnut, Shiitake, Pioppini, and Reishi.

We ship this in a USPS Priority Medium Flat Rate box so you can expect your order 1-3 days after we ship your order.

Easy To Use For Grain Spawn!

Why millet?

Millet has a much lower endospore load than rye and wheat, making it less prone to contamination. And its small size means your spawn will have many more inoculation points for the same volume of grain. By using millet, the mycelium will spread more evenly and abundantly through the substrate. And, as a high-nutrient medium, it also encourages rapid mycelial expansion.

Grain bags should be stored at room temperature out of direct sunlight. No refrigeration is necessary. They can also be stored for several months before use.

Additional information

Weight1 kg