When creating liquid cultures from spores, it is crucial that all jars be sterilized before adding mycelium. Use an alcohol-sterilized syringe or needle to transfer mycelium from one container to the next.
Once the jars have cooled, add a magnetic stir bar and regularly shake your culture to introduce oxygen and prevent mycelium clumping, encouraging growth.
Liquid culture production is key to successful mushroom growing at home, whether experienced or beginner alike. A liquid culture is a living mixture of nutrients and water inoculated with mushroom spores or mycelium that acts as an instant starting point for colonization.
Producing liquid culture requires some basic tools. For starters, you will require a canning jar, an airport lid, aluminum foil, pressure cooker, liquid culture syringe, isopropyl alcohol and magnetic stir plate or stick.
Liquid cultures typically use a mix of sugar and water. Honey water may work best, while others find light malt extract (Karo) with honey as the optimal combination. Experimenting with different sugars will help find one that fits with your growing environment and preferences best, creating an nutrient-rich solution with mycelial blobs floating across its surface.
Liquid cultures (LCs) are increasingly popular with growers due to their higher success rate over spores alone and lower maintenance requirements. Before using an LC, make sure all tools and surfaces are sterilized using isopropyl alcohol before placing it under an effective laminar flow hood for best results.
Liquid cultures typically use an LME recipe and may be added directly to grain substrate or wood chips for cultivation. This solution has approximately 4 percent sugar content to aid mycelium growth; some growers add additional ingredients such as essential oils to speed up mycelial development and colonize substrate more rapidly.
To use the LC, first sterilize your jar and injection port-equipped grain spawn bag by holding them under an alcohol flame until their injection port glows red (or follow the instructions provided with your kit). A syringe and scalpel may also be necessary for transferring agar onto agar plates.
Add an airport lid (or modified mason jar) fitted with a self-healing injection port and air exchange filter, either purchased online or modified yourself using mason jars as cheaper alternatives. Prior to sterilization, be sure to cover both components with foil so they do not become wet during the sterilization process.
Liquid culture can be used both independently or with colonies grown on grain substrate, using aseptic techniques. When inoculated, be sure to monitor regularly for signs of contamination.
Many growers advise stirring or shaking a liquid culture on a daily basis to break up any solid mycelium cluts that may form and ensure it is distributed evenly, as this will also reduce incubation times and improve aeration. To increase vigorous agitation for those cultures that require this level of vigorous stimulation, an Erlenmeyer flask with at least 20 times the volume of culture should be used so adequate air exchange can occur during cultivation.
Create a mushroom liquid culture is an indispensable step for any grower, regardless of experience level or scale, but requires special equipment like a pressure cooker and clean environment for inoculation.
Once your mycelium has successfully expanded into an nutrient-rich solution, it’s ready for long-term storage in the form of a jar kept in the fridge; typically this should remain viable for 6-12 months.
Many growers recommend shaking or swirling jars daily, to evenly disperse mycelium throughout the jars and prevent mycelial clumps from forming. A magnetic stir bar or marble stone (in LC) are great tools for this task as they help break up mycelial clumps more efficiently. Isopropyl alcohol should also be used before and after handling mushroom liquid cultures to prevent contamination; mold growth or cloudy liquid may be indicators that something is amiss so keep an eye out for these signs!