This basic liquid culture recipe works well with most strains. It combines one gram of Light Malt Extract in 600 milliliters of water to provide a clear environment in which mycelium thrives.
As part of your mycelium distribution strategy, it’s advisable to shake or stir your jars periodically. Doing this helps evenly disperse mycelium growth throughout your grow medium.
Ingredients
Liquid culture recipes tend to be straightforward, using ingredients readily available in most home kitchens. These ingredients provide early-stage mycelium with nutrients it needs for rapid colony formation and robust growth.
For optimal results, most recipes begin by creating a nutrient broth from water and either light malt extract or honey at a ratio of 4:1, depending on the strain being grown.
Regular stirring agitates the mixture and helps spread mycelium throughout. Furthermore, regular stirring helps avoid any clumps forming within the jar.
When starting a liquid culture, make sure all jars or media bottles as well as tools are thoroughly sterilized with 70% isopropyl alcohol before adding your spores or mycelium. Sterilized jars provide ideal storage of mycelium produced, and only add it into sterile medium. Each jar acts like its own mini incubator; improper sterilization could result in contamination. For optimal results use magnetic stir bars or small glass marbles in each jar to help with agitation for best results results.
Preparation
Starter kit items needed for liquid culture are: airport (grain spawn) jar with syringe port in lid and sterilized needle. An airport jar is preferable as it allows seal and has the syringe port located safely out of reach from contaminants entering through its lid syringe port.
Once the jar has been assembled, water and nutrients such as honey should be added for feeding the plants. Light malt extract, corn syrup or dextrose will all work just as effectively.
Agitate the mixture to break up any clumps of mycelium and evenly disperse nutrients, either manually swirling, shaking, or using a magnetic stir plate for maximum effectiveness. Good agitation also serves to prevent contamination; if cloudiness, discoloration or smell appear within 24 hours it is most likely contaminated and should be discarded immediately.
Substrate
Liquid cultures differ from spores by being composed of live mycelium that can colonize substrate immediately, making them perfect for beginner mushroom cultivators looking to accelerate the colonization process. Liquid cultures tend to grow quickly once transferred onto grain substrate, making them suitable for speedier colonization processes and faster cultivation times.
As soon as mycelium begins to form in liquid, regular agitation becomes important in order to break up and disperse it evenly. You can either shake the jar, or use a magnetic stir bar (ideally set it at low speed for optimal results). To achieve this effect, use either method – shaking will do fine but setting up your stir bar on low speed can avoid excessive turbulence.
Test liquid cultures regularly for signs of contamination, looking out for anything suspicious such as unnatural colors or smells, to detect disease-spreading pathogens. Once healthy liquid cultures have been properly maintained they should last months (if not years) until consumed completely.
Incubation
Liquid culture can speed up colonization and decrease incubation times. But to achieve maximum effectiveness, a clean work environment and technique must be employed in order to prevent contamination – it may be difficult to detect in a cloudy medium; any small breach in sterility could put your entire batch at risk.
Make sure the jars and lids you are using for liquid culture are cleaned and sterilized; Mason jars or similar glass bottles typically work well. Also ensure that their lids have features tailored for liquid culture such as self-healing injection ports (for injection and withdrawal of culture) and air exchange filters; you can either purchase such features online or adapt regular mason jars with minor modifications to accommodate liquid culture needs.
Use a sterilized needle or spore syringe to inject mycelium solution into jars. Gently mix each jar to distribute mycelium evenly throughout its contents and place incubation in a warm dark environment (18-20c/64-68f). Check on jars daily for signs of contamination or temperature variations – they should also be gently shaken each day in order to promote mycelial growth.