One of the most important aspects of growing mushrooms commercially or at home is genetic preservation. Most literature will tell you to keep your spores in a cool dark place and they will be fine for years, although this might work for your at home projects it’s not the end all solution. The best method for storing mushroom spores is with a digitally controlled wine fridge. Most standard refrigerators will vary in temperature depending on the location in the space, generally the lowest area of your fridge will maintain the lowest temperature. Regulated temperature control fridges are key in spore storage.
A liquid culture syringe can last for multiple years in the refrigerator if the genetics are stored in the proper medium. Low nutrient recipes will generally survive the longest, by adding a minimal amount of food source will slow down the growth of the culture (1 gram light malt extract per liter).
Approximately 39-41 degrees Fahrenheit is what I found to be the most effective range for long term storage ( 4-5 plus years) . This goes for both spores and liquid culture. Spore swabs, culture syringes should be kept in the refrigerator until 24 hours prior to use. Once the material reaches room temperature you can inoculate your grain spawn or all in one grow kit. The main reason you want to maintain your genetics with a digital wine fridge is because you will never have to worry about unstable conditions, if a culture or cell gets freezer burnt it will cause the cells to “lyse” or break and degrade your genetics or worse make them inactive and unable to colonize completely.
It is important to note even when storing mushroom spore swabs refrigeration is the best practice for genetic maintenance. Some the best mushroom growers in the world use spore swabs to store isolated variety’s. The best way to prove a mushroom sample is an aggressive isolation is by running the spore swab on an agar plate and adding the first or second transfer to a one pound grain bag to verify a proper yield. Spore swabs are hardy and are not temperamental when environmental conditions change during international shipping or being mailed across the country during a heat wave for example.
The best technique to date for storing isolated mushroom cultures in agar is with conical 15 ml test tubes. By filling the tubes half way with sterile distilled water you can cut wedges of colonized agar plates into the water tubes. These should be left at room temp over night so the water can properly saturate the agar wedges and then placed in the fridge for up to 4-5 years. Once you want to re start your genetics you simple scoop one wedge out of the water tube and place on a new agar plate.
Step 1 : take a mason jar and fill with distilled water. Step 2: use a syringe to withdraw the water and load each individual tube with 10 ml of water Step 3: add 5-10 wedges of colonized agar into the test tubes. And seal with parafilm or grafting tape. Step 4: Label and leave overnight until storing in the fridge