Let's talk about how to store liquid culture syringes. Liquid cultures are one of, if not the most popular starting place for many mushroom enthusiasts. It is quite easy to buy high quality mushroom liquid cultures online and they grow quickly.
But did you know that a liquid culture contains living mycelium? That’s right. A liquid culture is a syringe filled with a nutrient broth in which living mycelium is suspended. That is why they grow so quickly - they are already alive!
This is also the reason that proper storage methods are essential. The living mycelium inside of a liquid culture will be drastically affected by how you store it. Poor storage methods can lead to decreased viability, contamination, and lowered genetic-stabibility.
Good storage methods can save you time and money in the long term. You don’t want to start growing some mushrooms from some old liquid cultures only to find they are contaminated after weeks of waiting for your grains to colonize. What a waste!
Liquid cultures can last 6-12+ months under ideal storage conditions. It is really not that hard either. In this article we are going to teach you everything you need to know about storing liquid cultures so they remain contaminate-free for up to a year or more.
You want to store your liquid cultures in refrigerator temperatures. Between 35-46℉ is the best for storing liquid cultures. At these lower temperatures, the living mycelium inside the liquid culture slows its metabolism. This prevents overgrowth and the depletion of essential nutrients. Not only that, but the lower temperatures also inhibit bacteria growth so your LC can remain contaminant-free!
Be careful not to make the temperature too low or else you may run into some other problems. Freezing temperatures can kill or weaken the liquid culture.
If you are storing your liquid cultures at room-temperature, it is highly suggested that they be used within 1-2 weeks before you run a high risk of contamination.
Determining whether you want to store your liquid cultures in syringes or jars is really based on how long you need to store the liquid cultures for. Syringes are best for short term storage and frequent use. This means less than 12 months, but more ideally less than 6 months. Syringes are beneficial because they are easy to label and dose.
If you plan to store your liquid culture for more than 12 months or just longer periods in general (say, over 6 months), then jars are probably ideal for you. Jars are less prone to contamination than syringes are. They are a great way to build up a culture library.
Properly stored liquid cultures are generally stable for about 6-12 months. You can get more time from certain strains, but it is usually best to play it safe.
Regardless of how long you store the cultures, you should test them on agar every few months just to confirm they are still viable and contaminate-free. Simply plunge a few mL of culture onto an agar plate and see how it develops. You will be able to easily see any contamination.
If your culture turns cloudy, yellow, smells bad/rotten, or develops slimy sediment, then chances are it has gone bad. There are ways to save a cloudy culture (check our blog for more info), but the culture may be a lost cause if any of these signs persist.
Contamination most often occurs before your store the liquid cultures. Usually during inoculation or handling. Here are a few best practice tips you can follow to try to avoid any pre-storage contamination:
An organized culture library makes your life easier - trust us…
You should label every liquid culture with strain name, date you made it, generation number (if you cultured multiple generations), and notes about the culture (like if it grows quickly or fruits a lot). Labeling your cultures is very important so you don’t make any easily avoidable mistakes such as mixing strains or losing track of cultures. You can even digitize your library for even more accessibility!
