How to make liquid culture? - Instruction Guide

What is a Liquid Culture?

• A liquid culture consists of a sterilized nutritious solution. This is usually a mixture of water and various kinds of sugars.
• The mixture has the ability to develop mycelium growth, when inoculated with spores.

Advantages:

• Faster result: The cultivator no longer has to wait for spores to germinate, thus reducing incubation times by at least a week.
• Limitless mycelium growth: 1cc spore solution can be used to create a limitless amount of liquid culture. Because once mycelium starts developing, it keeps developing.

Be sure to read these step-by-step instructions to guide you through the process.

This article will focus more on how to make Liquid Culture. Catch up with this informative article on what Liquid Culture exactly is.

How to make liquid culture? - Honey/Water Instructions

Liquid cultures are normally at a 4% dilute solution of various sugars and other nutrient sources in water. This would be 4 grams of sugars per 96 ml/cc water. (Water weighs 1 gram per ml/cc.)

The most used nutrient sources are:

• Honey (Non-organic has been known to work, but organic honey is highly recommended.)
• Karo
• Corn sugar
• Light malt extract
• Dextrose (glucose)

Household sugar (sucrose) shouldn't be used!

To make this instruction guide easy and accessible for everyone, we would like to focus on the nutrient source that is most common: honey!

 How much honey?

• 4 cc/ml is the exact 4% ratio wanted.
• Another way to measure 4cc/ml of honey is 1 teaspoon.

1 teaspoon of organic yellow honey to 100ml water is fairly close to the right ratio!

If your solution is a little off (3%-5%), don't worry. 

Just remember: it is better to be too weak than too strong, because too much sugar (around 10%) is toxic for the mycelium, and will not let anything grow in it.

Mixing & cooking

Once you have picked your method, its time to do some mixing.

Optionally, water can be hot or warm before adding sugars to allow for quicker dissolving.

Wrap the top of the jar with aluminum foil and place the jar in the pressure cooker. Slowly bring it up to 15 psi. for 15-20 min. No longer! 

With honey, is important to know that if you pressure cook too long, your solution may turn yellow. This is called caramelization, the over-baking of the sugars, which may result in little or no growth.

Allow the pressure cooker to cool off before removing.

How to make a vacu-tainer?

• Bore a small hole big enough for a syringe needle in the lid/screw cap of your jar. (Half pints work best for this).
• Put a blob of silicone sealant on it (preferable transparent) on both sides.
• Swirl it around to make sure it is a centimeter thick around the hole on each side.

This is a self healing inoculation point so you can add spores and suck up inoculant without having to open the jar after sterilization. Always sterilize the needle with a flame and wipe your silicone injection spot and your needle  with alcohol before inoculation.

Measurement notes

• 1 ml water weighs 1 gram.
• 1 tablespoon dextrose weighs ~10 grams. (may vary slightly)
• 1 tablespoon light malt extract weighs ~10 grams. (may vary slightly)
• 10 ml honey weighs 14 grams.
• 1 tsp (5 ml) honey = 7 g
• 1 tbsp (15 ml) honey = 21 g