Frequently Asked Questions - Production

“Spawn” or “mushroom spawn” (sometimes wrongly called “mushroom seed”) is any material that has been inoculated with mycelium and used as a carrier to transfer the mycelium to a growing substrate.

With spawn, growers are assured of a pure, disease free culture that can be easily distributed throughout a growing substrate. Spawn comes in many shapes and forms: solid on grains, solid on sawdust, liquid on extract medium, liquefied on powder medium, etc. Mycelia sells spawn of a large number of species, on many recipes and of more than 150 strains to over 100 countries. Needless to say this variation is our specialty and our main sales product.

Mother spawn is the name we give our 2nd and 3rd generation of inoculum = before the 4th generation spawn. It can be produced on many types of carriers: grains, sawdust, slurry, liquid or any carrier which can grow fungi.

Notes:

• “Mother spawn” is not an internationally accepted term for this stage of multiplication, the term was invented at Mycelia 40 years ago. But there is no internationally accepted name. Different institutions and companies give it different names: inoculum, inoc, spawn master, master, pre-spawn, etc. We are eagerly awaiting the day that the industrial and scientific community will agree on a common name for this production step.
• There are not always 3 generations of multiplication before “spawn” is made. In the case of liquid fermentations for example, 2 generations are sufficient.

A petridish is a shallow transparent lidded dish that is mainly used in laboratories to grow bacteria, fungi and other micro-organisms on a culture medium. When the culture media on the bottom is based on a solidified agar solution, it is called an agar petridish or agar plate. 

There are hundreds of recipes, depending on the micro-organism(s) you want to study.

Two interesting all-round media for fungal growth are MEA (Malt Extract Agar) and PDA (Potato Dextrose Agar).

At Mycelia, all our cultures are grown on an MEA medium, with the exception of some species that have very specific requirements.

For the production of agar petridishes for quality control it is advisable to add extra glucose (20% of the total dry matter) to the MEA medium, in order to stimulate bacterial development and hence make infections visible. When sugar is added, the code changes to MEA+. In spawn laboratories, MEA+ agar plates are mainly used in quality controls to assess the growth of mycelium or reveal the presence of contaminations (moulds and bacteria). They can be bought on our Mycelia website in addition to mycelium products, on the cart page as you make an order.

Mother cultures and mother spawn are more expensive because they are evaluated through an extensive quality assurance system (microbiological and/or mushroom growing tests) before being released and introduced into a spawn production process.

These quality assurance tests are the guarantee that the quality of the mother spawn (axenic and vigourus mycelium) and the spawn performance is according to industrial standards.

Both are excellent.

But if you have a well organized lab with correctly functioning laminar airflow, agar petridishes plates have the advantage of a larger agar surface. Simply put, they are more practical.

But keep in mind that test tubes are better and safer than petridishes for long term storage: the stopper prevents the medium of drying out.

This question cannot be answered because it depends on many different factors:

• Mushroom species
• Growing conditions
• Substrate used
• Market requirements
• And many more…

If you want to produce spawn, you will need a spawn lab, or at least a small version of a spawn lab.

You will have to deal with either mother cultures and mother spawn, which you can order from a company like Mycelia.

The production of spawn must be carried out in the most hygienic conditions, with the appropriate installations and by appropriately trained personnel.

Spawn production is a technologically very advanced type of indoor agriculture, which is why it is usually referred to as biotechnology.

Spawn production is not like growing substrates or mushrooms.

In short: if you wish to produce spawn on a regular basis and for professional purposes, you will need the essential expertise. We teach this expertise in our group trainings and individual trainings in cleanroom technology and we can also assist in the design and organisation of professional spawn laboratories.

We can teach you the basics, but we cannot take you all the way. It takes many years to reach a high level in spawn production. For more details on our group training on spawn production, click here.

Yes, you can easily order them by going to our website and selecting your strain(s) in our webshop.

Then select the option “Mother spawn – liquid” in the dropdown menu.

We can also produce larger batches of 250 litres in our mobile fermentors. Contact our R&D team if you would like a quote.

Yes it can.

But not always. There are certain combinations of species and recipe which can be transported easily such as Agaricus bisporus (White Button) on grains, or Lentinula edodes (Shiitake) on sawdust, etc.

And of course you must have taken sufficient precautionary measures regarding cooling and hygiene.

But spawn is a living product and must be transported cool and quickly. The transport costs are elevated and the danger of reduced quality – due to overheating and others – at arrival is not imaginary.

More in-depth information can be found in some transport questions in our FAQ “About my order”.

Spawn is a living product! Its shelf life depends on:

• the strain
• the storage temperature
• the way it is stored.
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Strains with slow-growing mycelium have the longest shelf life. 

In chronological order of appearance, the signs of the ageing process of spawn are:

1. The mycelium / spawn becomes more compact
2. Observation / formation of skins, crusts and lumps
3. Production of colored liquid with or without unpleasant odor
4. Autolysis (self-destruction) of the mycelium and disintegration / degradation / damaging of the spawn
5.  

In the signs of the ageing process (1) and (2) the mycelium is perfectly useable, although it is less crumbly than totally fresh spawn. Since the autolysis of the cells begins at the end of stage (3), it is recommended to use the mycelium before that time. In stage (4) the mycelium is dying and should be discarded.

We do not indicate the shelf life on our spawn bags. Some producers do, but we consider it too difficult to give a guarantee.

The litre is the unit of measurement used in the spawn industry to make different types of spawn comparable. 

Mushroom spawn is a generic term for any material that has been inoculated with mycelium and which is used for further multiplication. The litre is a unit of measurement that represents a portion of space, not a weight. Depending on the nature of the materials you want to compare, they will be more or less heavy for the same volume.

These differences highlight the density of the materials, i.e. the mass that they occupy for a unit of volume. The density of these materials fluctuates:

1. due to the nature of the material itself (rye, millet, sawdust, liquid, etc… )
2. due to the humidity of the material obtained during the spawn production process.
3.  

We strongly advise against it. 

Agreed, it would save you a small amount of money. But our recommendation would be to use mother spawn to produce your spawn.

Why? In spawn production, it is essential to avoid too many multiplication steps (mycelium transfers) in order to avoid risk of contaminations and strain degeneration. Mother spawn follows strict rules of quality control before being released. It is the safer way to start a spawn production process and the extra cost usually does not outweigh the increased risk. 

You can easily order mother spawn in bags by going to our website and selecting your strain(s) in our webshop.

Important: If you choose to multiply our spawn into a next generation of spawn, we do not give you any guarantee as you are not using our products for their proper purpose.

Yes, it is possible but you will have to send us a request, so we can send you a quote.

That hinges entirely on your own preferences and work method.

There are a number of qualities that a good spawn bag needs to have:

1. Breathability / filtration: the bag needs to breathe without letting contaminants in, without drying out the substrate
2. Resistant: the bag needs to be sufficiently strong to survive manhandling
3. Heat and cold resistance: the bag needs to be sterilisable to 121°C (249,8°F) and coolable to 0°C (32°F)
4. Size: there needs to be enough space inside, without it being too large
5. Price: as most spawn bags are single-use, the price should be as low as possible
6. Ecology: the bag should produce as little waste as possible.
7.  

NOTE: There are many types of receptacles on the market, from bottles to containers, vessels and bags, but most professional spawn producers use breathing bags. 

Having problems in selecting your ideal breathing mycelium bags? Then use Sac O2’s “bag finder” to guide you in finding your perfect fit. Visit the website on https://saco2.com/catalogue and set your filter tags.

This is indeed essential if you wish to be a successful producer. You will have to take a great deal of precautionary measures, that are for the largest part equal to the GMP (Good Manufacturing Practices) of any cleanroom environment. Some measures however are very specific to our needs, such as the sterilisation of filtered bags.We distinguish 2 main topics:

1. Removing contaminants
2. Preventing contaminants from entering the lab
3.  

Let us explain them briefly:

Removing contaminants

• Sterilise all equipments and products in an autoclave. All materials that cannot be sterilised should be cleaned thoroughly as described in the FAQ below “What do you consider the correct procedure for cleaning?”
• Clean the cleanroom daily and more extensively weekly and even more extensively every so often. Follow the procedure as described below in the FAQ below “What do you consider the correct procedure for cleaning?”
• If and where necessary, use CIP (Cleaning In Place) techniques or disinfection methods such as UV light.
• Finally, make sure that any contaminated product is immediately taken out of the laboratory and destroyed to avoid spreading spores of mould throughout the laboratory.
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Preventing contaminants from entering the lab

• Use the correct dressing protocol for the workers
• Install a strict protocol for the product flow and for the movements of the workers
• Using a top quality bag for your products
• Using top quality equipment with stainless steel surfaces, good quality sealing machines, etc
• Filter incoming air through HEPA filters. Apply filtered overpressured air to your rooms, especially to your cooling rooms, inoculation rooms and the complete mother spawn department. Ideally, all stages of incubation receive overpressurized pure air too.
• Filter the air around any extra sensitive manipulations with a laminar flow cabinet. Examples are the workbench where you inoculate manually, the entry and sampling ports of liquid containers, the place where bags are filled or redistributed, etc. The air from these workbenches is filtered to zero contamination and is then diffused in a laminar flow towards the user. It creates an extra safe working space in the cleanroom.
• Check the workings of all Hepa filters at least once a year.
•  

If you need a profound understanding, follow a spawn course.

Cleaning is indeed of the highest importance.

You must be meticulous, even to the point of becoming obsessive, or you will fail.

Follow these basic rules at the end of each working day and extend where needed:

• First have a superficial cleaning to remove most of the organic matter that facilitates the multiplication of micro-organisms and to destroy some of the biofilm. It is in and under this biofilm that the multiplication of contaminants takes place, which will not react to disinfection products in the next step. Destroying this biofilm is the most important phase of the cleaning and disinfection process in a laboratory. It is really important to have appropriate and good tools to achieve this properly.
• Then disinfect all surfaces and materials of your lab. This phase should also remove all remnants of the biofilm, so that the disinfectant can do its work.
  
• Proceed to the rinsing of surfaces and equipment with (chlorinated) water or equivalent. This rinse will remove remaining particles, remove detergent residues (and sanitise surfaces through the chlorine action)
• Then proceed to the disinfection of all other surfaces by either 1) wiping surfaces and equipment with a disinfection solution or 2) by spraying disinfectant on surfaces and equipment or 3) by soaking equipment in a disinfectant or 4) by fogging the room.

If you need a profound understanding, follow a spawn course.