The linked fates of fungiculture and waste recycling

Growing mushrooms

Posted on May 21, 2024
Mycology is an activity that attracts many enthusiasts. Devotees will tell you emphatically that mushrooms are truly fantastic! Whereas edible mushrooms used to be associated with a relatively marginal fringe of society, consumers are now more educated about why they need to add them to their diet. This growing public interest has resulted in a booming market. Mushroom farms are multiplying, and production techniques are changing just as rapidly. It’s an effervescent world!
Catherine Dallaire, Agronome

Substrates for growing mushrooms

The variety of substrates that can be used for mushroom growing is astonishing. Among the more conventional ones (for example composts, sawdust, straw or grains) are materials that are useful for other purposes and therefore, in general, relatively expensive.

Recent studies, however, have explored the effectiveness of lesser-known substrates, such as bean pods or various residues from the hemp industry, with surprising results.

Recycling materials in mushroom production facilities

There is therefore an opportunity to recycle materials from other sectors, such as the forestry, food, agricultural and sometimes even industrial industries. Of course, these substrates have to meet certain health and quality criteria, as they are used to produce food for human consumption.

It’s also important to bear in mind that mushrooms fall into different categories, requiring substrates with different criteria. It is therefore important to choose the right substrates to ensure the proper development of mycelium and mushrooms. In recent years, some fungiculturists have successfully used spent grain from the brewing industry in their substrate mixes. Whether we’re thinking of fibres, grain or nut hulls, or even soy hulls from by-products such as tofu, it’s easy to imagine that many companies could become an almost inexhaustible source of growing substrate for mushroom farms.

However, the preferred option is to use residues that are locally accessible and useless for other purposes. In this case, we’re talking about recycling materials that would otherwise be thrown away, including the nutrients they contain. Economically, this means substantial gains for all parties involved. Doesn’t waste management represent a huge cost for companies?

Let’s talk, on a small scale, about the many pounds of waste from restaurant kitchens or, on a larger scale, the tons of residues from food factories.

The role of mushroom farms in circular economy

The concept of the circular economy aims to rethink the economy by optimizing the use of the resources that already exist in our society, notably through their repair, recycling and repurposing.

What if we decided to think more about the potential of mushroom farms as an important rung in the circular economy loop? In other words, we decide to set up mushroom farms in communities where there is already a vibrant agri-food industry, so that they are ideally placed to easily recover residues that are destined for landfill. This is a circular economy strategy known as industrial ecology. Production techniques could then be adapted to these specific substrates from the outset.

Our knowledge of all the potential uses for mushrooms is still very limited. So there lies a huge potential for Quebec and for innovative minds!

Catherine Dallaire, Agronome