Fruiting Body vs Mycelium: Why It Matters (And Why Most Mushroom Coffee Gets This Wrong)
Written by the Myco+ team.
Pick up almost any mushroom coffee on a South African shelf and flip it over. Somewhere in the ingredients list, you'll usually find one word doing a lot of quiet work: mycelium.
It sounds scientific. It sounds potent. It is neither the problem nor, on its own, dishonest — but it's also not the mushroom most people think they're buying. And the difference between mycelium and fruiting body is the single biggest quality gap in the mushroom coffee category right now.
What's Actually in the Bag
A mushroom has two life stages that matter here:
Mycelium is the root-like network the fungus uses to grow — typically cultivated on a bed of grain (usually rice, oats, or rye) in a lab. When companies harvest "mycelium," they often don't separate it from that grain substrate. The result gets dried and ground into powder that's frequently 50–90% starch from the grain it grew on, not mushroom.
Fruiting body is the mushroom itself — the part you'd recognise if you saw it growing. It's what's harvested when you picture wild Reishi on a tree stump or Lion's Mane's white, shaggy cluster. This is where the compounds people actually take mushroom supplements for — beta-glucans, triterpenes, hericenones — are concentrated.
Mycelium-on-grain products aren't fake, exactly. But labelling a product "1500mg mushroom" when a large share of that weight is oat starch is, at best, misleading. At worst, it means you're paying mushroom prices for what's functionally a fibre supplement.
Why This Isn't Just a Technicality
The research behind functional mushrooms increasingly distinguishes between fruiting body and mycelium precisely because they differ in bioactive compound profile — researchers studying Lion's Mane and cognition, for instance, have specifically chosen fruiting body extracts for that reason.[1] When a product doesn't specify which part of the mushroom it uses, or lists "mycelium" without disclosing the grain content, there's a real gap between the dose on the label and the compound profile the underlying research is based on.
There's also a compound-specific issue. Take Lion's Mane: its cognitive-support compounds split into two families — hericenones, found richly in the fruiting body, and erinacines, more concentrated in mycelium.[2] Most consumer-facing studies on memory and focus have used fruiting body extracts standardised for hericenone content. A mycelium-only product isn't delivering the same compound profile the studies used — even if the label says "Lion's Mane."
How to Check This Yourself
Most brands won't say outright which form they use, but there are a few reliable tells:
Look for the words "mycelium on grain" or "mycelial biomass" in the ingredients — this is the clearest giveaway.
Check for a beta-glucan percentage. Fruiting body extracts standardised to a specific beta-glucan content (often 20–30%+) are a strong signal of quality; grain-heavy mycelium powders rarely disclose this because the number would be unflattering.
Look for a milligram figure per mushroom, not just a total blend weight. "500mg mushroom blend" could be almost anything. "1000mg Lion's Mane fruiting body" is a claim you can actually evaluate.
Be wary of "extract" with no ratio. A "10:1 extract" tells you concentration; an unqualified "extract" tells you nothing.
The Simple Question to Ask Any Mushroom Brand
Before you buy any functional mushroom product, ask two things:
1. Fruiting body or mycelium? If the label doesn't say, that's usually because it's mycelium.
2. How many milligrams, exactly? "Contains Lion's Mane" tells you nothing. "1000mg fruiting body Lion's Mane per serve" tells you everything.
Named ingredients, named amounts, fruiting body specified — that's a reasonable baseline for any functional mushroom product, not just ours. It's worth checking for on anything you buy, wherever you buy it.
This article is for general information and has not been evaluated by SAHPRA. It is not intended to diagnose, treat, cure or prevent any disease, and is not a substitute for professional medical advice.
References
1. Docherty, S. et al. "Acute effects of a standardised extract of Hericium erinaceus (Lion's Mane mushroom) on cognition and mood in healthy younger adults." Frontiers in Nutrition (2025). https://www.frontiersin.org/journals/nutrition/articles/10.3389/fnut.2025.1405796/full
2. Thongbai, B. et al. "Lion's Mane Mushroom (Hericium erinaceus): A Neuroprotective Fungus with Antioxidant, Anti-Inflammatory, and Antimicrobial Potential — A Narrative Review." PMC (2024). https://pmc.ncbi.nlm.nih.gov/articles/PMC12030463/