Mushroom Cultivation: Upcycling – Community Wastes And Mushroom Cultivation

Eco-friendly organic mushroom cultivation

Community wastes and mushroom cultivation

TMI is committed to promoting the cultivation of organic and environmentally friendly mushrooms. Over the years, we have used the organic waste from the community (such as kitchen waste, bean dregs, and coffee grounds etc.) for growing mushrooms and used recycled glass bottles as the cultural container in order to substitute the common used plastic cultural container in edible mushroom industry.

In order to match the local climate and environment, we selected Pleurotus ostreatus and Ganoderma lucidum as key cultivated strains. We use natural materials for all cultural media preparation and all materials pass the strict pesticide and heavy metal inspection. We have obtained the certification from “Hong Kong Organic Resource Center” for many years.

Procedure of mushroom cultivation

It can be divided into “3 stages” or “5 steps”.

3 stages:
  1. Cultural medium preparation and inoculation;
  2. Growth of mycelium;
  3. Bud induction and growth of fruit body.

5 Steps:
  1. Preparation of cultural medium;
  2. Sterilization of cultural medium;
  3. Inoculation;
  4. Bud induction;
  5. Management of fruit body.


(1) Preparation of cultural medium:

Materials:
Wood dusts, bean dregs, coffee grounds, sucrose, water and lime were mixed in appropriate ratio;

Sterilization:
The mixed cultural medium is aliquoted into glass bottles and autoclaved at 121℃ for 1 hour;

(2) Growth of mycelium

Primary culture is inoculated into the sterile bottles in a laminar airflow bench. The inoculums are then incubated at room temperature in mycelium growing room.

(3) Bud induction and growth of fruit body

Bud induction:
When the bottles are full of mycelium, buds are induced by various physical methods according to different species.

Growth of fruit body:
Cultures with buds are then transferred to fruit body management shed to maintain >80% humidity and ventilation. Finally the fruit bodies are harvested according to their size.

Comparison of mass conventional cultivation and organic cultivation

Cultivation method
Eco-friendly organic method
Organic method
Mass conventional cultivation

Cultural materials
Recycled materials from local community
TMI: wood dusts, bean dregs, coffee grounds, kitten waste etc.
Organic source of sawdust, agricultural waste, such as: corn millet, lotus seed hulls, straw, animal manure, etc. (depending on mushroom species)
Sawdust, agricultural waste, such as: corn millet, lotus seed hulls, straw, animal manure, etc. (depending on mushroom species)
Additives: chemicals and hormone

Container
Recycled glass bottles
Plastic containers
Plastic containers

Strain
Species adapt to local climate
Customer dependent
Customer dependent

Incubation room
Simple shed with watering to maintain suitable humidity
Automatic environmental control: humidity, temperature, oxygen level etc.
Automatic environmental control: humidity, temperature, oxygen level etc.

Transportation
Local source
Global source
Global source

Waste after cultivation
Use as Fertilizer
Dispose of as waste
(usually with plastic bag)
Dispose of as waste
(usually with plastic bag)

Impact of conventional cultivated mushrooms on the environment

Do you know where your favorite mushroom comes from? With ever increasing demand from hungry consumer, traditional mushroom farms had shifted from log culture to (plastic) bag cultivation. What are these and, is bag cultivation more eco-friendly?

Traditionally log cultivation uses only logs from board leaf tree, where bag cultivation on the other hand uses a mixture of agriculture waste as substrates. Thus many people say bag cultivation is more eco-friendly because has lower demand in wood, thus effectively conserved forest. However, there’s question associate with bag cultivation as well. Firstly, carbon footprint for raw material such as woodshed, cottonseed hull and plastic bags would be higher if distance between site of production and farm located far apart. Secondly, as the name applies, bag cultivation generates huge amount of persistent hard to degrade plastic waste. All mushrooms species we consume were originated from nature at first, where each species has their optimum environment corresponding to local weather. Many consumers however, only consume food according to their preference, without questioning where and when that food ought to grow.

Such inconsiderate consumption pattern demands huge energy demand in every step of production. Using Enoki cultivation as example, mushroom farmer grows it in an entirely manmade condition. Switching on air-con to maintain temp at 4℃ along with artificial florescent and humidifier throughout entire cultivation phase. Do not forget most of our foods are imported from all around the world, including Taiwan, Japan, Korea and China significantly increasing carbon footprint during transportation.

You will be shocked to learn enormous energy input to grow food against natural climate. All of these problems initiate with your choice, are you willing to change your consumption practice for our Earth?

Safety of TMI’s mushrooms

Our mushrooms were tested by Eurofins for heavy metals and pesticides in 2019. All items are below the maximum permitted concentration in Hong Kong.

Species   P. ostreatus
410
P. ostreatus 03 P. geesteranus A. aegerita
Heavy metals Max. permitted concentration (mg/kg)* Measured concentration (mg/kg)
Lead (Pb) 6 <0.05 <0.05 <0.05 <0.005
Cadmium (Cd) 0.1 0.03 0.04 0.08 <0.1
Arsenic (As) 1.4 <0.1 <0.1 <0.1 <0.05
Mercury (Hg) 0.5 <0.005 <0.005 <0.005 <0.1
Chromium (Cr) 1 <0.05 <0.05 <0.05 <0.1
Tin (Sn) 230 <0.2 <0.2 <0.2 <0.01
Antimony (Sb) 1 <0.05 <0.05 <0.05 <0.1
Pesticides Not detected**

* Part V (Food and Drugs) of the Public Health and Municipal Services Ordinance (Cap. 132) (Highlights).

** Lists of pesticides SU311 and SU312 from Eurofins.