Closed Loop Mushroom Production on 100% Waste Substrate

Project Overview

Project Type: Farmer/Rancher
Funds awarded in 2013: $7,623.00
Projected End Date: 12/31/2013
Region: Southern
State: North Carolina
Principal Investigator:
joseph allawos
Asheville Fungi

Information Products

Waste Stream To Protein (Conference/Presentation Material)


  • Miscellaneous: mushrooms


  • Crop Production: municipal wastes
  • Education and Training: demonstration, farmer to farmer, on-farm/ranch research, youth education
  • Energy: energy conservation/efficiency
  • Farm Business Management: whole farm planning, value added
  • Production Systems: organic agriculture
  • Soil Management: organic matter
  • Sustainable Communities: community services, sustainability measures


    Study Overview:

    A study was conducted to determine the feasiblility of using 100 percent waste stream substrates for commercial edible mushroom production.  The target species was Pleurotus ostreatus, the common tree oyster.  Biological efficiency of four different waste substrate mixtures was compared to that of the commercial standard substrate mixture consisting, by dry weight, of 80 percent oak fuel pellets, 18 percent wheat bran and 2 percent gypsum.  The four waste substrates were spent coffee grounds, cacao shells, soy "dust and husks", and malthouse "fines and beards".  The four formulations were created by using these substrates in place of the bran as the enriching agent and combining them with  mixed species sawdust from a local sawmill.  The sawdust replaced the fuel pellets as the carbon and lignin source in the study.  The substrates were innoculated and fruited out and the spent substrate was composted.  The compost was sampled and tested for nutrient values and cation exchange capacity.  The powerpoint presentation attached below describes in great detail the entire study and includes graphic information.  We would advise the reviewers to use the power point to get greater detail than has been provided in the text below.



    • Thousands of pounds of waste stream products are discarded into landfills every day in every city in the world.
    • Many of these products may be suitable as substrates for growing edible and medicinal mushrooms.
    • This study will determine the feasibility of using these substrates in commercial mushroom production.

    Project objectives:


    • To develop substrate formulations that utilize readily available waste stream products for growing edible mushrooms.
    • To compare the yields of waste stream substrates to that of the “industry standard” commercial substrate formulation
    • To compost spent mushroom bags for use  as a nutrient rich fertilizer, thus closing the               loop.

    Any opinions, findings, conclusions, or recommendations expressed in this publication are those of the author(s) and do not necessarily reflect the view of the U.S. Department of Agriculture or SARE.