Grantee Research Project Results
Final Report: From Garbage to Gourmet: Sustainable Waste Prevention and Mushroom Cultivation from Used Coffee Grounds
EPA Grant Number: SU835510Title: From Garbage to Gourmet: Sustainable Waste Prevention and Mushroom Cultivation from Used Coffee Grounds
Investigators: Mladenov, Natalie , Slough, Anastasia , Chapman, Jacob , Hong, Joseph , Oldani, Kaley
Institution: Kansas State University
EPA Project Officer: Packard, Benjamin H
Phase: I
Project Period: August 15, 2013 through August 14, 2014
Project Amount: $9,391
RFA: P3 Awards: A National Student Design Competition for Sustainability Focusing on People, Prosperity and the Planet (2013) RFA Text | Recipients Lists
Research Category: Pollution Prevention/Sustainable Development , P3 Challenge Area - Chemical Safety , P3 Awards , Sustainable and Healthy Communities
Objective:
From Garbage to Gourmet is a pilot study that is focused on the reduction of waste to landfills by introducing a composting pilot study at Radina’s Coffeehouse & Roastery in the Leadership Studies Building on the Kansas State University campus in Manhattan, KS. Instead of landfilling the organic waste produced at Radina’s, both pre-consumer and post-consumer compost is collected and new receptacles for compost have been set up in the coffeehouse. One novel aspect of this pilot study includes cutting-edge research on different mushrooms species that can be cultivated from the spent coffee grounds. The project relates to the three aspects of sustainability as follows: 1) People gain knowledge about the benefits of composting, as well as how composting affects them directly by decreasing landfill waste and landfill pollution, which ultimately is beneficial to public health; 2) The project relates to prosperity through long term savings by reducing landfill trash and potential revenue generation in the form of useful products (edible mushrooms and compost) being produced from the diverted waste; and 3) The planet benefits in that waste sent to landfills is reduced, which reduces the production of methane and CO2, and instead produce a beneficial soil amendment as compost.
Our proposal features a pilot study of an economically- and culturally-feasible closed loop waste management system, the “From Garbage to Gourmet Project”. In this pilot study, spent coffee grounds that would otherwise be landfilled are being used to create local and high quality edible mushrooms before they are composted. The project introduces the option of composting food waste to students at a popular coffee house on the KSU campus and educates the community about the importance of sorting waste and disposing it properly. To promote successful performance of this first waste separation-with-composting station, employees and customers have been trained to sort their waste. Currently signs are displayed above each waste receptacle bin to demonstrate the differences between trash, compost, and recyclable materials. The project is ongoing and educational tri-folds and posters are being professionally designed to explain the importance of separating waste and highlight the profitability of material reuse and composting. One of the strengths of this proposal is that it is student led and builds on the diverse skills of this interdisciplinary group of KSU students.
Kansas State University recently transitioned to a single-stream recycling system in the spring of 2013, which has increased the diversion of waste materials to the landfill from 20% to 25% campus wide. Radina’s Coffeehouse & Roastery is currently diverting 15% of material from the landfill by recycling. The introduction of pre- and post-consumer composting has allowed for Radina’s Coffeehouse & Roastery to divert 30% additional material that would otherwise have been sent to the landfill. Unfortunately, contamination of compost is a frequent issue. Since the launch of the pilot study, the staff of the Leadership Studies Building has now made it a requirement that future contracts with food vendors at the Radina’s location will have to provide receptacles for compost.
To further benefit from diverting organic wastes from landfills, a portion of the compostable material, specifically the spent coffee grounds, is reallocated for the purpose of researching mushroom cultivation and producing edible gourmet mushrooms for the community. By doing so, the remaining nutrients in the waste can be efficiently extracted for human health, in the form of edible mushrooms before being recycled back into the soil. From earlier mushroom substrate trials nameko, pearl oyster, and an aggressive strain of reishi were able to grow from just coffee ground media. The reishi strain was the only mushroom productive enough to produce fruit. Although most these species were able to grow on pure coffee grounds, the quality of the mushrooms were lacking in marketability and were stunted or did not set fruit at all. This is likely due to the limited diversity of nutrients in the coffee substrate. Wood shavings were sourced from the campus wood workshop, operated by the University’s Department of Architecture and Product Design, in order to supplement a better ratio of nutrients. Due to the diversity of mushroom species and the different needs in nutrient ratios, trials were conducted to find the ideal balance of coffee grounds and wood shavings that would facilitate the best rate of growth in fungal mycelium before attempting to fruit them. Further experimental trials of pH levels and substrate moisture content were also performed to measure their effects on growth rates. All species of mushrooms tested in the trials included: 2 different strains of Pleurotus sp. mushrooms (Blue Oyster, and a locally found strain of Pearl Oyster), Ganoderma lucidum (Reishi), Grifola frondosa (Maitake, or “Hen of the Woods”), Lentinula edodes (Shiitake), Flammulina veluptipes (Enokitake), Pholiota nameko (Nameko), Stropharia rugosoannulata (King Stropharia), and Hericium erinaceus (Lion’s Mane).
Summary/Accomplishments (Outputs/Outcomes):
The outputs of the project include 1) compost, 2) gourmet mushrooms, 3) report, and 4) tri-folds. The outcomes of the project so far include: 1) diversion of compostable material, 2) educating the community, 3) cultivation research on gourmet mushrooms, and 4) documented progress of the Radina’s pilot study. The results so far have been measured by determining how much organic waste was able to be diverted and composted instead of being landfilled, as well as how many different types of gourmet mushrooms can be grown from spent coffee ground substrate. Formative and summative calculations were completed on the pilot study to determine the degree of success so far.
A sorting station was implemented at Radina’s Coffeehouse & Roastery with three options available: 1) compost, 2) recycle, 3) landfill. The sorting station had four bins to sort out these three options with two of the bins dedicated to recycling. Each bin included in the sorting station was equipped with a sign labeling the bin with words as well as pictures of what items should be disposed of in each bin. The signs implemented at the sorting station helped to educate customers about what items can be composted and recycled. The signs used simple, stencil-like pictures in order to appeal to foreign students who have trouble reading English. The signs show customers that there are few items that truly need to be landfilled.
Unfortunately, challenges were experienced with the sorting station due to a recent change from a recycling system that required the waste separation of each item to a “one-stopdrop” single-stream recycling system campus wide. Simply converting the existing waste sorting station at the coffee shop to have three options for waste, but having four available receptacles with openings of different size and shape (two receptacle options being single-stream recycling bins) added confusion for many customers attempting to sort their waste. Others looked at the signs and were unsure of what to do so they landfilled their waste anyway. To aid in education, composting ambassadors were introduced to the pilot study. The composting ambassadors were volunteer students who were stationed directly next to the sorting station for a two-week period, to educate confused customers on how the sorting station worked. Many customers explained that there were too many bins and that the system is confusing.
The mushroom research for this project has thus far determined the following: 1) the substrate ratio of 75% coffee and 25% wood shavings consistently showed the highest rates of growth for reishi, blue oyster, and shiitake, 2) the substrate mix of 25% coffee and 75% wood shavings facilitated the greatest growth rate for pearl oyster and 3) the moisture content in the growing substrate had high positive correlation to mycelia growth rates and affected the growth radii throughout the trials greatly.
Conclusions:
To add to the success of this pilot study, it is essential to give the people fewer and clearer options. It is ideal to reconstruct the sorting station to offer only one receptacle: 1) composting, 2) recycling, and 3) landfill. The receptacles should be uniformly sized and the outer rim of the opening for the receptacle should be labeled and color-coded: 1.) green for compost, 2.) blue for recycling, and 3.) brown or black for landfill. The availability of fewer options will add to the success of this study by giving customers simpler solutions to sorting their waste.
For mushroom production, it is critical to keep the coffee grounds as clean as possible during transportation, and grounds should not be exposed to open air. Sterilization of the mixed substrate containing coffee grounds is critical due to the media’s high susceptibility to contamination. Controlling contamination of the growing substrate and mycelium stock revealed to be the most important aspect for the success of the experimental trials and caused much delay in producing data. It was discovered later during the trials that much of the stock mushroom species were contaminated and were unfit for use. This limited the current usable species for the experiments to reishi, shiitake, blue oyster and pearl oyster. For the growth rate of the mycelium, varying levels of moisture in the substrate affected proliferation greatly. This suggests that moisture levels of the substrate have just as much influence, if not more, on growth rates than substrate mixtures.
Supplemental Keywords:
waste reduction, sustainable development, community-based, education, sustainable industry/business, pollution prevention, environmental sustainability, waste minimization, waste management, resource recovery, composting, edible mushrooms, coffee groundsRelevant Websites:
Back to the Roots ExitEspresso Mushroom Company Exit
The perspectives, information and conclusions conveyed in research project abstracts, progress reports, final reports, journal abstracts and journal publications convey the viewpoints of the principal investigator and may not represent the views and policies of ORD and EPA. Conclusions drawn by the principal investigators have not been reviewed by the Agency.