The primary aim of this project was to develop an integrated non-GMO strategy for (i) production of high value products, (ii) generation of bioethanol, and (iii) generation of renewable energy in the form of biogas from vegetable, fruit and confectionery wastes (VFCWs) and source-separated OFMSW. In the project, a range of novel, optimized and low-cost thermostable enzyme cocktails (thermozymes) were developed from generally regarded as safe fungal sources and used as eco-friendly biocatalysts to convert carbohydrate-rich processed and unprocessed vegetable, fruit and cereal residues to soluble sugar rich syrups and fractions rich in other high-value bioactive molecules. Maximum sugar yields were obtained (>66-90% hydrolysis) at 70-80oC with gentle agitation throughout the enzyme treatment process. Other reaction parameters, such as pH, reaction time and moisture content were dependent on the thermozyme cocktailwaste combination. Of the wastes treated, >68-91% of the sugars released were monosaccharides (or simple fermentable sugars). The relative amounts and types of monosaccharides varied depending on the waste (i.e. mixed vegetable waste, mixed breads, carob waste, apple pomace/pulp, mixed fruit residues, mixed cereals/cereal fractions, biodegradable packing, catering waste paper and card, coffee waste, spent tea bags/tea leaves, etc.). The enzyme cocktails and reaction conditions can be readily optimized for a wide variety of waste feedstocks. The results highlighted the low-cost and highly efficient properties of the thermozymes in that very low dosages of enzyme cocktail were required. While enzyme recovery was investigated, the economic advantages of enzyme recovery would be out-weighed by the cost of any recovery system.



The potential of utilising thermophilic digestion in the second stage of the thermozymeanaerobic technology process was clearly proven in this study. Rapid start up of the 9 thermophilic reactor R1 was achieved using mesophilic granular inoculum. In response to increased loading rates, the thermophilic reactor was more susceptible to the build up of intermediate VFAs, however, the thermophilic granules were demonstrated to be more robust than mesophilic granules. During the application of thermozyme hydroysates the thermophilic reactor performed comparably, and during some periods, exhibited superior performance to the mesophilic reactor. Remarkably, the biomass in both reactors retained the capacity to readily degrade sugars which they had not been exposed to for some time. It was found that the application of thermozyme hydrolysate improved the capacity of the reactors to degrade all sugars tested. In contrast to other reports in the literature, thermophilic AD was found to be very stable and not subject to substrate inhibition. In addition, the sugar-rich hydrolysates were shown to be good feedstocks for the production of other bio-fuels such as bioethanol by yeast fermentation, and other highvalue products (e.g. chemical feedstocks and natural antioxidants). A preliminary study was conducted to evaluate key hygiene aspects of the reaction processes with respect to microbial pathogen kill-rates. This study was important to investigate if the thermozyme- AD process could meet the highest environmental and public health standards, thereby ensuring higher value and a greater diversity of end-use for the reaction products. The effects of pre-sanitation at 55oC (temperature for thermophilic AD) and 70oC on the survival of faecal indicator organisms was investigated to assess the efficiency of hygienisation (and/or a treatment step). Sewage sludge was used as substrate with Escherichia coli, Enterococci, Salmonella seftenberg and Clostridium perfringens as test indicator species. While the results represent preliminary findings, at 70oC, both E. coli and S. seftenberg were very susceptible to the increased temperature and could not be detected after <5 min. While the Enterococci counts were markedly reduced after 5 min at 70oC, but remained constant for the remaining 55 min. The results suggest that a longer treatment time at 70oC, or a higher treatment temperature (e.g. 80oC), both of which are compatible with the enzyme technology, may be more appropriate to ensure complete kill-off of the Enterococci and C. perfringens. To protect the thermozyme technology, the source organism(s) and key applications, a PCT has been filed to protect the thermozyme 10 technology, the source organism(s) and key applications. Scale-up of thermozyme production is in progress and plans to develop the combined technologies at pilot scale are envisaged. This study has revealed the potential of the thermozyme-AD technology to provide a simple, efficient and low-cost option for waste management and energy recovery from non-animal food wastes.

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Tuohy, M. Colleran, E.   "Waste - A Biotechnological System for Production of Value-added products, Bioethanol and Methane from Non-animal Food Wastes". Associated datasets and digitial information objects connected to this resource are available at: Secure Archive For Environmental Research Data (SAFER) managed by Environmental Protection Agency Ireland https://eparesearch.epa.ie/safer/resource?id=1147b2fd-24cb-102d-8e25-e9973852f3cf (Last Accessed: 2025-01-20)

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SAFER-Data Display URL	https://eparesearch.epa.ie/safer/iso19115/display?isoID=131
Resource Keywords	ntegrated non-GMO Bioethanol Methane wastes biogas thermostable enzyme cocktails thermozymes sugar carbohydrate
EPA/ERTDI/STRIVE Project Code	2001-WMF-LS-7/7
EPA/ERTDI/STRIVE Project Theme	Waste and Resource Management
Resource Availability:	Public-Open
Limitations on the use of this Resource	n the event of obtaining access to datasets corresponding to this resource any datasets, data, or information resources being used in a journal article or other means of publication the original authors should be informed of this usage and an appropriate acknowledgement or citation is included within the published article. The EPA advise that this acknowledgement should take one of the following forms dependent upon how heavily the published work relates to the downloaded data: * Co-Authorship(s) for the original author(s)* Written acknowledgement within the body of the article* Written acknowledgement by means of the inclusion of a bibliography entry which clearly cites the original authors.
Number of Attached Files (Publicly and Openly Available for Download):	1
Project Start Date	Thursday 1st February 2001 (01-02-2001)
Earliest Recorded Date within any attached datasets or digital objects	Thursday 1st February 2001 (01-02-2001)
Most Recent Recorded Date within any attached datasets or digital objects	Wednesday 1st February 2006 (01-02-2006)
Published on SAFER	Tuesday 17th November 2009 (17-11-2009)
Date of Last Edit	Tuesday 17th November 2009 at 14:39:35 (17-11-2009)
Datasets or Files Updated On	Tuesday 17th November 2009 at 13:07:22 (17-11-2009)

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The following is a list of projects, datasets, and resources on SAFER-Data from which users downloaded attachments from soon after downloading attachments from this resource Waste - A Biotechnological System for Production of Value-added products, Bioethanol and Methane from Non-animal Food Wastes. You can view the full description for projects, datasets, and resources by using the links supplied.

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• Energy Efficiency Improvement of Waste Water Treatment Processes Using Process Integration Techniques View Full Metadata Description
• Critical Analysis of the Potential of Mechanical Biological Treatment for Irish waste Management View Full Metadata Description
• Environmental Sustainability and Future Settlement Patterns in Ireland View Full Metadata Description

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