Food Waste Disposal Research Articles

Conversion of food waste to renewable energy: A techno-economic and environmental assessment

Increasing quantities of food waste have become a concern due to high disposal costs in landfills and high greenhouse gas emissions. With this increase in food waste generation, there is also an increasing demand for renewable natural gas to supplement traditional fossil fuel combustion and offset the impacts of climate change. Collecting food waste from landfills and turning it into renewable natural gas using anaerobic digestion could be a win-win option for both food waste disposal and renewable energy production. While some literature exists on the energy potential, economic feasibility, and environmental benefit of food waste disposal via anaerobic digestion, no existing study simultaneously evaluates the energy, economic and environmental effect of food waste to renewable energy via anaerobic digestion, especially on a plant and city scale. This study is focused on the techno-economic and environmental assessment of food waste to energy via anaerobic digestion in order to fill this gap. Four anaerobic digestion pathways are considered in this study: flare, pipeline natural gas, combined heat and power, and combined cycle for efficient power generation. Using a city of 1 M people the results show that renewable natural gas from food waste could supply the natural gas usage for 1.9% of residential use, 2.7% of commercial use, 1.1% of industrial use, 167.5% of the compressed natural gas vehicle fleet, 0.7% of electric power generation, or 2.5% of industrial high-temperature heating processes. All pathways except pipeline natural gas will have a positive net present value in the baseline scenario, and the pipeline natural gas pathway will become economically viable with a net present value of 31 USD/t of food waste with renewable energy credits. Lastly, all of the pathways achieve negative greenhouse gas emissions, which indicates that anaerobic digestion is a more environmentally friendly method for the handling of food waste than landfills.

Improving the Utilization of Food Waste: Conversion of Food Waste into Residual Food Dried Substance and Use of This Material as a Culture Nutrient for Microbial Production of Lactic Acid.

To reduce food waste (FW) disposal costs, many Koreans now convert FW into residual food dried substances (RFDS) using a house-service food drying machine and then dispose of the RFDS. To recycle RFDS, we tested whether RFDS could be used as a culture nutrient to produce value-added microbial chemicals. As a case study, we attempted to produce lactic acid (LA) by cultivating lactic acid bacteria using RFDS. To prepare the culture medium for LA production, we finely ground the RFDS and dissolved it with CaCO3, a pH-controlling agent. Six lactic acid bacteria were tested to improve LA production, with Lactococcus lactis showing the highest LA production. To enhance LA production, three hydrolytic enzymes, amylase, protease, and lipase, were introduced separately or simultaneously into the RFDS medium during the cultivation of the L. lactis strain. The addition of amylase alone was the most effective in increasing LA production. We then investigated the effect of the RFDS concentration on LA production. The highest LA production was achieved when 100g/L of RFDS was used. LA production was scaled up using a 5L bioreactor. During the fermentation, LA production improved to 46.32g/L, which was 1.73-fold higher than that (26.83g/L) obtained from the flask culture. These results show that RFDS from FW can be used as a culture nutrient to produce LA. Our study provides a new and simple FW recycling method and lays the foundation for expanding the usability of FW.

Eco-compensation quantification of sustainable food waste management alternatives based on economic and environmental life cycle cost-benefit assessment

Eco-compensation can promote sustainable food waste management alternatives. However, a comprehensive quantification method is not yet available. This study proposed a method to quantify the eco-compensation for food waste management through environmental and economic life cycle cost-benefit analysis. This method was tested with four food waste management alternatives in Suzhou, China, including Biological Drying + Aerobic Composting (BDAC), Anaerobic Fermentation (AF), Anaerobic Fermentation + Digestate Composting (AFDC), and INcineration (IN). According to the method, the environmental benefits (net positive externalities) and the economic loss (net negative internalities) could provide references to the government and the food waste producers (polluters), respectively, as eco-compensations for food waste disposal plants. The results suggest that AFDC (with higher energy and material recovery level) was the most environmentally and economically viable food waste management alternative. The AFDC exhibited the highest net environmental benefits (CNY t−1) of 844, followed by BDAC (596), IN (449), and AF (356). The net economic profit (CNY t−1) without subsidy of AFDC (55) was the highest, followed by IN (−5), AF (−27), and BDAC (−422). The total values of eco-compensations by the government and the polluters were 564, 101, 0, and 57 CNY t−1 for BDAC, AF, AFDC, and IN, respectively. The proposed methods for food waste disposal management can promote the effective and efficient use of government funds for the sustainable development of the food waste management sector.

Prepared compost from food waste effectively increased onion production under sub-tropical conditions

Food waste disposal is regarded as a source of contamination in the environment. There is little information on whether food waste compost can be used in agriculture, especially in the subtropics. The study examined the effect of food waste compost on onion (Allium cepa L) cultivation under an open experimental field condition in a subtropical climate. Standard methods were used to analyze the soil physicochemical parameters (pH, electrical conductivity, total dissolved solids, soil moisture, water holding capacity, total organic matter, phosphorus, potassium, manganese, iron, copper, and zinc) of control and treatment plots. Standard methods were used to measure all other morpho-physiological parameters. The plant height, the number of leaves per plant, the length and width of the leaves, the neck diameter, the relative water content of the leaves, the ash content of the leaves, and the root length were all measured. The treatment group had higher soil fertility than the control group. During the experiment, plant height, leaf number, leaf length, and leaf width all increased. Most morphophysio-chemical parameters in the treatment group onion plants were higher than in the control group after harvest. The yield of control plots was 13.64 t ha−1 and the yield of treatment plots was 32.04 t ha−1. Therefore, from this study it might be concluded that the compost from food waste has the potency to increase the soil fertility followed by the higher onion production. Hence, food waste can be used to prepare compost for higher onion production under sub-tropical conditions.Graphical

Closing the food waste loop: Analysis of the agronomic performance and potential of food waste disposal products

The recycling of urban food waste (FW) is of great importance to the sustainable and low-carbon urban development. Focusing on the solid residues of FW aerobic composting and anaerobic digestion, this study selects three FW disposal products (FWDPs) and compares their nutrient compositions with the main traditional organic fertilizers in China through a literature review; carries out a seven-season field experiment with 30% of the nitrogen in FWDPs substituted for equal chemical nitrogen to explore the impacts on vegetable yields; and uses a field questionnaire to investigate farmers' awareness of FWDPs. FW aerobic compost and FW digestate solid residue can significantly increase seven-season total yields by 21.5% and 17.2% respectively compared with conventional chemical fertilizer alone, and maintain the same yield level with conventional combined application of chicken manure and chemical fertilizer, proved to be effective on crop yield as organic fertilizers. The case study of Xiamen indicates that FWDPs have great potential to produce organic fertilizers and reduce the application amount of pure chemical fertilizers by 5.6% under current conditions, where around one-third of restaurant FW is disposed of using anaerobic digestion technologies. Measures like formulating supportive regulations, expanding government propaganda, and producing qualified and cost-effective commercial organic fertilizers with FWDPs will improve farmers’ knowledge and acceptance of FWDPs.

Effective multipurpose sewage sludge and food waste reduction strategies: A focus on recent advances and future perspectives

Energy crisis and increasing rigorous management standards pose significant challenges for solid waste management worldwide. Several emerging diseases such as COVID-19 aggravated the already complex solid waste management crisis, especially sewage sludge and food waste streams, because of the increasingly large production year by year. As mature waste disposal technologies, landfills, incineration, composting, and some other methods are widespread for solid wastes management. This paper reviews recent advances in key sewage sludge disposal technologies. These include incineration, anaerobic digestion, and valuable products oriented-conversion. Food waste disposal technologies comprised of thermal treatment, fermentation, value-added product conversion, and composting have also been described. The hot topic and dominant research foci of each area are summarized, simultaneously compared with conventional technologies in terms of organic matter degradation or conversion performance, energy generation, and renewable resources production. Future perspectives of each technology that include issues not well understood and predicted challenges are discussed with a positive effect on the full-scale implementation of the discussed disposal methods.

Household food waste disposal behaviour is driven by perceived personal benefits, recycling habits and ability to compost

Households are responsible for a large proportion of total food waste and are an important focal point for addressing food waste disposal issues. Determinants of household food waste minimisation behaviour have been previously explored; however, little is known about the determinants of household food waste disposal behaviour. Several food waste disposal options are available to households, depending on context, with some disposal practices being more sustainable than others. This study applies the food waste hierarchy to household food waste disposal behaviour and identifies three sustainable food waste disposal behaviours (sorting food waste into the green organics bin, reusing food waste for animal feed, and home composting); and three unsustainable behaviours (disposing of food waste in the general waste bin, the recycling bin, and/or the sink). Using data from a survey of 1027 respondents, a fractional multinomial logit model is used to analyse the associations between explanatory variables and sustainable versus unsustainable household food waste disposal behaviour. Having a kitchen caddy is associated with increased sustainable food waste disposal behaviour (higher proportion of food waste diverted to the green bin and composted). Key factors that drive households' use of kerbside green organics bins are perceived personal costs and benefits, and recycling habits. Importantly, environmental self-identity is positively associated with home composting practices. Factors associated with a higher proportion of food waste disposed of in the general waste bin (unsustainable behaviour) include stronger perceived inconvenience of using the green bin, living in a unit, and having a higher household income. Findings from this study can provide insight into interventions to promote more sustainable household food waste disposal practices.

Trophological approach in the development of nutrition theories

This article presents a trophological approach to the development of nutrition. The evolution of human views on nutrition from antiquity to the present time, including issues of perfect nutrition, is considered. The main concepts of nutrition theories are formulated. The systematized reasoning is useful for new rationale for solutions of challenges related to optimization of nutrition. Within the scope of the development of nutrition theories, the problem of perfect food plays a special role. The article presents a modern vision of perfect nutrition. The designing of trophological nutrition algorithm is based on scientific approaches that both to justify the correct consumption of food products, and also define the most reasonable way of their production, storage, distribution and disposal of food waste. The implementation of the trophological approach in theories of nutrition is also reflected in the concept of the state policy of the Russian Federation in the field of healthy nutrition among the population. This topic is also relevant in light of the sharp increase of food allergies among the various groups of population, because people who suffer from food allergies must follow a special diet to prevent the risk of allergic reactions, which can be managed using a nutritional approach.

Preparation of Ce/ferroferric oxide/food waste‐derived biochar for aqueous Cr(VI) adsorption

AbstractBACKGROUNDCr(VI) in aqueous solution is a serious concern that can harm human health by accumulating in the food chain. Meanwhile, the most common form of food waste (FW) disposal by landfill takes up a lot of area and pollutes the environment. As a consequence, FW was employed as a raw material in the production of food waste‐derived biochar (FWB), which was then modified to produce a Ce/Fe3O4/FWB composite for high‐efficiency Cr(VI) removalRESULTSThe structure, morphology, and properties of the Ce/Fe3O4/FWB composite were thoroughly investigated, as well as its Cr(VI) adsorption ability. The composite exhibited the highest Cr(VI) adsorption of 20.4 mg/g at pH 2. Furthermore, the adsorption fitted the pseudo‐second‐order kinetic model and the Langmuir model, with intra‐particle diffusion acting as the rate‐controlling step. The thermodynamic investigation demonstrated that Cr (VI) adsorption by Ce/Fe3O4/FWB was a spontaneous endothermic process. With increasing concentrations of Cl−, SO42− and PO43−, the Cr(VI) adsorption was weakened in the sequence of Cl−, SO42− and PO43−.CONCLUSIONAdsorbent preparation utilizing FW as raw material is a sustainable and environmentally beneficial method for FW reclaimation and Cr(VI)‐bearing wastewater treatment. © 2022 Society of Chemical Industry (SCI).

The Distribution of Temperature on Aerobic Composting of Food Waste: Experimental studies and CFD analysis.

Food waste generation has a significant impact on the economy, society, and environment. Indonesia as the second-largest contributor of food waste, face this problem. Food waste generation increased for 20 years and contributed to more than 40% of solid waste in Indonesia. The government has a strategy to reduce the generation and disposal of food waste in landfills. One of the methods used is by recycling used composting. The composting method that is usually used is aerobic composting. Several factors affected the process and the rate-limiting step in oxygen concentration. This paper aims to analyze the effect of oxygen on the temperature during composting. Temperature is one of the parameters that could be used to analyze the process and determine the maturity of compost.The research in this paper utilized CFD modeling to describe the dynamic changes and spatial distribution of temperature in the aerobic composting process using mass-heat-momentum coupling based on microbial mechanisms. The equations used are based on several previous research and journals. Composting experiments were carried out with the aeration method at intervals to verify the proposed model. The microorganisms’ growth affects oxygen concentration which then affects the temperature distribution of the composting process. The simulation results show that the model accurately predicts the dynamic temperature changes and their distribution on the composting substrate. The proposed CFD model shows promising results and simulates the actual working conditions of the aerobic composting process.

Sustainable Food Waste Recycling for the Circular Economy in Developing Countries, with Special Reference to Bangladesh

Food waste management is a critical environmental issue in many developing countries, including Bangladesh, due to unplanned food waste disposal and lack of dedicated food waste legislation. In those countries, a significant amount of food waste is discarded to the environment rather than being recycled. In Bangladesh, food waste is traditionally often used for composting, landfilling, and feeding animals, as there is no valorization option. In addition, food waste and food waste streams of food industries are utilized for the recycling and production of diverse economically valuable bioactive compounds. Therefore, we conducted a detailed literature review on food waste management and valorization options in Bangladesh and discussed the findings in the context of global status. The amount of food waste in Bangladesh is quite high, and it needs to be recycled to promote the circular economy of this developing nation. In this study, it is revealed that various research uncertainties and gaps regarding sustainable food waste management exist in Bangladesh, which should be investigated as priority research. Furthermore, a logical and global synchronization of the contemporary approach to food waste valorization with policy advocacy is proposed, to ensure efficient food waste decontamination and recycling in Bangladesh. This is the first and most comprehensive evaluation of the present research trend and prospects for sustainable recycling of food waste for the circular economy of Bangladesh.

Dehydrated Food Waste for Composting: An Overview

Food waste disposal has recently received much attention worldwide due to its major impact on environmental pollution and economic costs. Using high moisture content of food waste has the highest negative environmental impact due to increased greenhouse gas emissions, odor, and leachate. Drying technologies play an important role in reducing the moisture content of food waste, which is necessary for environmental sustainability and safety. The first part of this review highlights that sun-drying is the most cost-effective drying method. However, it has not been widely recommended for food waste management due to several limitations, including the inability to control sunray temperature and the inability to control end-product quality. Thermal drying eliminates moisture from food waste quickly, preventing hydrolysis and biodegradation. Thermal dryers, such as the GAIA GC-300 dryer, and cabinet dryer fitted with a standard tray, are the best alternative to sun drying. The second part of this review highlights that dehydrated food waste products are slightly acidic (4.7–5.1), have a high electrical conductivity (EC) value (4.83–7.64 mS cm-1), with high nutrient content, due to low pH levels, dehydrated food waste is not suitable for direct use as a fertilizer for the plants. So, the dried food waste should be composted before application to the plants because the composting process will dominate the limitation of phytotoxins, anoxia, salinity, and water repellence. Trench compost can be a good choice for decomposing dried organic waste because trench compost relies solely on soil decomposing microorganisms and insects.

Energy and carbon footprint analysis of municipal wastewater treatment process integrated with food waste disposer

Household food waste (FW) management has become an emerging environmental issue affecting sustainable urban development. The application of in-sink domestic food waste disposers (FWDs) have brought significant public attentions due to its simplified waste handling process and reduced household expenses. However, the potentail negative impacts of mixing FW in the sewer system, i.e., the reduction of aeration efficiency in wastewater treatment processes (WWTPs) and corresponding increase of greenhouse gas (GHG) emission, has not been quantified. In this study, real-time oxygen transfer efficiency in processing water was measured in WWTPs receiving negligible amount of FW and compared with those receiving sewage combined with FWD effluent. WWTP receiving sewage with FW had 6–10% lower oxygen transfer rate than those without FW, resulting in extra energy consumptions of 0.25–0.30 kWh/m3 and GHG emissions of 0.35–0.41 kg CO2/m3. For estimating the substantial impacts of FWD to the carbon cycle, sludge treatment scenarios were designed among anaerobic digestion (AD), incineration, and direct landfill disposal. Compared with AD (−0.07 kWh/kg) and incineration (0.112 kWh/kg), FWD/WWTP consumed more energy (0.69–0.9 kWh/kg) and most of which (∼64%) was required by aeration. The operating costs of WWTPs also increased by 1.6–2.1 times in comparison with those did not receive FW. The application of FWD, however, could reduce the overall GHG emissions by 35.2% in comparison with direct landfilling. Decision-makers should guide householders and waste management practitioners through new policies such as carbon credits and/or waste charging scheme to support more environmental-friendly disposal methods of FW, especally when the maturity of socio-economic conditions are of concerns. Compared with AD and incineration, FWD may be a compromising alternative to control GHG emissions with existing wastewater treatment facilities especially to those regions where complete FW classification and treatment are not well-established.

Hydrothermal treatment: An efficient food waste disposal technology.

The quantities of food waste (FW) are increasing yearly. Proper disposal of FW is essential for reusing value-added products, environmental protection, and human health. Based on the typical characteristics of high moisture content and high organic content of FW, hydrothermal treatment (HTT), as a novel thermochemical treatment technology, plays unique effects in the disposal and utilization of FW. The HTT of FW has attracted more and more attention in recent years, however, there are few conclusive reviews about the progress of the HTT of FW. HTT is an excellent approach to converting energy-rich materials into energy-dense fuels and valuable chemicals. This process can handle biomass with relatively high moisture content and allows efficient heat integration. This mini-review presents the current knowledge of recent advances in HTT of FW. The effects of HTT temperature and duration on organic nutritional compositions (including carbohydrates, starch, lipids, protein, cellulose, hemicellulose, lignin, etc.) and physicochemical properties (including pH, elemental composition, functional groups, fuel properties, etc.) and structural properties of FW are evaluated. The compositions of FW can degrade during HTT so that the physical and chemical properties of FW can be changed. The application and economic analyses of HTT in FW are summarized. Finally, the analyses of challenges and future perspectives on HTT of FW have shown that industrial reactors should be built effectively, and techno-economic analysis, overall energy balance, and life cycle assessment of the HTT process are necessary. The mini-review offers new approaches and perspectives for the efficient reuse of food waste.

Bioconversion of Starch Base Food Waste into Bioethanol

The global demand for fuel keeps increasing daily. The massive depletion of fossil fuels and their influence on the environment as pollution is a severe problem. Meanwhile, food waste disposal is also a complex problem in solid-waste management since one-third of every food consumed is discarded as waste. The standard waste management methods, including food waste incineration and landfilling, are considered hazardous to the environment. Food waste constituents are majorly starch-based and contain various biomolecules, including sugar, lipids, proteins, vitamins, cellulose, etc. These polysaccharides can be hydrolysed into monosaccharides such as glucose, which can then be fermented using microorganisms to produce ethanol through the fermenting of sugars derived from enzymatic hydrolysis treatment of food wastes. The human food system is rich in starch, which can be a potential resource for bioethanol production.

Environmental impacts and nutrient distribution routes for food waste separated disposal on large-scale anaerobic digestion/ composting plants.

Centralized biological treatments, i.e., anaerobic digestion (AD) and in-vessel composting (IVC), were supposed to be the promising processes for the disposal of food waste (FW) after source separation, while the systematic benefits were unclear for FW with high water content, salt and oil and thus influenced the selection by the local decision-makers. In this study, two large-scale working AD and IVC plants were compared for environmental impacts, nutrient recovery and economic benefits. For unit amount of FW, 89.26kg CO2-eq was released in IVC mainly due to 47.89kWh electricity consumption, and 57.02kg CO2-eq was produced in AD. With the application of compost and energy recovery, 26.88 and 93.55kg CO2-eq savings were obtained in IVC and AD, respectively. NH3 emissions were the main contributor to acidification (0.35kg SO2-eq) in IVC, while AD exerted less impact on acidification (0.09kg SO2-eq) and nutrient enrichment (0.25kg NO3-eq) attributed to the counteract of energy recovery. 2029 would be the inflection point for global warming potential in AD with more clean energy applied in electricity mix in China. For nutrient recovery, more C (8.3%), N (37.9%) and P (66.7%) could be recovered in compost, while those were discharged via leachate and biogas residue in AD. The cost of IVC was 16 CNY/t (2.40 USD/t) lower than AD. Combing the three key indexes and the sale routes of products, IVC was recommended to be used in areas dominated by agriculture and forestry industries, and AD was more suitable for large cities.

Capabilities, opportunities and motivations that drive food waste disposal practices: A case study of young adults in England

Data in England suggests that food waste is still being disposed into the black bin, also known as residual waste, despite continuous efforts to promote separate food waste collection and food waste reduction practices. Furthermore, it has been anecdotally reported that 18 to 30-year-olds have the highest propensity to generate large amounts of food waste and thus need to be urgently engaged in communication that helps them change their behaviour. This study aims to explore young adults' capabilities (C), opportunities (O), and motivations (M) that may lead to a certain behaviour (B) towards food waste disposal practices (FWDP) grounded on the Behaviour Change Wheel, also called the COM-B model, and could reveal barriers to action. In doing so, a case study approach is used via Harrow Council residents in England within the age group of 18–30 years old. The study took place amid the national lockdown due to the Covid-19 pandemic and targeted young residents within the 18–30 age group using a structured interview approach with a diagnostic questionnaire promoted through Harrow Council's social media account, followed by in-depth interviews with eligible participants. Out of the 30 residents who completed the diagnostic questionnaire, 35% reported no FWDP, 42% partial FWDP (i.e., some incorrect items in the black bin waste), and 23% reported engaging in FWDP. The first two groups only were invited to the online interviews. The interview results are organised using the COM-B model and reveal that: 1) due to Covid-19 there was a shift to home cooking and increased food waste generation (B); 2) there is a lack of FWDP knowledge, information on benefits, and advice on alleviating pests/health concerns from councils, whereas FWDP differences between councils and reliance on ‘common sense’ often create confusion around FWDP (C); 3) the council may not always provide a caddy or a drop-off/collection service, whereas economic (caddy liners purchase) and logistic concerns (e.g., the lack of a regular collection schedule, unfavourable features of the caddy, and lack of prompts/reminders) resulted to limited uptake of FWDP as the norm (O); 4) the benefits of FWDP do not outweigh costs, while feelings of disgust and a sense of inconvenience lead to lack of or partial FWDP (M). To our knowledge, this is the first study using the COM-B model within the context of FWDP and with a specific focus on young adults in England. Novel theoretical and practical insights are discussed, along with limitations and future research directions.

Chitinase enzyme in bacterial species and fungal growth inhibition against A. niger and Penicillium

Chitin is the most abundant polysaccharide in nature, second after cellulose as it found in the structure of crustaceans, insects and fungi being a significant component. Sea food waste disposal pose a great problem as chitin in nature degrade at a very gradual rate. Efforts are being made to use chitinase enzyme from different organisms to increase the rate and efficiency of chitin waste disposal. Moreover, chitinase and chitinase producing bacteria are widely being exploited to be used as bio-control agents to inhibit crop pathogens. On the basis of its mechanism of action, chitinase can either be endochitnase or exochitinase. Endo chitinases randomly hydrolyses internal glycosidic bonds in chitin. Exochitinase is exoglycosidase that can be divided into two subtypes based on the specificity of their action Chitinase is synthesized by a number of different microbes including bacteria, fungi and other organisms like mammals, insects etc. This paper gives information about the production of different chitinase enzymes from different bacterial gram-positive species. Antifungal activity for different isolates were tested against A. niger and Penicillium. The isolates showed varying degree of fungal growth inhibition against different fungi.

Different stages of microbial community during the anaerobic digestion of food waste.

Large-scale food waste (FW) disposal has resulted in severe environmental degradation and financial losses around the world. Although FW has a high biomass energy contents and a growing large number of national projects to recover energy from FW by anaerobic digestion (AD) are being developed. AD is a promising solution for FW management and energy generation when compared to typical disposal options including landfill disposal, incineration, and composting. AD of FW can be combined with an existing AD operation or linked to the manufacture of value-added products to reduce costs and increase income. AD is a metabolic process that requires four different types of microbes: hydrolyzers, acidogens, acetogens, and methanogens. Microbes use a variety of strategies to avoid difficult situations in the AD, such as competition for the same substrate between sulfate-reducing bacteria and methane-forming bacteria. An improved comprehension of the microbiology involved in the anaerobic digestion of FW will provide new insight into the circumstances needed to maximize this procedure, including its possibilities for use in co-digestion mechanisms. This paper reviewed the present scientific knowledge of microbial community during the AD and the connection between microbial diversity during the AD of FW.

Facilitating solid-state anaerobic digestion of food waste via bio-electrochemical treatment

Food waste has become a global environmental concern over emissions of greenhouse gas and odorous pollutants. Anaerobic digestion is gaining increasing attention as an effective food waste disposal method combining waste minimization and bioenergy recovery. Solid-state anaerobic digestion can handle food waste containing high contents of solids and has the merits of higher disposal volumes and less parasitic energy input, however, the low energy/mass transfer impairs the treatment efficiency. This study incorporated bio-electrochemical treatment into solid-state anaerobic digestion of food waste to overcome these shortcomings for enhanced performances. Food waste liquid leachate was used as feedstock to validate the bio-electrochemical treatment effects under different conditions. At a low applied voltage of 0.7 V and initial pH of 8.13, the methane yield increased by 77.5% while the carbon dioxide yield decreased by 16.0% compared with the control without electrodes. Although higher voltages (1.1–2.0 V) contributed to higher methane and hydrogen yields, the fast consumption and breakages of anodes significantly decreased the treatment consistency and material lifespan. Thereby, 0.7 V was selected as the applied voltage when incorporating the bio-electrochemical unit into the solid-state digester treating food waste. Cathodic hydroxide generation increased the buffering capacity, thus contributing to a more stable start-up process. With an immersed electrode surface area of 25.2 cm2/L, the highest methane yield of 526.7 mL/gVS was recorded with lower carbon dioxide and hydrogen contents initially, and the peak gaseous hydrogen sulfide emission was significantly reduced by 71.5% mainly due to the ferrous ions release from low carbon steel anode for sulfide precipitation.