The quantity and composition of household food waste during the COVID-19 pandemic: A direct measurement study in Canada

Systematic review of factors influencing household food waste behaviour: Applying the theory of planned behaviour

Globally, household food waste alone accounts for about $700 billion in environmental costs owing to the resources expended in producing discarded or uneaten food, along with social costs reaching approximately $900 billion. Reducing this waste by 25% could potentially feed 821 million chronically undernourished individuals. This systematic review examines household food waste behaviour using the Theory of Planned Behaviour (TPB). Comprehensive searches were conducted in PubMed and EMBASE using Elsevier supplemented by additional articles from the reference lists. The procedure followed the PRISMA flowchart. A descriptive analysis was conducted to summarize the characteristics of the 42 included studies from 17 countries. Significantly, 95% of these articles were published between 1 January 2010 and 19 April 2024, in Scimago Q1 ranked journals. The findings demonstrate an intersection of TPB components in explaining household food waste behaviour. This study suggests that a holistic strategy targeting attitudes, subjective norms and perceived behavioural control is essential for effectively reducing household food waste. Additionally, tailored interventions that consider demographic and socioeconomic factors are necessary to address the diverse needs of different populations. The study concludes that public education targeting mindful consumption, effective policies and community initiatives can significantly reduce food waste.

Mapping quantity, composition, and embedded environmental impacts of post-consumer waste in the food service industry in China

Understanding the current state of food waste is the basis for effective interventions. Based on field research conducted for 133 days, from March to August 2022, and for 25 days in November 2022, totaling 158 days, this study obtained first-hand data on the waste and consumption of 103 food items in ten categories at sample restaurants in different regions and city levels, and of different operation sizes in China. A total of 7759 consumers were part of this study, of whom 10 % them were children. The food delivered to a total of 2538 tables was counted as part of this study, and the average number of people per table in this study was three. The research objective was to measure the quantity, composition, and environmental impacts of post-consumer waste in the food service industry at the national level. It was discovered that: (1) Food waste generated by post-consumers in China totaled 7.57 Mt, or 43.98 g per capita per meal in 2022. (2) Fruit was the most important type of waste at 1.51 Mt. (3) Roots and tubers had the highest food waste rate (53 %). (4) The annual food waste resulted in a carbon footprint of 30.67 Mt CO2-eq, a nitrogen footprint of 393.94 million kilograms (Mkg N), a phosphorus footprint of 53.87 Mkg P, a water footprint of 17.09 million litres, and a land footprint of 4.36 million hectares (Mha).

Effect of pomegranate peel powder-infused multigrain chapatti on diabetes prevention: A randomized clinical trial

Diabetes mellitus is a metabolic and chronic disease linked to lifestyle factors like dietary patterns and physical inactivity. This randomized clinical study aimed to develop a novel dietary intervention using pomegranate peel powder-based multigrain chapatti to prevent diabetes. The product was formulated by incorporating pomegranate peel powder into a mixture of wheat flour, pearl flour, millet flour, and chickpea flour. The study included the formulation of various treatments (Tc, T1, T2, and T3) following product development, and these treatments were subjected to comprehensive assessments. The nutritional composition and antioxidant potential of the pomegranate peel powder-based multigrain chapatti were analyzed. Sensory attributes, including taste, texture, and overall acceptability, were evaluated. Additionally, biochemical analyses, including blood glucose levels and HbA1C, were conducted to assess the impact of the interventions on blood glucose metabolism. The results revealed that the nutritional profile and phytochemical potential of the product improved significantly in treatment T3, which contained 15% pomegranate juice. Overall acceptability was found to be high for T3, indicating that the inclusion of pomegranate peel powder was well received in terms of taste and sensory qualities. Importantly, the clinical trial demonstrated positive outcomes in the intervention group receiving the pomegranate peel powder-based multigrain chapatti. Blood glucose analysis and HbA1C assessments indicated that the consumption of this innovative dietary product contributed to improved blood glucose metabolism, suggesting its potential as a preventive strategy for diabetes.

Food Retail Resilience Pre-, during, and Post-COVID-19: A Bibliometric Analysis and Research Agenda

This paper aims to conduct a bibliometric mapping and systematic review of the food retail industry's resilience strategy in the context of COVID-19. Specifically, we aim to identify relevant research gaps in the industry during the pre-, during, and post-pandemic periods and highlight the differences between B2B and B2C sectors. We analyzed articles in the Scopus database from 2019 to 2022 using the PRISMA method for article selection, resulting in a total of 69 articles. We employed a VOS viewer for bibliometric mapping. Our analysis revealed that most studies focused on the impact of COVID-19, with only a few examining the pre- and post-pandemic periods critically. In the B2C context, we identified two major topics: changes in purchasing and consumption behavior, and food waste and safety. In the B2B sector, the two most recurrent subjects were retailers' strategies and supply chain management. This study provides valuable insights for policymakers by exploring industry trends and for scholars by highlighting future research agendas based on the identified topics.

Reflections on COVID-19 pandemic and waste management in developing countries: A case study in São Paulo city, Brazil

COVID-19 pandemic has changed several aspects in human behaviour, whereas population mobility patterns have been strongly affected by social distancing. In parallel, changes in solid waste generation patterns have been reported worldwide. This work assessed the influence of the COVID-19 pandemic on waste generation and collection in São Paulo city, Brazil, the largest city of Latin America. Data on nine types of wastes collected between 2013 and 2021 were obtained, and the quantities of wastes collected before and during the pandemic were compared. These data were also discussed in light of data on COVID-19 cases and rates of social distancing and mobility. An increase in the amount of recyclables collected during the first wave of COVID-19 (March to September 2020) was observed. Decreases in the quantities of construction, demolition and bulky wastes (first wave of COVID-19) and farmers market wastes (second wave - October 2020 to February 2021) were also evidenced. The quantities of medical wastes collected during the pandemic significantly increased. The amount of residential wastes was lower than the mean for the pre-pandemic period during the first months of COVID-19. Thus, changes in lifestyle and consumption patterns of the population of São Paulo city seem to have affected solid waste generation during the pandemic, which reinforces the need of implementing solid waste management policies based on a diagnostic that characterise and consider these changes.

Food Safety Awareness, Changes in Food Purchasing Behaviour and Attitudes towards Food Waste during COVID-19 in Türkiye

(1) Background: The COVID-19 pandemic brought the key issues of food security, food safety, and food waste into sharp focus. Türkiye is in the enviable position of being among the top ten agricultural economies worldwide, with a wide diversity of food production. This survey was undertaken in order to gain insights into consumer behaviour and attitudes in Türkiye with respect to these issues. The objective was to highlight strengths and weaknesses, identify areas for improvement, and present strategies for the future. (2) Methods: This survey was carried out between April and May 2022 in 12 provinces throughout Türkiye. Face-to-face interviews were performed with 2400 participants representing a cross-section of ages, educational attainment, and socio-economic categories. The findings were evaluated statistically. (3) Results: The results provide an insight into attitudes and behaviours, both pre-COVID-19 and during the pandemic. In several ways, the pandemic enhanced knowledge and improved behaviour, leading to improvements in diet and reductions in food waste. However, worrying concerns about food safety persist. Specific attention has been given to understanding patterns of bread consumption, particularly in consideration of waste. (4) Conclusions: It is hoped that the results of this survey will increase dialogue between the components of the food sector, encourage education initiatives, and contribute to improving food safety and security and reducing food waste in Türkiye and beyond.

Adsorption characteristics of magnetized biochar derived from Citrus limetta peels

Agro-industrial waste is an alarming issue that needs to be addressed. Waste valorization is an effective technique to deal with such effectively. Synthesis of biochar from fruit waste is one of the emerging approaches for adsorption, energy storage, air purification, catalysis, and biogas production trending these days. Magnetized Citrus limetta biochar (MCLB) was synthesized from Citrus limetta peels and was magnetized using iron oxide. Magnetization of biochar increases its functionalities as well as makes its separation easy. The removal of Methylene Blue (MB) dye from an aqueous solution is achieved through the use of MCLB. Methylene Blue is a prominent and widely used cationic-azo dye in the textile and printing industries. The accumulation of MB in wastewater is the major problem as MB is reported as a carcinogenic agent. The removal of MB dye with MCLB was analyzed by adsorption studies, wherein the effect of factors influencing adsorption such as initial concentration of MB dye, MCLB dosage, the effect of pH, contact time, and adsorption isotherms were studied. Characterization of MCLB was carried out using various techniques, such as FTIR, VSM, XRD, SEM, RAMAN, and Zeta potential. The adsorption isotherm mechanism was well explained with the non-linear Langmuir isotherm model resulting in a good adsorption capacity (q e  = 41.57 mg/g) of MCLB when MB (co = 60 mg/L, pH ~ 6.8, T = 273K). The thermodynamics analysis revealed that MB's spontaneous and endothermic adsorption onto the MCLB surface followed pseudo-second-order kinetics. The results obtained from this study suggest that the magnetized biochar derived from Citrus limetta peels has a wide range of potential applications in the treatment of dyeing wastewater.

Characterization of household food waste in Italy: Three year comparative assessment and evaluation of seasonality effects

In the present paper, the results of the first comparative assessment of household food waste in Italy are reported with a timeframe of three years coupled with an evaluation of seasonality effects. To pursue the aim of Sustainable Development Goal 12.3 to halve consumer food waste by 2030, the Italian Observatory on Food Surplus, Recovery and Waste carried out two surveys in 2021 (July and November) to characterize household food waste and to evaluate the seasonality effects. Data were collected with a validated questionnaire. For monitoring purposes, data collected in July 2021 were compared with those collected in July 2018. In three years, waste increased from 187.2 to 203.8 g per capita per week (p = 0.00). Fresh foods such as fruits and vegetables, bread, milk, yogurt, and non-alcoholic beverages, were the most wasted. In July the level of waste was higher for fruit (p = 0.00) while in November was higher for potato products (p = 0.04), pasta (p = 0.00), rice (p = 0.04), legumes (p = 0.01), and soups (p = 0.04). Data collected in July 2021 showed that retired people (p = 0.04), families with children (p = 0.01), particularly young children (9-13 years old) (p = 0.02), wasted less while who live in large town areas (p = 0.00), people with self-perceived limited monetary resources (p = 0.01) and mono-component families (p = 0.00) wasted more. The findings of the present work showed that there are specific population groups that wasted more with a gap between the intentions and the actions. The present data have a particular value posing the roots for the establishment of a food waste surveillance system in Italy.

The dissolution of polysaccharides and amino acids enhanced lactic acid production from household food waste during pretreatment process

A large amount of household food waste (HFW) is produced yearly, resulting in environmental problems and financial burdens. Bio-production of lactic acid (LA), a high value-added platform chemical, from HFW by anaerobic fermentation is a promising way of resource recovery. However, the LA production yield from HFW is low. This paper compared several pretreatment methods (hydrothermal pretreatment, chemical pretreatment, and combined hydrothermal and chemical pretreatment) to improve LA production from HFW. The result showed that the combined pretreatment (alkali-thermal pretreatment at pH 10 and 120 °C) significantly increased the LA production than single hydrothermal and chemical pretreatment. The pretreatment process promoted the dissolution of organics, especially the polysaccharides and amino acids, and further influenced the LA production by Lactobacillus rhamnosus ATCC 7469. Among the amino acids, aspartic acid (Asp), threonine (Thr), glutamic acid (Glu), glycine (Gly), alanine (Ala), cystine (Cys), valine (Val), isoleucine (Ile), arginine (Arg), and proline (Pro) significantly correlated with LA concentration.

Optimization of food-energy-water-waste nexus in a sustainable food supply chain under the COVID-19 pandemic: a case study in Iran

Abstract

During the coronavirus epidemic, food supply chains have been affected by disruptions of this epidemic. Having an overview and considering food-related factors such as energy, waste, and water make the design of the supply chain more effective. In this study, a multi-objective model for a sustainable food supply chain is presented based on the prevalence of coronavirus by considering the food-energy-water-waste nexus. There are dual-channel sales including online and in-person channels, which their demand functions depend on products price in every channel, as well as the prevalence of coronavirus in high-risk or low-risk areas. Distribution centers, located in high-risk regions, require the disinfection of products to minimize coronavirus spread. Indeed, the proposed mathematical model has three objective functions that the first objective maximizes the profit of the food supply under COVID-19 conditions. The other two objectives minimize not only the environmental impact of transportation, but also the delivery time. In order to solve this multi-objective model, the epsilon constraint method, as an efficient technique, is employed. To validate the proposed model, the model is finally implemented in a two-channel supply chain in Iran. The results show that the food supply chain has a close relationship with the energy-water-waste nexus COVID-19 and can also affect customers' behavior. Moreover, the model shows when the prevalence of COVID-19 increases, people tend to buy from online shops, affecting product prices that can change by nearly 50%.

Graphical abstract

Has the COVID-19 pandemic changed household food management and food waste behavior? A natural experiment using propensity score matching

Household food management behavior changed considerably during the COVID-19 pandemic. A growing body of work has quantified the impact of lockdowns on household food waste. Yet, previous studies used a retrospective study design which undermines the accuracy of the causal effect on household food waste. This paper investigates the causal impact of the COVID-19 pandemic on household food management and food waste using a natural experiment approach. Using two large national-scale longitudinal data sets (n = 8157), this study quantifies the impact of COVID-19 on food waste and food behavior of Australian households. Propensity score matching (PSM) was carried out to address potential endogeneity issues and to select control and treatment groups for analysis. Findings reveal that Australian households reduced food waste by 9% on average in 2020 (during COVID-19) compared to the pre-pandemic (2019) level. The use of a grocery list, discount purchases, and 'just-in-case' purchases, and food refrigeration have recorded a marked increase during the pandemic compared to pre-pandemic times. The changes to food management and food discard behavior during the pandemic offer important insights for behavior change campaigns to reduce household food waste. Interventions to sustain good food planning and storage practices and involving food retailers are promising entry points in addressing household food waste. The study also highlights the considerable challenge in achieving SDG 12.3 target by 2030.

Digital food sharing and food insecurity in the COVID-19 era

Sharing food surplus via the digital sharing economy is often discussed as a promising strategy to reduce food waste and mitigate food insecurity at the same time. Yet if and how the global pandemic has affected digital food sharing are not yet well understood. Leveraging a comprehensive dataset covering over 1.8 million food exchanges facilitated by a popular peer-to-peer food sharing platform, we find that UK activity levels not only rose during the Covid-19 pandemic, but outperformed projections. A potential explanation for this growth might be the rise of food insecurity during the pandemic. Yet examining the sociodemographic characteristics of platform users, average user activity and food exchanges before and during the pandemic, we find no compelling evidence that the platform's pandemic-era growth results from a large influx of food insecure users. Instead, we poist that the growth in digital food sharing relates to lifestyle changes potentially triggered by the pandemic.

A data-driven decision support system with smart packaging in grocery store supply chains during outbreaks

The unexpected emergence of the COVID-19 pandemic has changed how grocery shopping is done. The grocery retail stores need to ensure hygiene, quality, and safety concerns in-store shopping by providing "no-touch" smart packaging solutions for agri-food products. The benefit of smart packaging is to inform consumers about the freshness level of a packaged product without having direct contact. This paper proposes a data-driven decision support system that uses smart packaging as a smart product-service system to manage the sustainable grocery store supply chain during outbreaks to prevent food waste. The proposed model dynamically updates the price of a packaged perishable product depending on freshness level while reducing food waste and the number of rejected customers and maximising profit by increasing the inventory turnover rate of grocery stores. The model was tested on a hypothetical but realistic case study of a single product. The results of this study showed that stock capacities, freshness discount rate, freshness period, and quantity discounts significantly affect the performance of a grocery store supply chain during outbreaks.

Food waste in time of COVID-19: The heterogeneous effects on consumer groups in Italy and the Netherlands

Since COVID-19 outbreak, States adopted different combinations of measures to restrain its spread that affected individual behaviors and the already fragile local and global food systems. The aim of this research is to contribute to the scientific debate around food systems sustainability through the analysis of behavioral shifts in household food waste drivers, specifically occurring during the recent global pandemic. A survey was developed based on an extended version of the Motivation-Opportunity-Ability (MOA) approach. A representative sample of 3000 respondents in Italy and in the Netherlands (1500 per country) completed this survey in May 2020, while lockdown to mitigate the first wave of COVID-19 outbreak was active in both countries. A cluster analysis based on individual food-waste- related behaviors identified four homogenous groups of consumers in the Italian sample and five in the Dutch sample. The comparative analysis of these groups led to the identification of several communalities in behavioral patterns, both within and between the two countries. Results suggest that in both countries, self-reported quantities of household food waste actually decreased, with a stronger reduction reported by Italian consumers. The MOA approach allowed to explain this perceived reduction as largely depending on the increase of opportunity to dedicate more time - to food-related activities as compared to the pre-COVID-19 period, with positive consequences on food management ability. These findings assist in drafting recommendations for tailored interventions to reduce the amount of domestic food waste and preserve positive behaviors emerged during lockdown, that could be continued in the absence of crisis.

Food Waste Treatments and the Impact of Composting on Carbon Footprint in Canada

Forty percent of the food generated in Canada is wasted, making it the most significant component of municipal solid waste. Food waste characteristics, such as high moisture and oil content, and variable composition, make it difficult to manage with conventional waste treatment methods. Part of food waste is disposed of in landfills, generating greenhouse gases and significantly increasing the carbon footprint. Various treatment methods such as composting and anaerobic digestion have been employed to treat and manage the remaining waste efficiently. This study provides an overview of the impact of composting as a food waste treatment method in Canada and paves way for the research of the usefulness of composting in addition to other food waste treatment methods such as anaerobic digestion. Average composting data for Canada was used to determine the change in the carbon footprint by the diversion of food waste using CCaLC2 software. It was determined that the overall carbon footprint of 1.38 and 1.33 mega-tons of CO2 was reduced from the composting of food waste in the years 2014 and 2016, which were approximately 18% and 20% of the total footprint of Canada municipal solid waste, respectively. The carbon footprint data collected herein were compared to the data from England, Sweden, and the USA to reveal the high effectiveness of composting in Canada.

A review of the effects of COVID-19 on food waste

The COVID-19 pandemic exposed significant vulnerabilities in systems of production and consumption. In particular, the economic and social implications of the pandemic highlighted the urgent need for more sustainable and less impactful practices of food production and consumption. Through a systematic literature review, this paper seeks to assess how the pandemic affected the phenomenon of food waste, with the aim of assessing whether the pandemic stimulated changes amongst food system actors, especially consumers. The findings indicate that consumers generally reported behavioural changes during the pandemic and claimed to have adopted sustainable practices that could contribute to reducing food waste. The results also reflect the rapid diffusion of practices such as food delivery during the pandemic, which requires further investigation in terms of its effects on the environment. Simultaneously, supply-demand shocks and disruptions were reported in the areas of production, processing, and retailing, suggesting the occurence of ripple effects. A call is made for greater resilience in the food system, through the adoption of sustainable and less impactful practices, supported by policy.

The Proof Is in the Pudding: Using a Randomized Controlled Trial to Evaluate the Long-Term Effectiveness of a Household Food Waste Reduction Intervention During the COVID-19 Pandemic

To halve per capita global food waste by 2030, policies and programs that effectively reduce household food waste generation are needed. Building upon a previous randomized controlled trial, this study evaluated the long-term effectiveness of the "Reduce Food Waste, Save Money" household food waste reduction intervention by comparing direct measurements of household food waste generated by treatment (n = 47) and control households (n = 52) over three time periods. The results indicate that there has been a long-term, sustained 30% reduction of avoidable food waste sent to landfill by treatment households following the implementation of this intervention. Additionally, this study assessed the impact of pandemic circumstances on the quantity and composition of household food waste by comparing direct measurements of food waste generated by the same households before (October 2017) and during (June 2020) the COVID-19 pandemic. During the first wave of the pandemic in Ontario, Canada, study households (n = 99) sent 2.98 kg of food waste to landfill per week, of which 54% was classified as avoidable food waste, and the remaining 46% as unavoidable food waste. During the pandemic, the generation of unavoidable food waste significantly increased by 65% (p < 0.01). There were also significant changes to the composition of wasted food, including a 78% increase in avoidable fruit and vegetables (p < 0.01), a 228% increase in avoidable other food (p < 0.01), and an 84% increase in unavoidable other food (p = 0.02).

Understanding the management of household food waste and its engineering for sustainable valorization- A state-of-the-art review

Increased urbanization and industrialization accelerated demand for energy, large-scale waste output, and negative environmental consequences. Therefore, the implementation of an effective solid-waste-management (SWM) policy for the handling of food waste is of great importance. The global food waste generation is estimated at about 1.6 gigatons/yr which attributes to an economic revenue of 750 billion USD. It can be converted into high-value enzymes, surfactants, Poly-hydroxybutyrate, biofuels, etc. However, the heterogeneous composition of food with high organic load and varying moisture content makes their transformation into value-added products difficult. This review aims to bring forth the possibilities and repercussions of food waste management. The socio-economic challenges related to SWM are comprehensively discussed particularly in terms of environmental concern. The engineering aspect in the collection, storage, and biotransformation of food waste into useful value-added products such as biofuels, advanced biomaterials, bioactive compounds, and platform chemicals are critically reviewed for efficient food waste management.

The Influence of Selected Food Safety Practices of Consumers on Food Waste Due to Its Spoilage

Food waste in households is a consequence of the accumulation of improper practices employed by consumers when dealing with food. The survey estimated the impact of practices of Polish respondents, in the context of selected food safety and hygiene issues, on throwing away food due to spoilage. The survey was conducted in 2019, in a random quota-based, nationwide sample of 1115 respondents 18 years old and older. Synthetic indicators (SI) were created to assess the knowledge and practices of Polish adult respondents concerning selected areas of food management and the frequency of throwing food away. Most food products were not thrown away at all or were thrown away occasionally. Regression analysis revealed that the frequency of throwing food away was to the greatest extent related to food spoilage (β = 0.223). Among the five areas of Polish respondents’ practices covered by the analysis, the most conducive to wasting food due to spoilage were improper proceedings with food after bringing it home (β = 0.135; p = 0.000), a failure to ensure proper food storage conditions (β = 0.066; p = 0.030), or inappropriate proceedings with uneaten meals, excluding the food plate (β = 0.066; p = 0.029). To reduce food waste in Polish households, drawing the attention of consumers to the conditions of food storage at home seems appropriate. It is also vital to convince them to use freezing of uneaten food as an effective method of extending the life of food products.

Canadian Consumers’ Dining Behaviors during the COVID-19 Pandemic: Implications for Channel Decisions in the Foodservice Industry

The past two years have been challenging for the restaurant industry in Canada and countries worldwide. This has led many casual and fine dining restaurants to adapt their business models to overcome the immediate and long-term impacts of the COVID-19 pandemic. This paper aims to understand how COVID-19 has impacted Canadian consumers’ on- and off-premise dining behaviors and how such behaviors vary among various sociodemographic groups, general knowledge of COVID-19, and telecommuting. Data were collected from a nationally representative consumer panel (n = 1091), from a survey administered online by Angus Reid. The results show that Canadian consumers increased their off-premise dining experiences during the COVID-19 pandemic, which also varied across various sociodemographic groups. There was also an increased level of telecommuting during the pandemic, of which 68% started following the pandemic. However, telecommuting was negatively correlated with off-premise dining experiences during the pandemic. Canadian consumers perceived off-premise dining during the pandemic as reasonably expensive, lesser quality, and more convenient. The findings may have important implications for casual and dining restaurants in Canada to improve channel decisions and messaging as operators prepare for a full-service post-COVID-19. They can build on the infrastructure and capability that has been established during the COVID-19 pandemic to offer sustainable services beyond the pandemic.

Impact of COVID-19 on Food and Plastic Waste Generated by Consumers in Bangkok

The crisis ignited by COVID-19 has transformed the volume and composition of waste generation and requires a dynamic response from policy makers. This study selected Bangkok as a case study to semi-quantitatively examine the impact of the COVID-19 outbreak on consumer-generated food and plastic waste by examining changes in lifestyles and consumption behaviour through a face-to-face questionnaire survey. Travel bans and diminished economic activity due to COVID-19 have led to a dramatic reduction in waste from the business sector and in the total amount of municipal waste generated. However, the results of the survey showed that both food and plastic waste generated by households in Bangkok increased during COVID-19. The shift from eating out to online food delivery services led to an increase in plastic bags, hot-and-cold food bags, plastic food containers, and food waste. Reasons for the increase in household food waste during COVID-19 varied, with respondents citing excessive amounts of food and unappetising taste, followed by exceeding the expiration date and rotting/foul odours. These reasons may be the result of the inability to predict quantity and quality when ordering online, and inadequate food planning and management by consumers. To achieve more effective food and plastic waste management, home delivery services, consumer food planning and management, and the formation of a circular economy based on localised supply chains may be considered as important intervention points.