Surplus food donation: Effectiveness, carbon footprint, and rebound effect

Surplus food redistribution can be a way to relieve co-existing food insecurity and food waste. The food waste hierarchy ranks surplus food donations for human consumption as the next best strategy, when food waste cannot be prevented. However, the effectiveness of food donation in terms of the amount consumed, or food donation as a food waste management measure have rarely been assessed. The few studies conducted to date report substantial environmental savings, but the results may be sensitive to assumptions regarding substituted food. Rebound effects are also not included, but are likely to offset environmental savings from food donation. Therefore, this study investigated the effectiveness, carbon footprint, and rebound effect of a food donation system run by a charity in Sweden, and compared the results with those of anaerobic digestion. Multiple analytical methods were used, including material flow analysis, life cycle assessment, questionnaire, and 24-hour dietary recall. In the life cycle assessment, carbon footprint of substituted products were credited to the overall results using a system expansion. In addition, direct and indirect rebound effects associated with re-spending of substitution-related monetary savings were included. The results revealed a complex but effective network aimed at salvaging as much of the redistributed food as possible, with 78% of redistributed food eaten, but there was also a substantial rebound effect, offsetting 51% of potential carbon emissions savings from food donation. Nonetheless, the net result of food donation was almost twice the climate benefit of anaerobic digestion (-0.40 vs. -0.22 kg CO2e/FU), supporting the food waste hierarchy

Ecosystem properties and principles of living systems as foundation for sustainable agriculture – Critical reviews of environmental assessment tools, key findings and questions from a course process

With increasing demands on limited resources worldwide, there is a growing interest in sustainable patterns of utilisation and production. Ecological agriculture is a response to these concerns. To assess progress and compliance, standard and comprehensive measures of resource requirements, impacts and agro-ecological health are needed. Assessment tools should also be rapid, standardized, userfriendly, meaningful to public policy and applicable to management. Fully considering these requirements confounds the development of integrated methods. Currently, there are many methodologies for monitoring performance, each with its own foundations, assumptions, goals, and outcomes, dependent upon agency agenda or academic orientation. Clearly, a concept of sustainability must address biophysical, ecological, economic, and sociocultural foundations. Assessment indicators and criteria, however, are generally limited, lacking integration, and at times in conflict with one another. A result is that certification criteria, indicators, and assessment methods are not based on a consistent, underlying conceptual framework and often lack a management focus. Ecosystem properties and principles of living systems, including self-organisation, renewal, embeddedness, emergence and commensurate response provide foundation for sustainability assessments and may be appropriate focal points for critical thinking in an evaluation of current methods and standards. A systems framework may also help facilitate a comprehensive approach and promote a context for meaningful discourse. Without holistic accounts, sustainable progress remains an illdefined concept and an elusive goal. Our intent, in the work with this report, was to use systems ecology as a pedagogic basis for learning and discussion to: - Articulate general and common characteristics of living systems. - Identify principles, properties and patterns inherent in natural ecosystems. - Use these findings as foci in a dialogue about attributes of sustainability to: a. develop a model for communicating scientific rationale. b. critically evaluate environmental assessment tools for application in land-use. c. propose appropriate criteria for a comprehensive assessment and expanded definition of ecological land use

Sustainability assessment of surplus food donation: A transfer system generating environmental, economic, and social values

Retailers' food waste, often consisting of edible food, could be reduced, while simultaneously tackling food insecurity, through surplus food donations to vulnerable groups. However, sustainability assessments of food donations covering all three sustainability perspectives are scarce, hampering decision-makers in prioritizing donation as a food waste management measure. This Swedish case study assessed the environmental, economic, and social aspects of surplus food donation and examined trade-offs between the different sustainability perspectives. Methods included life cycle assessment, net economic benefit calculation, social life cycle assessment based on food security questionnaires, and nutritional assessments. The results showed that food donation was a way to reduce food waste benefitting the environment and adding economic and social value, to vulnerable people in particular. Despite substantial rebound effects offsetting some potential environmental savings, food bag donations outcompeted anaerobic digestion as a food waste management option in terms of environmental mitigation effect. Regarding trade-offs, accrued savings causing the rebound effects generated important social value for the donation recipients, by relieving their personal finances. Private and public investment was required to fund the donation units, but positive economic value was generated through valorization of surplus food. Food bag donations also showed potential to alleviate recipients' food insecurity and to contribute positively to recipients' nutrition intake. To realize the potential of surplus food donation, policy measures should be better aligned with the waste hierarchy. Despite some trade-offs and inability to solve the underlying problems of food insecurity, food donations have great short-term potential to contribute to a more sustainable society

Sustainability Assessment of Food Redistribution Initiatives in Sweden

Food banks that redistribute surplus food from retailers and the food industry to people in need are not a new concept globally, but their connection to food waste prevention is new. As a result, new types of food redistribution units are emerging and diversifying to find new target groups and distribution methods. The aim of this study was to identify and study surplus food redistribution units in Sweden,and then to assess the impact on several sustainability indicators for selected redistribution units, in order to increase knowledge on the types of values these redistribution concepts generate. The methods used for analyzing the scenarios were Environmental Life Cycle Assessment, Life Cycle Costing and Social Life Cycle Assessment. The results showed that providing food bags to socially exposed people generated the largest reduction of greenhouse gas emissions per kg of redistributed food (−1.2 kg CO2eq./FU). Reprocessing surplus food to a high-quality end-product was attributed a high social value, due to job creation effects in the high number of working hours required per kg of redistributed food. With regard to economic impacts, all but two scenarios studied had monthly financial losses,and therefore needed other sources of financial support

Life cycle assessment of fish oil substitute produced by microalgae using food waste

Fish oil has been used in conventional aquaculture for decades, despite the known links between increasing global demand for fish and depletion of natural resources and vital ecosystems (FAO, 2020, 2019). Alternative feed ingredients, including algae oil rich in docosahexaenoic acid (DHA), has therefore been increasingly used to substitute traditional fish oil. Heterotrophic algae cultivation in bioreactors can be supported by a primary carbon feedstock recovered from food waste, a solution that could reduce environmental impacts and support the transition towards circular food systems. This study used life cycle assessment to quantify environmental impact of DHA produced by the heterotrophic algae Crypthecodinium cohnii, using short-chain carboxylic acids derived from dark fermentation of food waste. The future potential of DHA from algae was evaluated by comparing the environmental impact to that of DHA from Peruvian anchovy oil. With respect to global warming, terrestrial acidification, freshwater eutrophication and land use, algae oil inferred -52 ton CO2eq, 3.5 ton SO2eq, -94 kg Peq, 2700 m2 eq, respectively per ton DHA. In comparison, the impact per ton DHA from fish oil was -15 ton CO2eq, 3.9 ton SO2eq, -97 kg Peq and 3200 m2 eq. Furthermore, algae oil showed lower climate impact compared to canola and linseed oil. By including Ecosystem damage as indicator for ecosystem quality at endpoint level, the important aspect of biodiversity impact was accounted for. Although the method primarily accounts for indirect effects on biodiversity, DHA from algae oil showed lower Ecosystem damage compared to fish oil even when future energy development, optimized production, increased energy demand and effects on biotic resources were considered via sensitivity analyses. As the results suggest, algae oil holds a promising potential for increased sustainability within aquaculture, provided that continued development and optimization of this emerging technology is enabled through active decision-making and purposeful investments

Environmental benefits of circular food systems: The case of upcycled protein recovered using genome edited potato

Although essential in the human diet, large quantities of available protein are currently lost or under-utilized within the food system, including protein rich side streams from conventional potato starch production. By using the genome editing technique CRISPR-Cas9, conventional starch potato cultivars can be upgraded to facilitate high-value recovery of potato protein fit for human consumption. In turn, this could support the nessecary transition towards more circular food systems. The aim of this study was to assess what environmental benefits could be gained by shifting from conventional protein recovery practice to a novel approach using genome edited potato. Our results, using consequential life cycle assessment, showed that the novel protein recovery scenario provided substantial environmental savings for every ton potato starch produced, with a reduction in global warming impact, terrestrial acidification, land use and ecosystem damage of −720 kgCO2eq, −13 kgSO2eq, −760 m2a crop eq, and −1.1 × 10−5 species.yr respectively. The potential environmental benefits of using genome edited potato were maintained even when simulating reduced tuber yield, increased production inputs, and substitution of various protein sources. Although currently limited by EU legislation and technical maturity, high-value protein recovery from food side streams holds a promising potential to support sustainable production and circularity within the food system

Hydrogen peroxide contributes to the ultraviolet-B (280-315 nm) induced oxidative stress of plant leaves through multiple pathways

Solar UV-B (280-315 nm) radiation is a developmental signal in plants but may also cause oxidative stress when combined with other environmental factors. Using computer modelling and in solution experiments we show that UV-B is capable of photosensitizing hydroxyl radical production from hydrogen peroxide. We present evidence that the oxidative effect of UV-B in leaves is at least two-fold: (i) it increases cellular hydrogen peroxide concentrations, to a larger extent in pyridoxine antioxidant mutant pdx1.3-1 Arabidopsis and (ii) is capable of a partial photo-conversion of both ‘natural’ and ‘extra’ hydrogen peroxide to hydroxyl radicals. As stress conditions other than UV can increase cellular hydrogen peroxide levels, synergistic deleterious effects of various stresses may be expected already under ambient solar UV-B

Proline 411 biases the conformation of the intrinsically disordered plant UVR8 photoreceptor C27 domain altering the functional properties of the peptide

UVR8 (UV RESISTANCE LOCUS 8) is a UV-B photoreceptor responsible for initiating UV-B signalling in plants. UVR8 is a homodimer in its signalling inactive form. Upon absorption of UV radiation, the protein monomerizes into its photoactivated state. In the monomeric form, UVR8 binds the E3 ubiquitin ligase COP1 (CONSTITUTIVELY PHOTOMORPHOGENIC 1), triggering subsequent UV-B-dependent photomorphogenic development in plants. Recent in vivo experiments have shown that the UVR8 C-terminal region (aa 397–423; UVR8C27) alone is sufficient to regulate the activity of COP1. In this work, CD spectroscopy and NMR experiments showed that the UVR8C27 domain was non-structured but gained secondary structure at higher temperatures leading to increased order. Bias-exchange metadynamics simulations were also performed to evaluate the free energy landscape of UVR8C27. An inverted free energy landscape was revealed, with a disordered structure in the global energy minimum. Flanking the global energy minimum, more structured states were found at higher energies. Furthermore, stabilization of the low energy disordered state was attributed to a proline residue, P411, as evident from P411A mutant data. P411 is also a key residue in UVR8 binding to COP1. UVR8C27 is therefore structurally competent to function as a molecular switch for interaction of UVR8 with different binding partners since at higher free energies different structural conformations are being induced in this peptide. P411 has a key role for this function