Purpose This study aims at defining and quantifying strategies to reduce the environmental impact caused by public and private Danish meal service supplying vulnerable home-dwelling senior citizens. Besides informing the scientific community, the goal is to inform decision makers at municipal and private commercial kitchens about their potential role in significantly reducing the environmental impact of the meal services by conscious, deliberate, and sustainable choices at each step of the meal-selection- production-packaging-delivery-chain. Methods The Danish meal service is represented by five public and private meal producers with a combined annual production of 1.2 million main meals targeted at sustaining senior citizens living at home throughout nine municipalities. Forty-seven main meal recipes, divided into five categories, represent the typically available meals: vegetarian, fish/seafood, pork, poultry, and veal/beef. The study quantifies the environmental impact of the five meal categories by consequential life cycle assessment, using three functional units (mass, energy, and protein content) to investigate if differential impacts among the meal categories can support sustainability-improving strategies. Two impact categories, global warming and the monetized overall environmental impact, were calculated for each recipe, including all ingredients and processing. The environmental impacts of packaging, meal delivery, and food waste were estimated separately. Results and discussion The average environmental impact of main meals with veal/beef were 5–7 times higher than the average impact of all other meals, and 8–11 times higher impact than the impact of the average vegetarian meal. The ranges reflect differences in the chosen functional unit and impact category. Differences among the non-beef meal categories were smaller, with vegetarian and fish/seafood meals having the lowest impact. The average global warming impact of the average main meals was 3.70 kg CO -eq and the overall monetized impact 0.62 €. Impact of waste was 0.03–0.18 kg CO -eq and 0.007–0.023 € per meal 2 2 in kitchens, and 0.031–0.329 kg CO -eq and 0.006–0.041 € for consumers. The environmental impact of packaging added 0.07 kg CO -eq and 0.006 €, and meal delivery 0.026–0.435 kg CO -eq and 0.005–0.09 € per meal. 2 2 Conclusions The most important strategy for reducing the environmental impact of Danish meal service is to reduce the number of meals containing veal/beef. Vegetarian meals were rarely more sustainable than fish/seafood. Packaging, food waste, and delivery of meals played minor roles in the overall sustainability of Danish meal service, and the most efficient strategy to reduce the environmental impact of these activities would be to deliver meals weekly rather daily. . . . . Keywords Consequential life cycle assessment Dependent senior citizens Global warming potential (GWP ) Meal service Monetized environmental impact Municipal kitchens Responsible editor: Niels Jungbluth. Electronic supplementary material The online version of this article (https://doi.org/10.1007/s11367-018-1487-z) contains supplementary material, which is available to authorized users. * Henrik Saxe Department of Food and Resource Economics, Section of HenrikSaxe@gmail.com Consumption, Bioethics and Governance, Faculty of Science, University of Copenhagen, Frederiksberg C, Denmark Department of Food Science, Section for Food Design and Consumer Behaviour, Faculty of Science, University of Copenhagen, Frederiksberg C, Denmark Int J Life Cycle Assess 1 Introduction are provided in different catering situations such as schools, hospitals, and elderly care. Public meals prepared for senior The aging populations are one of the most important demo- citizens in care centers and especially through home catering graphic events of our time. Initially experienced by the more in the so-called meals on wheels are expected to grow in most developed countries, the trend has recently become apparent parts of the world due to the increasing segment of the old and in much of the developing world as well. Many countries are very old citizens. With predictions on how such food catering already in the midst of population aging, although at varying in the future will develop, it is important to assess the overall levels and time frames. In the EU, the share of people over 60 environmental impact of commercial and municipal catering is presently around 15%, but that figure is expected to reach kitchens for senior citizens. This could lead to strategies for 30% by 2050 (UN 2015; Giacalone et al. 2016). rational and optimal use of resources for sustainable develop- Consequently, the demand for health care, welfare, and the ment in public procurement. economic impact of aging populations will increase in the Although the current focus within the large municipal or coming years. In addition, the number of home-dwelling and private kitchens catering for senior citizens is on the health senior citizens in care centers, who are dependent on different and well-being of its customers, both the overall environmen- forms of personal care, will increase. One of the most impor- tal impact and health aspects have significant socioeconomic tant daily needs for such dependent senior citizens will be an implications (Jensen et al. 2015; Tilman and Clark 2014; adequate food provision. In several European countries, this is Hällström et al. 2017). In the present study, we evaluate the currently arranged by centralized catering of meals to individ- environmental impact and its monetized value of a wide range uals at home or to care centers on a daily or less frequent basis. of meal choices and delivery strategies in the meal catering for Low BMI and weight loss are risk factors for mortality in dependent senior citizens in Denmark produced at five differ- older people (Dey et al. 2001). Declines in skeletal muscle ent central kitchens. To support the simple selection of sus- mass and strength are major contributors to increased mortal- tainable meals and meal components, the meals were divided ity, morbidity and reduced quality of life in senior citizens into five easily distinguishable categories expected to cause (Nowson and O’Connell 2015). They need to have regular different environmental impacts: (1) vegetarian, (2) fish/sea- meals with sufficient energy (MJ) and protein nutrition, and food, (3) pork, (4) poultry, and (5) beef. to exercise in order to retain muscular strength. While an im- The study aimed to evaluate the environmentally most portant focus in food catering for senior citizens is thus on impacting steps across the whole meal-production-delivery- healthy nutrition, little is known on the environmental impact chain. Furthermore to suggest strategies on how to improve of the catering services from choice of raw materials, recipes, environmental sustainability of public meal service based on processing, packaging, meal delivery, and waste. quantification and comparison of the environmental impacts of the five meal categories depending on the choice of relevant It is well established that dietary composition (besides food waste) at the population level is one of the main drivers of functional units (FU: mass, energy, or protein content) and global environmental impacts and has thus been placed at the important impact categories (global warming potential or the heart of the 2030 Agenda for Sustainable Development (Sala combined monetized impacts of 16 impact categories). The et al. 2017). Production of foods and beverages is responsible study outcome is aimed to contribute to rationalize the public for about half of the environmental impact caused by people’s debate and inform decision makers at municipal and private private activities, which in turn is responsible for about half of commercial kitchens about their potential role in reducing the overall environmental impact caused by our society; the environmental impacts of the current meals on wheels catering remaining half is caused by industry. Therefore, the selection for dependent senior citizens in Denmark and countries with a of environmental friendly meals can reduce the environmental similar social service. impact of foods and beverages in the order of 35–65% (Saxe 2014). While producers at all levels have been doing their utmost to reduce food waste, the consumer still has a role to 2 Materials and methods play in the overall 30% food waste from soil to table to leftovers. 2.1 Meal service providers, recipes, and nutrient There are many examples of the environmental impact of content food and food consumption in general (Notarnicola et al. 2017; Saner et al. 2016;Saxe 2014;Saxeetal. 2017; Five Danish public and private large-scale meal service pro- Vermeulen et al. 2012). However, only few recent studies viders filled in a detailed questionnaire in advance of our visit have addressed the environmental impact of public food ser- to each kitchen in order to obtain Life Cycle Inventory (LCI) vices (Caputo et al. 2017; Jungbluth et al. 2016). Public meals data on all ingredients for all recipes, associated energy Int J Life Cycle Assess consumption for cooking/preparation and storage, packaging, Denmark: Albertslund, Allerød, Hillerød, Frederikssund, and meal delivery, and waste. To represent the meal service pro- Halsnæs. viders’ overall production, we selected 45 of their most pop- ular recipes (largest production volume) within five pre- 2.2 Assessment of environmental responses selected categories, based on the main protein ingredient: and monetized effect beef, pork, chicken, fish/seafood, and vegetarian. To illustrate the fact that some more rarely served meals may differ con- The environmental impact of the 47 recipes, i.e., the impact of siderably in environmental impact, we included two outliers in ingredients (from the global market), cooking and storage (en- our analyses. There were nine representative recipes per cate- ergy consumption), packaging, delivery, and waste (except gory and a single outlier for both seafood and poultry (recipes waste treatment) was calculated by consequential life cycle as- are detailed in the Electronic Supplementary Material no. 1). sessment (cLCA) (Fig. 1). CLCAs seek to identify the environ- Table 1 summarizes the nutrient data further specified in the mental consequences of a decision or a proposed change in a Electronic Supplementary Material no. 2. system under study (oriented towards the future), which means According to an ANOVA test, the protein, energy, and fat that market and economic implications of a decision are taken content do not differ significantly between the five meal cat- into account (Earles and Halog 2011). More specifically, we egories. The meal categories differ significantly in their acces- selected data based on consequential modelling because: sible carbohydrate and dietary fiber content. The explanation for this could be that vegetarian meals contain much more (1) The goal of our study was to systematically compare the dietary fiber than non-vegetarian meals, while non- sustainability of meal categories produced for the senior vegetarian meals contain much less accessible carbohydrate. citizens defined by their main protein ingredient. The fur- The five kitchens annually delivered over 1¼ million main ther aim was to inform politicians as well as decision meals to home-dwelling senior citizens in nine Danish munic- makers (LCA 2.-0 Consultants 2015;Weidema 2017)at ipalities. These are the data analyzed in this study, though the municipal and private commercial kitchens of their poten- results also applies to catering at care centers except for the tial role in reducing the environmental impact of the meal delivery impact. Table 2 shows that the same five kitchens services by conscious, deliberate, and sustainable choices also delivered ¾ million main meals to care centers in the at each step of the meal-selection-production-delivery- same municipalities. An annual production of approximately chain, the choice of protein ingredients likely being the 2 million main meals. most important. Det Gode Køkken delivered meals within Holstebro munic- (2) It is important to consider market information in the LCI ipality, Køkkenområdet delivered within Hjørring municipal- data of agricultural products (Zamagni 2012) since sev- ity, Dit Lokale Køkken delivered within Herning municipality, eral of these originate from multi-functional sources. Mad og Måltider delivered within Aabenraa municipality, all System boundary expansion in cLCA is more suitable in Western Denmark. Mad til Hver Dag delivered meals to than aLCA as this study involves meal ingredients ob- dependent senior citizens within five municipalities in Eastern tained on the global market. Table 1 Energy and nutrient Meal category Per 100 g KJ Total protein Accessible Dietary fiber Total fat content carbohydrate Vegetarian n = 9 Average 671 7.8 16.3 2.7 6.7 SD 219 3.9 3.7 1.5 3.9 Fish/seafood (n = 9) Average 585 6.9 9.0 1.1 8.3 SD 314 1.6 5.2 0.3 6.4 Pork (n = 9) Average 602 6.3 10.0 1.2 8.5 SD 125 1.5 2.1 0.2 2.8 Poultry (n = 9) Average 472 8.2 8.7 1.4 4.7 SD 126 1.8 3.0 0.5 2.4 Beef (n = 9) Average 555 7.6 10.6 1.4 6.4 SD 119 3.1 2.4 0.5 1.5 One-way ANOVA (P value) 0.2994 0.7019 0.0006 0.0005 0.2131 Int J Life Cycle Assess Table 2 Number of meals Producer name (kitchen location) Delivered to private homes Delivered to care centers annually catered to dependent senior citizens at home and in care Mad og Måltider (Aabenraa) 145,599 121,807 centers by the five large-scale production kitchens Dit Lokale Køkken (Herning) 72,103 154,705 Mad til Hver Dag (Hillerød) 660,000 126,000 Køkkenområdet (Hjørring) 228,402 197,465 Det Gode Køkken (Holstebro) 130,000 168,000 Total 1,236,104 767,977 (3) We included the global warming potential (GWP, CO - with pork, chicken, fish, or vegetarian for protein. This eq measured over 100 years; IPCC 2013) associated with would result in small reduction in Danish pork export land use changes, since these are of particular importance (Denmark at present exports 90% of its production), for animal-based protein sources. LUC values were and an increased production of chicken, fish, and vege- adopted from Audsley et al. (2009). table protein, all of which can be upscaled locally. (4) The background data for the environmental assessment was obtained and constructed from the Ecoinvent data- base version 3.3 using consequential data only, and with The scope of the present study included the response of 16 assumptions and affected processes/technologies being environmental impact categories associated with all activities, pre-defined by the associated investigators (Ecoinvent energy, and resource consumption in the complete production- 2016) using the Simapro 8.3 software. The delivery-chain depicted in Fig. 1. Stepwise2006 version 1.05 method was applied to facil- The environmental impact of the five food services deliv- itate monetizing (Weidema 2009; Pizzol et al. 2015). We ering the 47 different meals was calculated from soil to the present characterized and weighed results. The Stepwise doorsteps of dependent senior citizens. Transport impact was method combines methods from Impact 2002+ version calculated according to Saxe (2014), depending on the origin 2.1 and EDIP 2003 with small modifications. Stepwise of meal ingredients in a global marked. Delivery from normalizes data by monetization expressed in Euro, thus kitchens to private homes was based on type of vehicles and calculating the potential socioeconomic cost of environ- average distances. Based on a separate questionnaire filled out mental externalities. The selection of meals prepared for by dependent senior citizens, we obtained data on waste in the the senior citizens is partly a nutritional and partly a private homes (Section 2.5). Waste treatment and energy for political issue and we recognize that decision makers cooking, heat, and power associated with the private homes understand Bmoney^ better than Benvironmental was outside the scope of this study, as these were estimated to impacts.^ Environmental friendly decisions on main be insignificant and similar for all meal types. The impacts meal composition for the senior citizens could have included in the Stepwise 1.05 method are human carcinogenic large-scale consequences. and non-carcinogenic toxicity [chloroethene-equivalent (eq)], (5) In April 2016, the Danish Council on Ethics called on the respiratory inorganics (particulate matter with a diameter of ≤ Danish government to regulate the consumption of 2.5 mm), ionizing radiation (Bq, the SI-derived unit of radio- Bclimate damaging foods^ by placing taxes on those activity, C -eq), ozone layer depletion (chlorofluorocarbon products with the highest associated emissions, i.e., 11), aquatic and terrestrial ecotoxicity (chloroethylene beef. Our study was inspired by this initiative, which triethylene glycol-eq), nature occupation (agricultural land), could have large-scale consequences far beyond the global warming (CO -eq), acidification (area unprotected eco- Danish borders. Since we base our data on Ecoinvent, systems), aquatic (NO -eq) and terrestrial (area unprotected we accept the implicit marked choice as the current state- ecosystems) eutrophication, respiratory organics (person ∙ −1 −1 2 of-the-art. As half of the Danish beef supply originates ppm ∙ h ), photochemical ozone effects on vegetation (m −1 −1 from worn-out Danish dairy cows and most of the other ∙ ppm ∙ h ), nonrenewable energy (MJ primary), and min- half from import, an excess of beef, if the number of meal eral extraction (MJ extra). However, for clarity, only data for service meals with beef are reduced, would be reduced or the three most important impact categories in monetized terms channeled otherwise, e.g., export and/or a reduction in (respiratory inorganics, nature occupation, and global beef import. There is currently no export of Danish dairy- warming) were presented separately in this study, along with cow meat. Beef meals would be substituted with meals the sum of the 13 other monetized impacts (Figs. 2 and 3). Though there will always be uncertainties associated with 1 monetization of environmental impacts, these are less impor- https://www.fcrn.org.uk/research-library/danish-ethics-council-report- tant in this study where the focus is on the relative differences describes-beef-climate-damaging-food-and-calls-beef Int J Life Cycle Assess Fig. 1 General flow diagram of Waste, % Primary producon: Meal the meal-delivery-chain from soil food/feed plants Kitchen: sto- ingredients Energy for cooking, to the senior citizens Waste rage, cooking Global market heat and power treatment & packaging Animal husbandry: Food beef, pork, chicken, ﬁsh processing transport Delivery Waste, % Senior cizens living at home between meal categories (beef, pork, chicken, fish, vegetarian) deliver meals from the kitchens to its customers driving the rather than on absolute values. All environmental impacts shortest possible overall route. were calculated according to the ISO standard 14040 (2006). The functional units (i.e., references) were mass, energy con- 2.5 Waste tent (MJ), or protein content in manufactured meals. The en- ergy and protein contents of the ingredients were taken from Waste at the kitchen level was estimated in the questionnaires the Danish FRIDA food database (2016). Energy and protein to the meal service providers as normal production waste, e.g., content as well as total carbohydrate, dietary fiber, and total fat bones and fat from meat, bones and shells from fish/seafood, in 100 g of each meal are given in Table 1 and further detailed and peel and kernels from vegetables and fruits, and as other in Electronic Supplementary Material no. 2 together with de- waste, e.g., meals lost on the floor, or not received because tails on impact assessments of each meal. customers were not at home. Waste at the consumer level was estimated from 291 filled 2.3 Cost of ingredients in questionnaires from senior citizens enrolled in meal catering service. Surveys were collected from central Based on recipes for the 47 main meals, combined with food Copenhagen (n = 89) and northern Jutland (n = 202). Three service prices for the ingredients, the ingredient costs per serv- questions focused on waste from delivered meals. The first ing for all main meals were calculated excluding VAT. Price question (Bhow often do you through away leftovers from data were for the period 2013–2014, supplied from one of the the food delivered?^) was rated on a 5-point non-dichotomous major Danish suppliers of groceries for food service operators. ordinal scale: 1 = never, 2 = a few times a year, 3 = a few times For ingredients, where more than one variety was available a month, 4 = a few times a week, 5 = daily. For quantification, from food service suppliers, the variety with the lowest price the answers were translated as 0, 2, 24, 104, and 264 times a per kg was selected for the price calculation. This implies that year. The second question (Bplease indicate how much and the price estimates represent the lowest possible ingredient which type of the delivered food you throw out on average^) cost for the respective meals. If further requirements to the was rated on a 5-point interval scale with anchored descriptors ingredients are stated (e.g., that they should be organic, should (1 = 0–19%, 2 = 20–39%, 3 = 40–59%, 4 = 60–79%, 5 = 80– be domestically produced, should be semi-processed, etc.), the 100%). For quantification, the answers were translated as unit prices will tend to be higher. 10%, 30%, 50%, 70 and 90%. The third question was open- The cost data for the 47 main meals include the cost of ended: BIf you throw out delivered food, please write what it is ingredients and of cooking and storage, but not full informa- you usually throw out (meat, vegetables, potatoes...)?^ tion about other energy use, personnel hours, depreciation and maintenance of kitchen facilities, waste management, etc. Data from Danish municipal kitchens for provision of meals 3 Results to the senior citizens suggest that ingredients on average con- stitute 30–40% of the total cost of meal service. This might 3.1 Global warming impact suggest that the capacity costs would constitute around 2.0– 2.5 € per meal and delivery 0.5–1.0 € per meal—a total of The global warming impact (GWP ) caused by the primary around 3 € per meal—which should be added to the cost production of ingredients and preparation in the central figures in Table 3, although there is of course some variation kitchens of the 47 main meal recipes relative to three function- in the time and energy requirements across meals. al units, i.e., mass, energy and protein content are given for each meal in the Electronic Supplementary Material no. 2. 2.4 Packaging and delivery Figure 2 summarizes the results, showing that main courses with beef have by far the highest impact with any of the three The meals were delivered on plastic trays for food with an functional units. The choice of functional unit (FU) depends average weight of 23 g covered with 1 g of plastic film. on the purpose of the study. The average environmental im- Small diesel vans, e.g., Fiat Ducato or Iveco were used to pact of main meals with beef had a 6.6–6.8 times higher Int J Life Cycle Assess Fig. 2 Global warming impact of 47 main meals divided into five meal categories given in Kg CO -eq per 100 g (top figure), Kg CO -eq per MJ 2 2 (middle figure), and Kg CO -eq per Kg protein in the main meals (bottom figure). The vertical lines above the columns indicate the standard deviation of the means. The numbers inside each composite bar refer to the average impact of each of the five meal categories relative to the average impact of main meals with beef. The arrows in the middle figure indicate that this poultry outlier (roast duck with potatoes and red cabbage) is outside the ordinate scale. The letters in parenthesis after meal category names on the abscissa axis indicate meal categories with similar GWP impact, i.e., categories that are not significantly different (t test, P < 0.05). As an example, fish/seafood and pork are not significantly different as indicated by Bb^. Bd^ on the other hand indicates the impact of beef meals differ significantly from all other meal categories impact (depending on the FU) than the average impact of the other four meal categories, and on average a 9.1–11.1 times higher impact than the average vegetarian meal. Differences among the non-beef meals were smaller. Statistical analyses show that the global warming impact of vegetarian and fish/seafood meals is not significantly different with any of the functional units. Similarly, fish/seafood and pork meals do not show a significantly different impact with any of the functional units, and with protein as the FU, even poultry meals share impact class with fish/seafood and pork. Outliers like the examples given for fish/seafood (grilled lob- ster with red bell peppers) and for poultry (roast duck with potatoes and red cabbage) are not included when comparing average impact values of meal categories. However, such out- lier meals are only on rare occasions served to the meal service recipients in this study. 3.2 Monetized overall environmental impact Environmental impact caused by the production and prepara- tion of the 47 main meal recipes in terms of the monetized overall environmental impact (€) relative to the three function- al units mass, energy and protein content are given in the Electronic Supplementary Material no. 2. The monetized overall environmental impact is the sum of the monetized impacts of the global warming, nature occupation, respiratory inorganics, and the sum of the remaining 13 impact categories all specified in Section 2.2. Figure 3 summarizes the results, once again demonstrating that main courses with beef have by far the highest impact using any of the three functional units. The average environ- mental impact of main meals with beef had a 4.9–5.1 times higher (depending on the FU) impact than the average of the four other meal categories, and on average a 7.7–8.3 times higher impact than the average vegetarian meal. Differences among the non-beef meals were smaller. Statistical analyses show that the global warming impact of vegetarian and fish/seafood meals are only significantly dif- ferent with energy content as the FU, where vegetarian meals have about 2/3 the environmental impact of fish/seafood and Int J Life Cycle Assess Fig. 3 Monetized environmental impact of 47 main meals divided into five meal categories (using meal category colors at the center of each column as in Fig. 2) given in Euros per 100 g (top figure), Euros per MJ (middle figure), and euros per Kg protein in the main meals (bottom figure). The vertical lines above the columns indicate the standard deviation of the means. The numbers above each composite bar refer to the average impact of each of the five meal categories relative to the average impact of main meals with beef. The colors at both edges of each column indicate the contribution to the impact by global warming, nature occupation, respiratory inorganics, and the sum of 13 other impacts, respectively. Arrows indicate that poultry outliers are outside the ordinate scale. The letters in parenthesis after meal category names on the abscissa axis indicate meal categories with similar GWP impact, i.e., categories that are not significantly different (t test, P <0.05). As an example, fish/seafood and pork are not significantly different as indicated by Bb^. Bd^ on the other hand indicates the impact of beef meals differ significantly from all other meal categories pork meals. With protein content as the FU, vegetarian meals have 60% of the impact of pork and 56% of poultry meals. Fish/seafood and pork meals do not have a significantly dif- ferent impact with any of the FUs, and with protein as the FU even poultry meals share impact class with fish/seafood and pork. Both edges of each column in Fig. 3 illustrate how the monetized environmental impact is made up (nearly indepen- dent of the FU) of a 48–49% contribution by global warming, 25–26% by nature occupation, 18% by respiratory inorganics and 8% by the sum of the 13 other impact categories (Section 2.2). However, these ratios vary between individual meals in all meal categories (data not shown). Monetized global warming impacts are dominating applying all FUs and for all meal types, except for fish/seafood where respiratory inor- ganics are of similar importance as global warming. Catching fish implicates very little nature occupation, and mainly fuel for fishing boats and power for freezing the catch. With energy content as the FU, poultry has nearly twice the environmental impact of both fish/seafood and pork, while with protein as the FU, the environmental impact of these three meal categories does not differ significantly. 3.3 Average meal Based on the production data from the five central kitchens, the average (de facto) main meal served to the senior citizens is composed of 1% vegetarian meals, 10% fish/seafood, 59% pork, 10% poultry and 20% beef meals. The global warming Table 3 Average ingredient cost of a meal in each of the five categories Meal category Vegetarian Fish/seafood Pork Poultry Beef a,b c,d c Average price 1.01 € 1.58 € 0.92 1.70 € 1.32 a b,d (N =9) € € The letters a, b, c, and d indicate that the average price of meal cate- gories with the same letter does not differ significantly from each other (t test, P <0.05) Int J Life Cycle Assess impact of the composition average meal (480 g) is calculated included at the production level of the flow, as it has been as 2.21 kg CO -eq and the overall monetized impact as 0.37 € produced and delivered. Nevertheless, the senior citizens will per meal. have to compensate for the lost intake caused by waste (leftovers) by eating more of other foods. This waste is there- 3.4 Impact of waste fore included as a small indirect impact in Fig. 4 to illustrate its relatively small impact. The five kitchens reported food waste during and after pro- duction of up to 1–5% for meat and fish, up to 1–10% for vegetables and fruit, and up to 1–2% for other ingredients. 3.5 Packaging and delivery Based on this, the overall food waste at the kitchen level For three-compartment plastic trays (23 g) and 1 g plastic film was assumed to be in the range 0.5–5% for the five kitchens. The impact of waste per main meal at the kitchen level was for cover, the environmental impact associated with packag- ing added a global warming impact of 0.07 kg CO -eq and a 0.03–0.18 kg CO -eq and 0.007–0.023 € depending on the 2 2 amount and type of wasted product. monetized overall environmental impact of 0.006 € per meal. The annual waste of main meal components at the depen- This is insignificant in relation to the overall impact of meal dent senior citizen level was estimated based on the 291 ques- service. All comparisons with, e.g., recyclable trays are there- tionnaire respondents having 260 meals per year as 300 kg fore irrelevant. potatoes, 120 kg gravy, 550 kg vegetables and 400 kg unspec- The delivery vans typically travelled about 1 km (a range of ified meat and 30 kg fish. The GWP of this was 8000 kg CO - 0.92–1.56 km) for delivery to each customer. Each delivery eq, and the monetized overall environmental impact was consisted of a single, and up to seven main meals, and in 1250 €. The typical meal service would deliver five main addition one or several dessert. The environmental impact of meal delivery by medium size vans ranged from 0.026 kg meals a week for 52 weeks a year, or 260 meals. 96,928 meals were delivered to the 291 senior citizens respondents to the CO -eq and 0.005 € per meal, and up to 0.435 kg CO -eq 2 2 and 0.09 € per meal depending on the average distance be- questionnaire described in Section 2.5. These have an estimat- ed impact of 214,000 kg CO -eq and 36,000 €. The impact of tween customers (0.92–1.56 km) and the frequency of meal waste per main meal at the individual level was 0.031– delivery (1–7 times per week). Based on these data, we calcu- 0.329 kg CO -eq and 0.006–0.041 € depending on the type lated a minimum and a maximum impact of meal delivery of meal. The direct impact of this waste has already been (Fig. 4). Fig. 4 The total global warming impact (three left columns) and overall monetized environmental impact (three right columns) of Danish meal service for average vegetarian meals (columns with a green vertical line, n = 9), de facto delivered meals (bar no. 2 and no. 5 with a yellow vertical line, n = 45), and average meals with beef (red vertical line, n = 9). The total impact is made up of contributions from meal production, packaging, waste, and delivery of the meals from the kitchens to the consumers. The percentages above each column signify the share of packaging, waste, and delivery Int J Life Cycle Assess 3.6 Cost of ingredients for each meal categories (Section 3.2). The most effective and often the only available strategy to reduce the environmental impact of the The cost of ingredients for each meal can be found in the Danish meal service is to reduce the delivered number of beef Electronic Supplementary Material no. 2, and average prices main meals. This reduction can come about by the kitchens of the five meal categories in Table 3. The average price of producing fewer meals of this type, and/or by encouraging the ingredients for main meals does not differ significantly (t test, older person to choose fewer beef meals. If the share of beef P > 0.05) between vegetarian and pork meals, between vege- meals delivered by the meal service came down from the tarian and beef, between fish/seafood and poultry meals, and present 20 to 10%, the global warming impact (kg CO -eq) between fish/seafood and beef meals. On average, pork and and the monetized overall environmental impact (€) of the vegetarian meals are cheaper than meals with fish/seafood and meal production would be reduced, depending on the FU by poultry. Ingredients only account for 20–40% of total costs of 25–26% and 19–20% respectively. a main meal, and there may be some room for modifying recipes regarding ingredients, without altering total costs dra- 4.1.2 Second strategy: choose the less impacting beef matically. For an estimate of the overall cost of meals, the capacity and delivery costs should be added to the ingredient In view of the relatively large variability of the environmental cost in Table 3. impact of beef meals (larger than the other meal categories; Figs. 2 and 3, and the Electronic Supplementary Material no. 3.7 The impact components of Danish meal service 2). To be effective, this strategy implies a need to calculate the impact of all beef meals produced by each kitchen. To reduce the total impact of a meal management system, it is necessary to look at all links in the chain (Fig. 1)(Jungbluthet 4.1.3 Third strategy: beef-free Monday al. 2016). Figure 4 gives an overview of the total impact of Danish meal service with the two impact categories used in Meatless Monday is an international non-profit initiative this study, and in this case using mass as the common FU for founded in 2003 that encourages people not to eat meat on all materials and activities. Average meals (bars with a yellow Mondays to improve their health (following the USDA nutri- vertical line) signify the de facto delivered meals, i.e., 1% tional guidelines) and the global sustainability. In our study, vegetarian meals, 10% fish/seafood, 59% pork, 10% poultry we found no effective meal choice strategies to reduce the and 20% beef meals. A de facto meal delivered to an average- environmental impact among non-beef meals. A substitution dependent senior citizen living at home is associated with an with poultry and pork meals with fish or vegetarian meals annual environmental impact of 1033 kg CO -eq and a mon- reduce the impact very little. But on the condition that one etized overall impact of 1415 €, i.e., 17 and 19% respectively beef-free day a week does not result in having more beef than of the overall impact. If the delivery included vegetarian meals usual the rest of the week, this is a third tangible strategy to only (bars with a green vertical line), the relative impact of improve the sustainability of meal service, though it may be packaging, waste and delivery would be large (40%, 39%), seen as a variation of the first strategy (Section 4.1.1)with while in case the delivery included only beef meals (bars with significant reduction of environmental impact. a red vertical line), the relative impact of packaging, waste and Serving all costumers a fish/seafood meal 1 day a week delivery would be small (10%, 12%). rather than the present mix of all five main meal categories would reduce both the global warming impact and the mone- tized overall environmental impact of the meal production by 4 Discussion 8% independent of the FU. One vegetarian day per week instead of status quo would reduce both the global warming 4.1 Seven strategies to improve the sustainability impact and the monetized overall environmental impact of of Danish meal service meal production by 9% independent on the FU. A beef-free Monday thus serves nearly as well as a meat-free Monday in In this section, we discuss which strategy is most important on protecting global sustainability. the pathtoimproving thesustainability ofmealservice. Vegetarian meals may be less preferred for the current gen- eration of senior citizens, especially in rural areas (Johansen et 4.1.1 First strategy: cut down on beef meals al., in preparation). In order to create acceptance for more vegetarian and fish/seafood meals, the central kitchens will Twenty percent of the delivered meals in this study contained have to focus on innovation, meal palatability and customer beef. Beef meals have a seven times higher impact on global satisfaction. Meals based on vegetable protein can be more warming (Section 3.1) and a five times higher monetized over- satiating than meals based on animal protein (Kristensen et al. 2016). Even when met with satiating and palatable new all environmental impact than the average of the other meal Int J Life Cycle Assess meals, the older people may not appreciate or even notice the impact of meal service by 11% and the monetized overall taste, as they with their reduced sense of taste are more likely environmental impact by 14%. to choose their meals based on habits than on palatability. An additional impact is food waste at the consumers (Fig. 4). This potentially makes up 2% of the overall impacts for the de facto delivered meals (3% if all meals were beef 4.1.4 Forth strategy: calculate impact of all meals meals). This potential impact reduction if this waste could be prevented is small and possibly be non-negotiable. Food A forth strategy to increase the sustainability of meal services wasted at the homes of the senior citizens is typically com- would be to calculate the sustainability of all meals produced pensated by additional intake of snack meals to satisfy their by a given meal service, and either modify the most impacting energy needs. Similar to Cerutti et al. (2018), we found the meals in all categories, or offer them less frequently. In that impact of packaging to be negligible. way, the older people could eat most meals in all categories that they know and are used to eating. However, selection of 4.1.7 Seventh strategy: restrict outliers the most sustainable recipes among all meal categories is a complex task outside the scope of this study. Finally, it is important to avoid, or only enjoy a few times a year, certain meals with extremely high environmental impact, 4.1.5 Fifth strategy: beef tax such as the outliers exemplified in Figs. 2 and 3. As a strategy to reduce the environmental impact of food 4.2 Large number of meals consumption, the Danish Council of Ethics suggested raising the beef prices by taxation (Lykkeskov and Gjerris 2017). If Due to the very large number of meals produced and delivered this were to come true, financial reasons would force Danish by the meal catering companies, a focused selection of meal meal services to decrease the number of beef meals they offer. supply by the management would improve the overall envi- That would be a fifth strategy to reduce the impact of meal ronmental sustainability of the food sector. The five kitchens service, and the civil societies’ overall environmental impact in this study annually produce and deliver more than 1.2 mil- caused by food. Such taxation with require a larger analysis on lion main meals (Table 2) to dependent senior citizens living at beef consumption for the whole population in order to con- home with an average impact of delivered meals of 3.7 kg vince policy makers on the environmental impact of such CO -eq/meal (Fig. 4), resulting in a total annual impact of governmental intervention. 4580 t CO -eq. Applying the first strategy to reduce the global warming impact of meal service by 25%, the five meal pro- 4.1.6 Sixth strategy: weekly meal deliveries viders would save 1140 t CO -eq per year. Such relatively easy implementable measure equals the annual emission by The meal service business involved in this study have an in- over five hundred passenger cars (Euro 5 emission standard). terest in knowing how much they can improve their overall sustainability by focusing on packaging, food waste or deliv- 4.3 Choice of functional unit and impact category ery strategies. As shown in Fig. 4, packaging, waste and de- livery make up a little less than 20% of the overall impact of Which functional unit and which impact category is the best to the meal service with the de facto combination of delivered point the kitchens towards meals with the lowest environmen- meals and with both impact categories. If more sustainable tal impact? The answer to the first question depends on the meals are delivered (i.e., all vegetarian), the packaging, waste purpose of the main meals, whether they are meant to improve and delivery would make up a larger share (39–40%), and the energy or protein content of the daily food intake of the old with less sustainable meals (e.g., all beef), a smaller share adults, or in this study both. There is increasing focus on the (10–12%) of the overall sustainability (Fig. 4). Reducing the choice of FU when LCAs are used to compare foods (Smetana impact caused by packaging, waste and delivery could be a et al. 2015; Salou et al. 2017). Recently, Sonesson et al. (2017) sixth strategy for improving meal service sustainability. pointed out that protein quality might be an even better FU However, these activities are often non-negotiable. that protein quantity. The most common FU in LCA studies, The largest impact is caused by the delivery vans, if, and mass (kg), was included in this study to be able to calculate the only if the meals are delivered daily, with low-mileage vans others, but it is meaningless in selecting the most sustainable and long average delivery distances (Bdelivery max^ in main meals, with the purpose of delivering both energy and Fig. 4) rather than bundled with all meals for a week’ssupply, proteins to the senior citizens. energy efficient vans and best-possible routing (Bdelivery The GWP is the dominant environmental impact of main minimum^). For the de facto delivery of meals, converting meal production, but except for beef meals, it makes up a little daily delivery to weekly delivery reduces the global warming less than half of the average monetized overall environmental Int J Life Cycle Assess impact of all meals (Fig. 2). Therefore, the answer to the and monetized health impact has been shown to be more im- second question is that the sum of the monetized impacts of portant than the monetized environmental impact for the New all 16 impact categories is the best environmental indicator, Nordic Diet (Saxe, 2014;Jensen et al., 2015). since it covers the overall environmental impact better than The most effective strategies to reduce the environmental any single category, even the GWP. impact of the Danish meal service all include less beef. While the strategies to improve the sustainability of the Lowering beef consumption may have positive health benefits Danish meal service are relatively independent of the applied for the senior citizens (Aune et al. 2017; Wolk 2016). The task functional unit, Figs. 2 and 3 demonstrates how the choice of of increasing sustainability of the meal service by altered diets FU affect the numbers for absolute environmental impacts and is an important challenge for the meals on wheels caterers as the ratio of impact of any given meal category to another. well as for meal service in nursing homes. Poultry-based meals show the largest variation caused by the choice of FU. The impact of poultry varies more relative to beef than the other meal categories. 5 Conclusions 4.4 The price aspect The average environmental impact of main meals with beef has a 5–7 times higher environmental impact than the average Based on the present selection of recipes, substituting main impact of the other four meal categories, and an 8–11 times meals with beef with the more fish/seafood and vegetarian higher impact than the average vegetarian meal. The variation meals will not significantly benefit the ingredient cost (Table in impact depends on the chosen functional unit and impact 3). More pork would lower the cost, while more poultry would category. increase the cost. The total cost of any meal include the ca- The most important strategy for reducing the environmen- pacity cost and delivery costs, which were estimated to be tal impact of Danish meal service is to either reduce the num- around 3 € per meal. When these capacity and delivery costs ber of meals with beef, and/or limit all meals to the most are included, the relative difference in cost of producing dif- sustainable of their kind. The strategy of having a weekly ferent meal categories is reduced. If ingredient prices is an fish/seafood or vegetarian day only improved the overall sus- issue, we recommend looking at individual recipes rather than tainability when it reduced the number of meals with beef. considering meal categories. Vegetarian meals are only a little more sustainable than fish/ In view of the environmental impact of disposable plastic seafood. Packaging, food waste and delivery of meals play a trays (Section 3.5) for meal service delivery compared with minor role in the sustainability of Danish meal service, and the the environmental impact of producing the meals, recyclable most efficient strategy to reduce the environmental impact of trays have been suggested in a revision of meal services. those activities would be to deliver all meals on a weekly basis However, the impact of plastic trays is so low that any impact rather than daily. reduction from switching to recyclable trays would be mean- This study suggests seven strategies to reduce the environ- ingless. An implicit study of this is therefore outside the scope mental impact of Danish meal services in terms of global of the present study. warming impact and monetized overall environmental impact: Weekly delivery of meals to customers rather than daily improves sustainability, and decreases transport cost, but it 1. Cutting the frequency of producing/ordering main meals may impose increased expenses for storage and preparation with beef in half will reduce impacts by 25–26% and 19– at the homes of the senior citizens. Most likely, however the 20%, respectively, where the small ranges mirror differ- senior citizens have their refrigerators/freezers running any- ences according to the applied functional units. way. This was outside the scope of our study. 2. Producing/ordering only beef meals from the better half of the beef recipes will reduce impacts by 6 and 5%, 4.5 Priorities in meal catering respectively. 3. Establishing a weekly beef-free day for all recipients and Besides the price of ingredients, the main priority in meal serving fish/seafood or vegetarian will reduce impacts by catering for senior citizens must be based on taste/ 8 or 9% for both impact categories. The increased sustain- acceptability (it is important to encourage the older people ability is mainly due to the indirect effect of having less to eat and drink; Nordin 2017), health (older people are more beef. vulnerable), and environmental impact (food is a major con- 4. Calculating environmental impacts of all meals and tributor to our overall environmental impact)—in that order— selecting to produce/order the more sustainable within but without the meal service neglecting any of the three as- each category more often. This strategy must be calculat- pects. Fortunately, low environmental impact often follows a ed for each meal service separately, which is outside the scope of this study. positive health impact of foods (e.g., Springmann et al. 2016), Int J Life Cycle Assess vegetable intake and the risk of cardiovascular disease, total cancer 5. Imposing a national beef tax as proposed by the Danish and all-cause mortality—a systematic review and dose-response me- Council of Ethics in 2017. ta-analysis of prospective studies. Int J Epidemiol 46:1029–1056 6. Converting daily to weekly deliveries will reduce impacts Caputo P, Clementi M, Ducoli C, Corsi S, Scudo G (2017) Food chain by 11% (global warming) and 14% (monetized overall evaluator, a tool for analyzing the impact and designing scenarios for the institutional catering in Lombardy (Italy). J Clean Prod 140: environmental impact), respectively, and eliminating all 1014–1026 waste of de facto meals reduce impacts by 2%. Cerutti AK, Ardente F, Contu W, Donno D, Beccaro GL (2018) 7. Restrict production of meals in all meal categories with Modelling, assessing, and ranking public procurement options extremely high impact (outliers). for a climate-friendly catering service. 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The International Journal of Life Cycle Assessment – Springer Journals
Published: Jun 4, 2018
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