Food waste in the food service sector : Quantities, risk factors and reduction strategies

An estimated one-third of all food produced is wasted, meaning that much of the negative environmental impact caused by food production is in vain. Global ambitions to reduce food waste include halving the levels by 2030, while the new EU food strategy views reducing food waste as a key issue in achieving a sustainable food system. This thesis presents detailed information on the volumes of food waste, where it occurs, why it occurs and what can be done to reduce it. The information originated from 1189 kitchens operating in establishments such as canteens, care homes, hotels, hospitals, preschools, schools and restaurants throughout Sweden, Norway, Finland and Germany. The results indicated that approximately 20% of food served in the catering sector is wasted, although there is large variation, with canteens reporting 50±9.4 g/portion of food waste and restaurants 190±30 g/portion. To identify risk factors and reasons for food waste, a more detailed subset of data on Swedish preschools and schools was analysed. Some of the risk factors identified related to kitchen infrastructure and guest age, which could be difficult or expensive to tackle as a first option. The main risk factor was the amount of food prepared relative to the number of guests attending, an issue that kitchens can tackle by forecasting. This thesis demonstrated the potential of forecasting attendance as a tool in planning catering operations. The current business-as-usual scenario, where food is prepared for all pupils enrolled, results in a mean error of 20-40%, whereas the best forecasting case, using neural network models, resulted in a mean error of 2-3%. However, forecasts can underestimate demand, creating shortages, so some margin must be added in practical use. Providing kitchens with information about roughly how many guests will attend a meal, plus a sufficient margin, and encouraging them to serve food from a backup stock in cases of forecast underestimation would overcome the problems of shortages, reduce food waste and contribute to a sustainable food system

Making food waste illegal in Sweden – Potential gains from enforcing best practice in the public catering sector

Food waste is an inefficiency problem that needs to be reduced significantly to achieve a sustainable food system. Best practices and knowledge are available on how to reduce waste but large volumes of food are still wasted every year, so policies that support or enforce broader implementation of best practices are needed. One policy that could be used to push implementation and successful use of best practices to reduce food waste is the Swedish Environmental Code, which states that all actors must consider every possibility to reduce the amount of waste generated in any facility, unless this is unreasonably expensive. However, there is no clear definition on the actual waste reduction needed to comply with this requirement, so it is not enforced in practice.This study explored the potential gains of applying the Environmental Code, potential benchmarking thresholds for illegal levels of food waste and best voluntary practices that can achieve low levels of food waste. The Environmental Code is applicable to most operator food handling systems, and was assessed here using the Swedish public catering sector as a case. All 290 Swedish municipalities were asked to provide raw data for the study and some agreed, resulting in a dataset covering 458 public catering units serving care homes, schools and preschools. The data were analysed to identify different permissible levels of food waste, while the best canteens provided information on their best practices to keep food waste low.The results showed that with best voluntary practice for each type of catering unit, overall food waste would be reduced by up to 76 %. Best voluntary practices used by the best-performing canteens were identified as: ‘reusing buffet leftovers’, ‘adjusting recipes based on previous consumption’, ‘advising guests to start with small tasting portions’, ‘setting goals for waste reduction’ and ‘serving smaller volumes in buffet containers and refilling more often’. All these actions can realistically be implemented as standard practices by public catering organisations. The present analysis could not confirm that all these actions have actually been implemented, or to what extent, but practical implementation of identified best voluntary practices meeting stated benchmarks is recommended.The Environmental Code is technology-neutral and goal-oriented and participating food business operators are not forced by law or official regulations to introduce resource-saving measures, but this study shows that some measures can lead to a large reduction in food waste. The study does not show whether harsh, i.e. costly, measures can be enforced on businesses, which can only be determined by case law (court practice). However, in the specific cases in this study, measures that could have been enforced based on the Environmental Code would have led to at least 76 % reduction in food waste. This would be a major step towards a sustainable food system

Automated quantification tool to monitor plate waste in school canteens

Automated tools for waste quantification hold promise in providing preciser understanding of food waste. This study evaluated a tool to quantify plate waste in primary school canteens. It encompassed data from 421,015 instances of food wastage. The evaluation revealed high accuracy, with the tool’s plate waste detection falling within ±10% of manual recordings. However, the tool estimated 40% fewer individual guests compared to manual entry due to not all students wasting food. As a result, the automatically collected data indicated a 35% higher waste-to-guest ratio. The findings showed that a minority of students (20%) accounted for a majority (60%) of plate waste. Halving the waste generated by this group would reduce overall plate waste by 31%, emphasizing the importance of tailored interventions for high-profile wasters rather than applying general measures to all students. Targeting areas with the greatest potential can contribute to a more sustainable food system with reduced waste

Investigating goal conflicts in menu planning in Swedish school catering on the pathway to sustainable development

The 260 million publicly funded school meals served annually in Sweden generate 21.000 tons of food waste. At national level, school meals should meet the goal of food waste reduction, together with various other goals such as meeting nutritional requirements, being environmentally friendly and, most importantly, achieving high acceptance among schoolchildren. There is a preconception among kitchen staff that the most popular school meals drive food waste in Swedish school catering and that vegetarian dishes increase food waste, despite being less popular than meat options. By applying mixed methods, this study investigated possible goal conflicts between reduced food waste, high acceptance, and vegetarian options on the lunch menu. An overall aim was to gain knowledge on how lunch menus could be adapted for increased sustainability. Kitchen staff from 10 Swedish primary and secondary schools were interviewed to identify the most popular and unpopular meals, and food waste quantification data and lunch menus from 61 school canteens were analyzed. The results showed that, while the common perception of popular and vegetarian meals creating most waste was held by kitchen staff, it proved to be untrue. In fact, popular school meals and vegetarian options generated less waste than unpopular meals. A vegetarian paradox was detected in interviews, with vegetarian options considered unpopular but with several vegetarian options among the most popular dishes. Thus, school-catering units should stop serving unpopular meals and shift their focus to serving popular nutritious meals, including popular plant-based options, as part of efforts to make school meal schemes more sustainable

Food waste reduction and economic savings in times of crisis: The potential of machine learning methods to plan guest attendance in Swedish public catering during the Covid-19 pandemic

Food waste is a significant problem within public catering establishments in any normal situation. During spring 2020 the Covid-19 pandemic placed the public catering system under greater pressure, revealing weaknesses within the system and generation of food waste due to rapidly changing consumption patterns. In times of crisis, it is especially important to conserve resources and allocate existing resources to areas where they can be of most use, but this poses significant challenges. This study evaluated the potential of a forecasting model to predict guest attendance during the start and throughout the pandemic. This was done by collecting data on guest attendance in Swedish school and preschool catering establishments before and during the pandemic, and using a machine learning approach to predict future guest attendance based on historical data. Comparison of various learning methods revealed that random forest produced more accurate forecasts than a simple artificial neural network, with conditional mean absolute prediction error of <0.15 for the trained dataset. Economic savings were obtained by forecasting compared with a no-plan scenario, supporting selection of the random forest approach for effective forecasting of meal planning. Overall, the results obtained using forecasting models for meal planning in times of crisis confirmed their usefulness. Continuous use can improve estimates for the test period, due to the agile and flexible nature of these models. This is particularly important when guest attendance is unpredictable, so that production planning can be optimized to reduce food waste and contribute to a more sustainable and resilient food system

Environmental Assessment of Upgrading Horticultural Side Streams—The Case of Unharvested Broccoli Leaves

: To facilitate transition to a sustainable food system, it is necessary to address food losses. A large proportion of waste occurs during primary production, with large quantities of edible crop parts left in the field at harvest. One such product is broccoli, where normally only around one-third of the edible parts of the plant are harvested in Sweden. Much of the broccoli plant consists of edible leaves and this side stream represents an unused resource with great potential. This study assessed the potential environmental savings that can be achieved by utilising broccoli side streams as a powder in soups and bread. Consequential and attributional life cycle assessments were conducted, based on scenarios relevant for growers in southern Sweden. The results showed that the scenario with the largest saving potential was to process the broccoli side streams into a powder for use in broccoli soup. The main saving was due to substitution of imported broccoli powder, which was assumed to be produced from broccoli florets using a more fossil-based energy mix. The second best scenario was to use the side-stream broccoli powder as a wheat substitute in bread but, since wheat flour is less resource-demanding than imported broccoli powder, the emission savings were lower in this case. However, replacing wheat flour with a vegetable-based product could provide additional health benefits that are important in achieving a healthy, locally available, and environmentally friendly diet suitable for a sustainable food system

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

Matsvinn i storkök

Matsvinn är ett problem som uppkommer längs hela livsmedelskedjan och leder till att mat produceras i onödan. Denna onödiga matproduktion bidrar till utsläpp som påverkar miljön samt förbrukar ändliga resurser. Matsvinn som uppstår i storkök används ofta till att producera biogas för att ta tillvara energin i maten, men trots denna återvinning är det ändå ett stort slöseri av resurser att producera bränsle av ätbar mat som befinner sig i slutet av värdekedjan. Därför finns det ett stort behov av att förebygga matsvinn för att få en mer hållbar livsmedelskedja. Ett första steg mot att hitta metoder för att förebygga matsvinn i storkök är att kvantifiera matsvinnet och identifiera problemområden så att olika åtgärder kan sättas in där de har störst effekt. Syftet med denna studie var därför att kartlägga kasserade kvantiteter mat för att identifiera problemområden med högt svinn. Detta genomfördes i Sala kommun där samtliga kök inom skola, förskola och äldreomsorg deltog. Mätningar av matsvinn genomfördes under tre perioder med fyra mätveckor i varje period och fokuserade främst på tallriksavskrap samt rester från serveringen. Matsvinnet jämfördes med antalet ätande gäster vilket baserades på antalet använda tallrikar. Svinnet jämfördes även med den serverade matens massa för att få fram fler relativa nyckeltal. Summerat för alla undersökta kök kasserades 75 g mat per serverad portion under mätperioden. Detta motsvarade 23 % svinn i relation till den serverade matens massa. Svinnet bestod till största delen av serveringssvinn (64 %) följt av tallrikssvinn (33 %) och övrigt (3 %). Svinnet var ojämnt fördelat och det fanns betydande variation mellan olika kök. Även beroende på vilka gäster som serverades hade betydelse för svinnet då äldreboenden hade högst svinn med 90 g per serverad portion, följt av skolköken som hade 79 g svinn per serverad portion och förskolor med 51 g svinn per serverad portion. Identifierade problemområden var främst specialkosten som var kategorin av mat vilken hade högts svinn i relation till den serverade matens massa. I övrigt var det främst skolköken som identifierade som ett problemområde då de bidrog till den största andelen av kommunens sammanlagda svinn samt hade betydligt högre svinn per serverad portion än exempelvis förskolor. Det fanns en betydande variation mellan olika kök och det är uppenbart att problemområden behöver identifieras på köksnivå snarare än på aggregerad kommunnivå för att kunna hitta åtgärder som löser de problem enskilda kök visar upp. Genom att lösa enskilda köks problem bör det finnas god potential att minska matsvinnet och därmed bidra till en mer hållbar livsmedelskedja

Matsvinn i storkök

Matsvinn är ett problem som uppkommer längs hela livsmedelskedjan och leder till att mat produceras i onödan. Denna onödiga matproduktion bidrar till utsläpp som påverkar miljön samt förbrukar ändliga resurser. Matsvinn som uppstår i svenska storkök används ofta till att producera biogas för att ta tillvara energi och näringsämnen i maten. Trots denna återvinning är det ändå ett stort slöseri av resurser att producera bränsle av ätbar mat från slutet av värdekedjan. Därför finns ett stort behov av att förebygga matsvinn för att få en mer hållbar livsmedelskedja. Det florerar ett flertal råd om vad storkök bör göra för att minska matsvinnet eller vad de bör undvika att göra men få av dessa råd tycks ha studerats närmare för att utröna hur stor påverkan de faktiskt har på svinnet i storkök. Syftet med denna studie var därför är att undersöka om och i så fall hur mycket sex olika riskfaktorer och åtgärder påverkar matsvinnet i storkök. För att beräkna effekten av dessa riskfaktorer och åtgärder användes insamlad statistik från Sala kommun där samtliga kök inom skola, förskola och äldreomsorg ingick. Mätningarna av matsvinn kompletterades med ytterligare information om antalet ätande samt en enkätundersökning som frågade skolelever om vilka maträtter som föredrogs respektive inte föredrogs. Analysen av respektive åtgärd och riskfaktor gjordes genom att jämföra det genomsnittliga svinnet när åtgärden varit applicerad med medelvärdet då åtgärden inte varit applicerad. Av de sex riskfaktorerna och åtgärderna som analyserats i denna studie var det användandet av mottagningskök och serverandet av fler lunchalternativ än ett, som genererade mest svinn. Information till elever om mätning och att ha ett flexibelt alternativ i menyn hade en reducerande effekt på svinnet, dock var effekten inte lika stor som de två första riskfaktorerna. Att större enheter genererar mer svinn var endast sant för tallrikssvinn men totalt sett minskade svinnet något när storleken på köken ökade eftersom serveringssvinnet var lägre i stora kök. Att populära maträtter skulle resultera i extra mycket svinn kunde inte beläggas då resultaten pekade på motsatsen, nämligen att populära maträtter kasseras i mindre omfattning än opopulära maträtter. Eftersom de analyserade riskfaktorerna och åtgärderna korrelerar olika starkt med totalt svinn är en rekommendation att kommuner på lång sikt bör konvertera mottagningskök till tillagningskök, samt begränsa antalet serverade lunchalternativ. På kort sikt bör kommunerna lägga in ett flexibelt alternativ i menyn och informera elever om matsvinnsmätningar, vilket då förutsätter att mätningar faktiskt genomförs. Kommuner behöver däremot inte vara oroliga att populära maträtter eller att stora enheter ska generera mer svinn

Food waste reduction in the public catering sector

Food waste is attracting global attention and there are stated ambitions to halve food waste by 2030. This thesis presents detailed information on quantities of food waste in the food service sector, with particular focus on the Swedish public catering sector. It examines where waste occurs, why it occurs, what can be done to reduce it and whether the ambitions to halve food waste by 2030 is achievable. The information collected covered the period 2010-2020 and originated from 3 386 kitchens operating in canteens, care homes, hotels, hospitals, preschools, schools and restaurants throughout Sweden, Norway, Finland and Germany. The results indicate that 18% of food served in the sector is wasted, although there is large variation between catering units. The main risk factor for food waste generation was identified as being amount of food prepared relative to number of guests attending, an issue that kitchens can tackle by improved forecasting. Forecasting as a waste reduction measure was tested in Swedish school canteens, alongside awareness campaigns, introducing tasting spoons and a plate waste tracker providing feedback to guests to nudge their behaviour. All these measures reduced food waste, but only forecasting and the plate waste tracker reduced total food waste more than in a set of reference canteens that had none of these measures in place. The mass of food waste generated in Swedish preschools, primary schools and secondary schools has declined by 25% since 2016. The amount of food waste to be halved by 2030 was estimated to 21,000 t for preschools and schools, which corresponds to 21 g/guest. Systematic work on food waste reduction, with quantification as a core step to evaluate current ambitions, is necessary to achieve a more sustainable food system