Evaluation of Climate, Water, Land, and Biodiversity Impacts in Frozen Pizza Production: A Comparative Analysis of Bottom-up and Top-down LCA Approaches

Master’s Thesis by Pauline Kotzam

Abstract
The global food system is a major driver of climate change, freshwater depletion, land-sys-tem change, and biodiversity loss. Quantifying these impacts at the product level is essential for identifying mitigation opportunities. This thesis assesses the environmental impacts of a frozen salami pizza using two fundamentally different Life Cycle Assessment approaches: a process-based (Bottom-up) and an environmentally extended multi-regional input-output analysis (Top-down). Both approaches were applied from cradle to grave, with the functional unit defined as one packaged frozen salami pizza for home consumption. Four impact categories were analyzed: climate change, water use, land use, and biodiversity loss. The bottom-up LCA relied on primary data from the manufacturer and selected suppliers, combined with secondary data from ecoinvent 3.10.1, while the top-down assessment used the REX3 data-base. In addition, a nutritional Life Cycle Assessment framework combined with the Planetary Boundaries concept is used to evaluate the product’s environmental performance.
The results show that ingredient production dominates environmental impacts across all categories. Mozzarella and salami were identified as the main hotspots, confirming that animal-based ingredients disproportionately influence the environmental performance of processed foods. Climate change impacts are largely driven by livestock production, while water use, land use, and biodiversity loss are strongly linked to feed cultivation and region-specific agricultural pressures. The use phase contributes to climate impacts due to frozen storage and oven preparation. Scenario analysis indicates substantial reduction potential through reduced animal-based ingredients and the implementation of renewable electricity in production.
The comparison reveals differences between the two approaches. The bottom-up approach provides high product specificity but limited representation of global supply chains. In contrast, the top-down approach captures international upstream impacts but lacks product-level resolution. The findings demonstrate that combining the two approaches, supported by harmonized impact assessment methods, can yield more robust insights for sustainability as-sessments in the food sector.

Shifting Production Regions to Reduce Environmental Impacts: An MRIO Analysis of European Food Policies

Master’s Thesis by Nadine vom Hofe

This thesis analyzes the environmental consequences of European Union (EU) food consumption and explores policy options to mitigate climate change and biodiversity loss. Using an environmentally extended multi-regional input-output (EE-MRIO) model, the study calculates regionalized impact coefficients and assesses sectoral and geographical drivers of the EU’s food footprint. Scenario analyses tested shifts from high-impact imports to EU domestic production, climate and biodiversity taxes, and border adjustment mechanisms. Results show that beef has the highest environmental intensity per euro, with particularly high impacts in Brazil, Argentina, Namibia, and Botswana. Full substitution of imported high-impact beef with EU production achieved reductions up to 26% in climate impacts and 43% in biodiversity impacts of food —while tax-based measures reduced food impacts by 3–15%. However, these interventions carried socio-economic trade-offs, including rising beef prices and losses of workplaces in export-dependent regions. Overall, the findings highlight the potential of regionalized trade policies to reduce the EU’s beef-related environmental footprint, while also revealing significant socioeconomic trade-offs and emphasizing the need for globally coordinated action.

From Impact Assessment to Consumer Action: Designing a Loyalty Programme for Sustainable Food Choices based on LCA

Master’s Thesis by Antonia Krull

This thesis examines how Life Cycle Assessment (LCA) data can be integrated into consumer loyalty programmes to encourage sustainable food choices. Focusing on the intersection of environmental impact assessment, consumer behaviour, and retail incentives, the study designs a points-based rebate system that rewards lower-emission products. A consumer survey explores attitudes toward sustainability incentives, while impact simulations assess potential environmental benefits. Findings reveal that financial incentives, such as discounts, strongly influence purchasing decisions and can shift consumption towards more sustainable products without compromising nutritional value. Scenario modelling shows that widespread adoption of the Planetary Health Diet could reduce emissions by 32%, with discount-driven incentives achieving reductions of up to 60%. Barriers such as cognitive dissonance, price sensitivity, and limited awareness remain, but education and transparency significantly enhance engagement. The thesis provides a practical framework for retailers and policymakers to operationalize LCA-based loyalty programmes, supporting global climate targets and the UN Sustainable Development Goals.

Sustainability Assessment of the Event Landscape in a Corporate Environment: Three Case Studies in Collaboration with Oerlikon AM Europe GmbH

Master Thesis by Leila Shah Malakpour Khoshkbejari

This thesis investigates the sustainability of corporate events through a life cycle assessment (LCA) of three case studies within Oerlikon AM Europe GmbH: the 2023 Paris International Airshow, the 2023 Oerlikon Christmas Party, and the 2024 Annual General Meeting. Using a bottom-up LCA approach and the Ecoinvent database, the study evaluates greenhouse gas (GHG) emissions from transportation, food, and energy. Results show transportation as the largest contributor across events, followed by food and energy. The Paris Airshow generated the highest emissions (26.0 kg CO₂eq per capita per day), mainly due to international travel, while smaller internal events still exhibited notable impacts from food and transport choices. Comparisons with global and regional benchmarks reveal that all events exceeded the 1.5°C emission target. The study recommends strategies such as reducing air travel, promoting virtual participation, offering more plant-based food, and improving energy efficiency to align corporate event practices with climate goals.