The environmental impacts of food production and consumption are substantial, and therefore, it’s important that their impacts are investigated and communicated. Life cycle assessment (LCA) is one promising method to assess the environmental impacts of products, like food products. It’s a process to assess products' environmental impacts through their life-cycle, and it’s used, for example, in policy making, companies’ strategic decision making and when communicating products’ environmental impacts. LCA is used actively nowadays, for example, over the past year few Finnish food companies have decided to calculate and communicate their products’ carbon footprints using LCA. LCA methodology has clearly developed during the past decades. However, there isn’t a shared view on all of the methodological issues. In fact, one essential methodological challenge is allocation situation. In allocation situation all inputs and outputs, such as, green house gas emissions produced in the product system are to be distributed between the studied product and its co-products. For instance, when the studied product is milk it should be determined how the inputs and outputs produced in the dairy cattle farm are to be divided between the farm’s products: beef and raw milk. Furthermore, in the dairy factory it needs to be decided how the inputs and outputs are to be divided between the further processed milk and other dairy products produced in the factory. The aim of the thesis is to investigate the allocation situations in the LCAs of food, as well as, to present, compare and find weaknesses and strengths of different ways of handling allocation situations and ways of guiding them. This is done in a literature study and in a LCA case-study made for Finnish farmed rainbow trout. It was calculated that the choice of how to handle the allocation situation has a major impact on the environmental impacts directed to the product under investigation. For example, climate change impacts and eutrophication of water bodies caused by production of a trout fillet can halve or double depending on the choice of the allocation method. Several different allocation methods were indentified, including ways to avoid allocation and ways to allocate the inputs and outputs, for instance, on the basis of the products' prices. To improve the harmonization of food LCAs and to reduce subjectivity it is important that there is guidance when choosing the allocation method. However, the existing LCA guides investigated don’t give enough support for the allocation situations. They provide divergent instructions and recommendations; they aren’t very specific in the allocation instructions and they allow choosing almost any allocation method, and therefore there is clear need for more specific instructions. Thus, it is evident that there is need to discuss and agree on the suitability of allocation methods to be used in LCAs of different food products. Also, because of the existing uncertainty one should be really careful when communicating exact environmental impacts, instead, one should consider presenting environmental impacts in a more coarse scale, for example, by presenting the scale of the results when using different allocation methods.

Straw is an interesting renewable feedstock for various high-value products, such as textile fibers. However, straw encompass to soils maintains a good soil structure, fertility, and carbon storage. Despite the availability of previous research on this topic, uncertainties remain regarding the climate and soil impacts of straw collection. This study aims to show the carbon footprint (CF) of straw collection compared with that of soil encompass. The goal is to demonstrate uncertainties related to initial data and methodological assumptions on whether straw is regarded as a waste or a coproduct and illustrate where more measured data is needed. Life cycle assessment method was used to conduct this study and the data therein were gotten from literature. The results show that straw removal can lead to reduced greenhouse gas emissions in comparison to soil encompass because of reduced nitrogen fertilizing needs and subsequent N2O emissions. However, there is high uncertainty related to soil organic carbon (SOC) and N2O emission changes because of straw removal. It is also possible that greenhouse gas emissions increase due to straw removal. Straw seems to have a relatively low CF, especially when it is regarded as a waste. Coproduct interpretation significantly increases the emissions allocated for straw. Straw also stores carbon, and its total CF can be negative. The life cycle length of the straw-based end products determines how long carbon can be stored before it is released back into the atmosphere. Total greenhouse gas emission balance at a system level can be defined only when also straw refining and manufacturing of replaced final products are considered. Additional information is needed, especially on soil emissions (N2O and CH4) and impacts on SOC storage, to ensure the sustainability of straw-based products.

Current climate change is based on growth of greenhouse gas emissions, which are mainly due to human activities. Activities related to the global food system are responsible for about fourth of the global greenhouse gas emissions. Thereby, the emissions of the food system, which are related to the products that it provides, should be decreased. Greenhouse gas emissions of products can be estimated and communicated by the indicator of carbon footprint, whereas reduced greenhouse gas emissions of the products’ users, resulting from the emission improvements related to the products, can be presented by the carbon handprint. The aim of this master thesis was to calculate the carbon footprint of a Finnish food business’ meat containing food product. In addition, the food product’s meat component was replaced with different meat alternatives in order to assess the carbon handprints, and to compare the carbon footprint and carbon handprint as information providers of climate impacts. The main method used in this thesis was life cycle assessment, while methodology of carbon handprint was used as an additional method. Life cycle assessment was used to assess the carbon footprint, and it was applied according to the ISO standards of 14040 and 14044. Primary data for the study was collected from the Finnish food business through interviews by phone and e-mail, while secondary data was gathered from different sources. The actual calculation process of the carbon footprint and carbon handprints were executed by using Excel. The carbon footprint of the studied food product was found to be 1,20 kgCO2eq/one packaged food product, while the handprints based on the meat alternatives were found to be 0,27-0,39 kgCO2eq/one packaged product. Carbon footprint and handprint were found to be different as communication tools of climate impacts. In addition, they were discovered to have their advantages and limitations depending on the chosen point of view.

Municipal sewage contains significant embedded resources in the form of chemical and thermal energy. Recent developments in sustainable technology have pushed for the integration of resource recovery from household wastewater to achieve net zero energy consumption and carbon-neutral communities. Sewage heat recovery and fit-for-purpose water reuse are options to optimize the resource recovery potential of municipal wastewater. This study presents a comparative life cycle assessment (LCA) focused on global warming potential (GWP), eutrophication potential (EUP), and human health carcinogenic potential (HHCP) of an integrated sewage heat recovery and water reuse system for a hypothetical community of 30,000 people. Conventional space and water heating components generally demonstrated the highest GWP contribution between the different system components evaluated. Sewage-heat-recovery-based district heating offered better environmental performance overall. Lower impact contributions were demonstrated by scenarios with a membrane bioreactor (MBR) and chlorination prior to water reuse applications compared to scenarios that use more traditional water and wastewater treatment technologies and discharge. The LCA findings show that integrating MBR wastewater treatment and water reuse into a district heating schema could provide additional environmental savings at a community scale.

The objective of the literature review was to study the background of the greenhouse effect and map earlier studies of the greenhouse gas emissions of beef and other meat products. The objective of the literature review was also to study life cycle assessment used in previous studies to calculate the carbon footprint of food products, following the ISO 14040-standard. The aim of the experimental work was to calculate the carbon footprint of the beef processing chain in Finland from the farm gate to the consumer´s table. In addition the aim was to understand the importance of processing chain emissions compared to the whole beef production chain and different steps in the processing chain. The functional unit in the study was 1 kg of beef. The work was carried out by studying in detail one beef processing chain in Finland. Emissions were calculated based on real processing data from the collaborating company. The data was collected with an information form by visiting two production plants in the collaborating company and conducting further interviews. The carbon footprint of the beef processing chain was 1240 g CO2-ekv/kg meat. Most emissions were produced by refining (310 g CO2-ekv/kg meat), slaughtering (280 g CO2-ekv/kg meat) and transporting meat products to the consumer (210 g CO2-ekv/kg meat). The processing chain represents only 4 % of total beef production chain emissions as the emission from birth to the farm gate are, according to literature, over 30 000 g CO2-ekv/kg meat. In the future, the carbon footprint of the beef could be reduced mainly by developing the process from the birth to the farm gate. The results were very similar to previous research of the chicken processing chain in Finland (Katajajuuri et al. 2008). This was as expected because there were no significant differences in the processing chain. Previous studies of the beef processing chain were not available.