In order to meet global goals of reducing food waste, feasible monitoring methods to verify the impact of reduction measures are needed. In this study, a method was developed for gathering food waste data related to the primary production of fruit and vegetables using a questionnaire for farmers. A data collection form was planned and tested for this purpose. Data was collected on the volumes of different uses of yields and the reasons why part of the yield does not end up in food use. The crop species that were included in this pilot study were food potatoes, carrots, white cabbage, and strawberries. In primary production, the share of food use of the total yield was highest for potatoes (96%) and lowest for carrots (72%). In the case of strawberries and white cabbage, 86% and 90% were used as food, respectively. In the future, it is recommended that this kind of survey be added to annual crop production surveys that cover agricultural and horticultural enterprises in Finland. To improve the response rate and decrease the reporting load of farmers, it is important that the questionnaire is designed to be as easy as possible to answer.

Purpose: Currently, there is no consensus on how the impacts of land use on the soil organic carbon (SOC) stocks would be best quantified within life cycle assessments (LCA) of agricultural products. The impacts of different decisions were tested within a model-based assessment of soil carbon changes on the life cycle global warming impact for spring wheat produced in two example regions in Finland (Southwest Finland and Northern Savonia) on mineral fields. Methods: Global warming impact for spring wheat was assessed, including CO₂ emissions due to the SOC change. The SOC change assessment was made with the soil carbon model Yasso07. The effects of assumptions on land use history were tested, i.e. the initialisation of the model and time horizon of the analysis (20 or 100 years) on the SOC change estimates. Other greenhouse gas emissions contributing to the global warming impact of spring wheat production were assessed using general LCA methodology taking into account the greenhouse gas emissions caused by the production of input materials and fuels, as well as direct and indirect N₂O emissions from the soil due to fertilising and the decomposition of crop residues and organic matter, nitrogen leaching and volatilisation and lime application. Results and discussion: The selection of the model initialisation method and timeframe remarkably affected the SOC change estimates. The global warming impact of wheat production, without accounting for SOC changes, was 0.68 and 0.89 kg CO₂-eq/kg yield in Southwest Finland and Northern Savonia, respectively. The impact of SOC stock changes on the total global warming impact varied from –4 to 5% in Southwest Finland and from 5 to 21% in Northern Savonia, depending on the assumptions used to initialise the model or the timeframe applied in the analysis. Adding a cover crop as a means to increase the SOC stock removed between –67 and –26% of the total global warming impact in both regions. Conclusions: It is essential that all the decisions made in the analysis are transparently reported and communicated. The choice of assumptions regarding the reference state, model initialisation and time horizon of the assessment period should be made based on the scope and goal definition of the LCA study.

Interest in insect production for human consumption is growing in many European countries, including Finland. One of the main justifications for insect-based food products is their lower environmental burden compared to traditional livestock products; another is the need for new protein sources for animal feed and human consumption. In this study, we investigated the global warming potential (GWP) of the potential future industrial scale mealworm production in Finland, using existing data on input needs of mealworm production in the Netherlands and previous life cycle assessment studies of Finnish feedstocks and energy sources. We compared three scenarios, of which one was based on feeding with a commercial feeding mixture, the second on feeding with food industry by-products and the third on the use of low-emission energy sources in combination with feeding with food industry by-products. In all three scenarios, feed crop production and direct heating energy were responsible for at least 95% of the total GWP. Especially the use of low-emission energy sources appears to have potential in reducing the greenhouse gas emissions of insect production.

Purpose: A transition to more plant-rich diets is an effective way to reduce the climate impact of a diet. Using a whole-diet approach, we studied how partial replacement of animal-sourced with plant-sourced proteins affected the dietary climate impact while simultaneously considering diet-related health biomarkers. Methods: In a 12-week randomised controlled trial, 107 women and 29 men were assigned into three diet groups (ANIMAL, 50/50, PLANT) with animal-to-plant-protein ratios of 70/30, 50/50, and 30/70, respectively. Life-cycle-assessment-based coefficients for foods were used to assess the climate impact of the diet groups, based on four-day food records. Correlations between climate impact and biomarkers were assessed. Results: The climate impact (CO₂ eq.) for PLANT was 3.32 kg per day, 3.05 kg per 2,000 kcal, and 0.04 kg per gram of protein, for 50/50 4.34, 4.20, and 0.05 kg, and for ANIMAL 4.93, 4.94, and 0.06 kg, respectively (p < 0.05 for all except ANIMAL vs. 50/50 /g protein and /2,000 kcal). Climate impact correlated weakly positively with colorectal cancer risk markers and a positive status of bone turnover, but not with cardiometabolic risk markers. Animal-based iron intake and climate impact (per 2,000 kcal) had a strong positive correlation 0.70 C.I. [0.60, 0.77], while saturated fat (0.29 [0.13, 0.44]) and calcium (0.37, [0.22, 0.51]) intake had a weak positive correlation, and fibre intake (− 0.37, [− 0.51, − 0.21]) a weak negative correlation with climate impact. Conclusion: Replacing animal-sourced proteins with plant-sourced proteins reduced the climate impact of the diet. The relationship between climate impact and biomarkers was more ambiguous indicated by both beneficial and harmful indicators within lower climate impacts. Clinical trial registry: NCT03206827; registration date: 2017–06–30.

Increasing demand of fossil-free fuels in the transport sector drives towards using new biomass sources in fuel production. Municipal waste as a substrate is used in many countries in biomethane production, but the amount of waste can cover only a small portion of the fuel used. In Europe, the new renewable energy directive (RED II) was established December 2018 to ensure the sustainability of renewable fuels. The directive includes typical and default greenhouse gas (GHG) emissions for several potential substrates, such as biogas from manure or maize silage, which the biogas plants can use to verify their emissions directly or to calculate their emissions using the methods provided. However, such default value for grass silage as biogas substrate is lacking. We defined the conditions needed to fulfil the sustainability criteria of the directive when producing biomethane for vehicle fuel using grass silage as the feedstock in Finland. The emission reduction targets are not easy to achieve in Finland when using grass cultivated exclusively for energy production. The reduction targets can be achieved, however, if the grass is cultivated due to an improved crop rotation, where the grass is co-digested with manure and/or energy sources with zero emissions for the process can be applied.

An indicator of nutrient use efficiency through the entire food chain has been lacking. This article proposes a nutrient footprint method to estimate the efficiency of using both nitrogen (N) and phosphorus (P) in animal production chains following Life Cycle Assessment (LCA).