Production efficiency of animal feed obtained from food waste in Japan

Transforming food waste into animal feeds: an in-depth overview of conversion technologies and environmental benefits

Food waste is a global concern, with significant quantities of edible food being discarded every day. However, innovative conversion technologies have emerged to effectively transform this waste into valuable animal feed. This review paper provides a comprehensive examination of the conversion technologies used to transform food waste into animal feed, along with an analysis of the environmental benefits associated with these processes. The paper delves into various conversion methods such as anaerobic digestion, insect-based conversion, and microbial fermentation along with exploring their mechanisms and suitability for converting food waste into valuable animal feed resources. Additionally, the environmental benefits, including waste reduction, greenhouse gas emission reduction, and resource conservation, are discussed in detail. The review highlights the potential of these technologies to address the pressing issue of food waste while contributing to a more sustainable and resource-efficient food system. The findings of this review emphasize the importance of adopting and further developing these conversion technologies as a means to mitigate environmental impacts, promote circular economy principles, and enhance the overall sustainability of the food and agriculture sector.

Production efficiency and cost reduction potential of biodiesel fuel plants using waste cooking oil in Japan

Biodiesel fuel (BDF) is a potentially carbon-neutral fuel that could play a potentially important role in preventing global warming. However, its high production cost poses a challenge for many BDF producers. To establish an efficient method for BDF production and increase its cost competitiveness, the production efficiencies of 35 BDF plants in Japan, which produce BDF from waste cooking oil, were evaluated. Moreover, the cost reduction potential associated with improved efficiency was estimated. The empirical analysis revealed that (1) approximately 92% of the BDF plants have inefficient production; (2) they exhibit two predominant types of inefficiencies, technical and scale inefficiencies, and (3) improvement of production inefficiency can lead to an average production cost reduction of 3.52 yen per liter of BDF. To increase the production efficiency, it is important to improve the quality of the waste cooking oil used and increase the production scale. It is recommended that operators of inefficient BDF plants learn the production activities of the most efficient plants identified in this study. Furthermore, government policies focused on efficient BDF plants are essential to increase BDF production with limited resources.

Friend or Foe? The Role of Animal-Source Foods in Healthy and Environmentally Sustainable Diets

Scientific and political discussions around the role of animal-source foods (ASFs) in healthy and environmentally sustainable diets are often polarizing. To bring clarity to this important topic, we critically reviewed the evidence on the health and environmental benefits and risks of ASFs, focusing on primary trade-offs and tensions, and summarized the evidence on alternative proteins and protein-rich foods. ASFs are rich in bioavailable nutrients commonly lacking globally and can make important contributions to food and nutrition security. Many populations in Sub-Saharan Africa and South Asia could benefit from increased consumption of ASFs through improved nutrient intakes and reduced undernutrition. Where consumption is high, processed meat should be limited, and red meat and saturated fat should be moderated to lower noncommunicable disease risk-this could also have cobenefits for environmental sustainability. ASF production generally has a large environmental impact; yet, when produced at the appropriate scale and in accordance with local ecosystems and contexts, ASFs can play an important role in circular and diverse agroecosystems that, in certain circumstances, can help restore biodiversity and degraded land and mitigate greenhouse gas emissions from food production. The amount and type of ASF that is healthy and environmentally sustainable will depend on the local context and health priorities and will change over time as populations develop, nutritional concerns evolve, and alternative foods from new technologies become more available and acceptable. Efforts by governments and civil society organizations to increase or decrease ASF consumption should be considered in light of the nutritional and environmental needs and risks in the local context and, importantly, integrally involve the local stakeholders impacted by any changes. Policies, programs, and incentives are needed to ensure best practices in production, curb excess consumption where high, and sustainably increase consumption where low.

Bioconversion of food waste to crayfish feed using solid-state fermentation with yeast

In order to realize the value-added utilization of food waste (FW), the preparation of crayfish (Procambarus clarkii) feed by yeast fermentation was investigated. Firstly, the suitable fermentation condition was obtained through a single factor experiment as follows: the initial moisture of the FW was adjusted to 60% with bran and inoculated with a 2% yeast mixture (Saccharomyces cerevisiae, Candida utilis, and Yarrowia lipolytica, 3:2:1) followed by aerobic solid-state fermentation for 7 days. The crude protein and acid-soluble protein contents in the fermented feed were 25.14% and 5.16%, which were increased by 8% and 140.67%, respectively. The crude fat content was 0.74%, decreased by 68.29%. The content of antioxidant glutathione (571.78 μg/g) increased 63.33%, and the activities of protease and amylase increased nearly 9 and 3 times, respectively. The maximum degradation rates of aflatoxin B1, zearalenone, and deoxynivalenol were 63.83%, 77.52%, and 80.16%, respectively. The fermented feeds were evaluated by substituting (0%, 10%, 30%, 50%, and 100%) commercial diet for crayfish (30-day culture period). When the replacement proportion was 30%, the weight gain of crayfish reached 44.87% (initial body weight 13.98 ± 0.41 g), which was significantly increased by 10.25% compared with the control (p = 0.0005). In addition, the lysozyme and SOD enzyme activities in crayfish hepatopancreas were also increased significantly. Our findings suggest that yeast-fermented feed from FW can replace 30% of crayfish's conventional diet, which may improve crayfish's antioxidant capacity and enhance non-specific immunity by providing molecules such as glutathione.

Triple Bottom-Line Evaluation of the Production of Animal Feed from Food Waste: A Life Cycle Assessment

This study applies a triple bottom line (TBL) framework that incorporates the environmental, economic, and social impacts of producing animal feed from food waste (FW) collected at the post-consumption stage of the food supply chain. The environmental bottom line (BL) is conducted using life cycle assessment (LCA), the economic BL is calculated using the net present value (NPV), while the social BL is assessed using the strengths, weaknesses, opportunities, and threats (SWOT) analysis. The results within the environmental BL indicate that at a 13.8% recovery rate, animal feed produced from a ton of FW saves 0.33 m² equivalent of crop land but requires 3.5 tons of water compared to 0.9 tons and 0.78 tons for landfilling and incineration for FW treatment respectively. In addition, the production of animal feed from one ton of FW emits 1064.6 kg CO₂-eq, compared to 823.6 kg CO₂-eq using landfilling and 781.9 kg CO₂-eq when incinerated. The economic BL indicates a profit of $3.65/ton from incinerating FW, compared to cost of $93.8 and $137.6 per ton for animal feed production and landfilling of FW respectively. The analytic hierarchy process (AHP) is applied to integrate the TBL scores and rank the scenarios accordingly. AHP recommends animal feed and incineration over landfilling by a fourfold higher score. A simulation using an augmented simplex lattice mixture (ASLM) design recommends incineration with energy recovery over animal feed production from FW collected at the consumer stage. Sensitivity analysis indicates that the production of animal feed from FW is environmentally feasible if the safe recovery rate exceeds 48%, is which possible for FW collected at early stages of the food supply chain.