Among the methods commonly used for quantifying food waste in households, there are limitations that affect the reliability of quantification results. To address these, this study used an automated quantification tool to objectively and with high precision quantify food waste in 28 Swedish households for an extended period, reaching a total of 3945 quantification days. The results showed that the average daily waste amounted to 0.159 kg per person. Recorded food waste displayed a large variation between days, weeks and months, suggesting that long-term quantification is necessary for precision. As the results indicated, between 115 and 569 quantification days is necessary to provide an average estimate with a ± 10 % precision. This study presents empirical evidence demonstrating the feasibility and opportunities of automated food waste quantification, emphasizing the importance of extended measurement periods, high-frequency data collection, and minimal user intervention on designing effective waste tracking systems.

Background: Renewable materials made using environmentally friendly processes are in high demand as a solution to reduce the pollution created by the fashion industry. In recent years, there has been a growing trend in research on renewable materials focused on bio-based materials derived from fungi. Results: Recently, fungal cell wall material of a chitosan producing fungus has been wet spun to monofilaments. This paper presents a modification for the fungal monofilament spinning process, by the development of a benign method, dry gel spinning, to produce continuous monofilaments and twisted multifilament yarns, from fungal cell wall, that can be used in textile applications. The fungal biomass of Rhizopus delemar, grown using bread waste as a substrate, was subjected to alkali treatment with a dilute sodium hydroxide solution to isolate alkali-insoluble material (AIM), which mainly consists of the fungal cell wall. The treatment of AIM with dilute lactic acid resulted in hydrogel formation. The morphology of the hydrogels was pH dependent, and they exhibited shear thinning viscoelastic behavior. Dry gel spinning of the fungal hydrogels was first conducted using a simple lab-scale syringe pump to inject the hydrogels through a needle to form a monofilament, which was directly placed on a rotating receiver and left to dry at room temperature. The resulting monofilament was used to make twisted multifilament yarns. The process was then improved by incorporating a heated chamber for the quicker drying of the monofilaments (at 30⁰C). Finally, the spinning process was scaled up using a twin-screw microcompounder instead of the syringe pump. The monofilaments were several meters long and reached a tensile strength of 63 MPa with a % elongation at break of 14. When spinning was performed in the heated chamber, the tensile strength increased to 80 MPa and further increased to 103 MPa when a micro-compounder was used for spinning. Conclusion: The developed dry gel spinning method shows promising results in scalability and demonstrates the potential for renewable material production using fungi. This novel approach produces materials with mechanical properties comparable to those of conventional textile fibers.