Composting of vegan kitchen waste: applicability assessment

Kitchen waste from vegan households can be a raw material for home or backyard composting. However, the use of waste without components like eggshells or meat can constitute several problems, including the decrease of the process temperature and the content of Ca, N, K, Mg, Mn, Na, and S. The scientific aim of the study was to investigate possibility of production and applicability of vegan compost (VC) produced from kitchen waste during 12-weeks backyard composting. The VC properties have been compared to the traditional compost (TC), made from plant- and animal-origin waste materials. Analyzes showed that VC and TC have similar properties, reaching a pH close to 7.5, respiratory activity AT4 <2 mgO2‧(g dry mass)-1and dry matter content of ~79%. VC didn’t show any phytotoxic effect on garden cress; it was characterized by the highest seed germination (100%) and it stimulated the growth of plants’ roots. It was characterized by a higher content of phosphates, P and K, and achieved a lower BOD/COD ratio, demonstrating its maturity and low rotting potential. VC also contained less chloride, Ni, and Pb and showed a lower potential for nitrates leaching. The values of contaminants contained in VC samples didn't exceed the limit values for organic fertilizers. Therefore, studies indicated that plant-based kitchen waste can be a valuable substrate to produce compost and proved that vegan households, restaurants, and cafes are not disqualified from implementing a circular economy by using them assecondary material.