The test material is mixed with fresh biowaste in a population and introduced into a defined composting environment. A natural ubiquitous microbial population will start the composting process spontaneously and the temperature will increase. The composting mass is regularly turned over and mixed. Temperature, pH-value, moisture content and gas composition are regularly monitored. They have to fulfil certain requirements to ensure sufficient and appropriate microbial activity. The composting process is continued until a fully stabilized compost is obtained. This is usually the case after 12 weeks