The comminution of materials of bioorganic origin such as organic solids, biological agglomerates or micro-organisms is described in this work. The intent of this disintegration process is to release products, to improve the product quality or to enhance biological degradation processes. Special analytical techniques based on biochemical parameters are required in order to characterize the result of the comminution of organic materials. These techniques supplement techniques that are known from the comminution of brittle inorganic materials. The defined stressing of single particles can be used to characterize the comminution properties of solid bioorganic materials. The disintegration of micro-organisms has been investigated in the fields of biotechnological product release and biodegradability of wastewater sludges. It is possible to optimize the operational parameters of stirred ball mills based on stress intensity and stress number in order to reduce the energy input and to improve product release.