Currently,great attention is being paid to the utilization of biomass,such as feather keratins.It is imperative to extract and dissolve keratins from animal keratinous materials for exploitation of innovative biopolymers.However,most of the current processes are based on strong acid and alkali hydrolysis,chemical cleavage and other violent reactions,which are not eco-friendly and/or result in severe degradation and destruction of feather keratins.In this study,high density steam flash-explosion (HDSF) as an innovative pretreatment of biomass was firstly employed to treat feather waste.