Phenolic profile and antioxidant properties of a crude extract obtained from a brewery waste stream

► Characterization of a natural extract for use as a food additive. ► Phenolics of the extract were identified and quantified using HPLC-DAD-ESI-TOF(MS). ► Flavonoids and phenolic acids are the main compounds in the natural extract. ► Natural extract exhibited remarkable antioxidant activity. ► Natural extract could replace synthetic additives in food industry.