Extraction and preparation of cellulose nanocrystal from Brewer's spent grain and application in pickering emulsions

In recent years, the search for novel Pickering stabilizers has attracted much interest in the food, cosmetic and pharmaceutical industries. In this work, brewer's spent grain cellulose (BSGC) was successfully extracted by diluted acid, alkaline and bleaching treatments, and then brewer's spent grain cellulose nanocrystal (BSGCNC) were obtained by acid hydrolysis treatment of BSGC. The properties of the BSGCNC were characterized, and the results showed that the BSGCNC had a rod-like structure with high crystallinity (67.09%). Then the emulsification properties of BSGCNC were evaluated by different concentrations and water-oil ratios, and the results showed that BSGCNC were able to form stable Pickering emulsions. This study suggested that cellulose nanocrystal (CNC) could be extracted from brewer's spent grain which was used as food waste, as a stabilizer for Pickering emulsions.