| Sinapic acid is the main phenolic compound present in mustard. Phenolic acids are aromatic secondary plant metabolites belonging to class of plant phenolics. Based on a lab-scale aqueous process for making protein isolate from yellow mustard flour, a membrane intensive scheme was developed to recover sinapic acid and water as a separate product from the waste stream obtained after separation of protein isolate as main product. Instead of solvents or adsorbents, a combination of ultrafiltration and diafiltration was used to fractionate sinapic acid from the protein and other components, and sinapic acid was then concentrated by reverse osmosis. A yield of approximately 62% of the total amount of sinapic acid in starting material, waste permeate and 43% based on the total amount of sinapic acid in defatted mustard flour was obtained in the reverse osmosis retentate. Finally a cleaning procedure was studied to recover the permeate flux after and results showed that 62% cleaning efficiency was obtained using NaOH, while 74% efficiency was attained when 2mM EDTA solution was used as a cleaning agent. |
