Membrane-based fractionation and concentration of sinapic acid from the waste permeate from yellow mustard protein effluent.

摘要

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.