Evaluation of Reverse Osmosis Membranes in Concentration of Beetroot Peel Extract

Abstract

Recovery of valuable products from organic wastes with conventional extraction method plus modern separation technology is becoming popular in solid waste management. The major attention of this project was to test the efficiencies of two different types of reverse osmosis membranes (RO99 and X20) on juice concentration extracted from peel of beetroot which is "waste". The extractions of beetroot peel were completed using water and ethanol-water (15 v/v%) solvents at 22 °C for 60 minutes. The applied transmembrane pressure, temperature, and recirculation flow rate of membrane separation process were 40 bars, 30 °C, and 400 L/h, respectively. Quantifications of valuable compounds were detected using spectrophotometer. The permeate flux profiles were investigated and lower permeate flux was experienced with RO99 compared to X20 in both methods. Additionally, from the aspect of efficiency, RO99 outstripped X20 membrane on concentration of some compounds such as betalains, and phenolic components. Betaxanthin, betacyanin, antioxidant and TPC contents in final retentates of RO99 membrane concentration were as follow: 292.47±1.93 mg/L, 499.03±1.3 mg/L, 1133.15±25.74 mg/L,1243.96±106.56 mg/L (water solvent) and 337.26±4.31 mg/L, 585.2±5.83 mg/L, 698.55±22.53 mg/L, 1268.87±48.69 mg/L (ethanol-water solvent), respectively. From this experiment, expectation can be made that membrane technology can widen its applications in food and pharmaceutical industries.