Comparison of oxalic acid and phosphoric acid as degumming agents for vegetable oils

For many years, phosphoric acid has been used for degumming vegetable oils with high phosphatide content prior to alkali refining. One disadvantage of this technique is the resulting undesirable phosphate waste in streams, a problem which has increased substantially in importance in recent times. We have investigated an alternative degumming technique using oxalic acid that alleviates the pollution problem in cases where water purification by means of a chemical treatment process is not possible.