Galacturonic Acid Recovery from Pectin Rich Agro-Wastes by Electrodialysis with Bipolar Memranes

Abstract

Pectin rich agro wastes can be utilised for manufacture of galacturonic acid. Pectin is a complex polysaccharide found in the primary cell walls and intercellular regions of higher plants. Backbone of pectin molecules is composed of galacturonic acid as a monomer. Galacturonic acid and derivates are valuable raw materials in food and cosmetic industries as acidic agents and for production of vitamin C. In this work the aim was to produce galacturonic acid from citrus pectin and sugar beet pulp. The hydrolysate of pectin contains mainly carbohydrates (oligo- and monosaccharides) and galacturonic acid. Electrodialysis with bipolar membranes (EDBM) represents an efficient technology to separate charged compounds from a solution. To remove galacturonic acid, EDBM seems a suitable process, because galacturonic acid is present as a charged compound in the solution. To obtain galacturonic acid from hydrolysate of pectin laboratory experiments were performed, similar to the system applied by Novalic et al. for recovery of other organic acids. An ED stack containing anion and cation selective and bipolar membranes was applied to obtain GA from hydrolysate.