Cassava starch maltodextrinization/monomerization through thermopressurized aqueous phosphoric acid hydrolysis

Kinetic conditions were established for the depolymerization of cassava sta rch for the production of maltodextrins and glucose syrups. Thin-layer chro matography and high-performance liquid chromatography analyses corroborated that the proper H,PO, strength and thermopressurization range (e.g., 142-1 70 degreesC; 2.8-6.8 atm) can be successfully explored for such hydrolytic purposes of native starch granules. Because phosphoric acid can be advantag eously maintained in the hydrolysate and generates, after controlled neutra lization with ammonia, the strategic nutrient triplet for industrial fermen tations (C, P, N), this pretreatment strategy can be easily recognized as a recommended technology for hydrolysis and upgrading of starch and other pl ant polysaccharides. Compared to the classic catalysts, the mandatory desal ting step (chloride removal by expensive anion-exchange resin or sulfate pr ecipitation as the calcium-insoluble salt) can be avoided. Furthermore, pro perly diluted phosphoric acid is well known as an allowable additive in sev eral popular soft drinks such as colas since its acidic feeling in the mout h is compatible and synergistic with both natural and artificial sweeteners . Glycosyrups from phosphorolyzed cassava starch have also been upgraded to high-value single-cell protein such as the pigmented yeast biomass of Xant hophyllomyces dendrorhous (Phaffia rhodozyma), whose astaxanthin (wiketo-di hydroxy-beta -carotene) content may reach 0.5-1.0 mg/g of dry yeast call. T his can he used as an ideal complement for animal feeding as well as a natu ral staining for both fish farming (meat) and poultry (eggs).