Integration of physical and chemical treatment on the extraction of starch from Canna edulis. Ker. rhizome

Abstract

The extraction of Canna edulis Ker. starch from its rhizome was performed using 2 different types of press (hydraulic press and screw press) and with the addition of Na-metabisulphite and NaOH (in the range of concentration 100 - 5000 ppm each). The optimum condition for this process was determined by Central Composite. Design of experiment and the statistical calculation was solved by Design-Expert 7.0.0. The targets of the observed responses were high starch yield, low ash, low fiber, and high carbohydrate content. The results showed that the starch yield and the reduction of fiber were only influenced by the physical treatment whereas ash content in the product was influenced by both the NaOH concentration and physical treatment. The carbohydrate content in the extraction product was affected by NaOH, by the interaction between the concentrations of NaOH and Na2S2O5 and also by the physical treatment. The hydraulic press gives much better responses compared to the screw press. But in the selected range of additives concentrations, the screw press gives a higher starch yield (30% -52%).