Modified ganyong (Canna edulis Kerr.) starch prospective as wheat flour alternative

Abstract

Ganyong tuber (Canna edulis Kerr.) had high carbohydrate content and has potential to be used as starch. However, the starch obtained was low quality, characterized by brownish color and limited functional properties. The main aim of this work was to obtained the optimum process to transform canna starch into commercial wheat flour SNI 3751:2009 by oxidizing with food grade hydrogen peroxide (H2O2). The raw material used was white canna tuber from Samarinda, East Kalimatan which have high carbohydrate content. Initially, the starch was oxidized by 35% H2O2 food grade to form 1%, 2%, 3% concentration, slurry ratio of 10%, 20%, 30% and time of oxidation was 30, 60, 90 and 120 mins. The ganyong tuber starch was then subjected to modification process by optimizing the slurry ratio and H2O2 oxidation time. The assessment was based on basic functional properties, swelling power and water solubility. The process was conducted using a mini-propeller chamber, and data were collected in triplicates for accuracy. The optimum result was achieved with a 60-min oxidation time, 10% slurry concentration and 2% H2O2 concentration. The swelling power value reached 2.9 g/g, and water solubility was measured at 6.09 g/g. Upon proximate analysis, the canna starch contained 85.956% carbohydrates, 2.365% protein, 11.425% water and 0.254% ash content. The color analysis indicated a white degree with brightness of 91.95. Despite the improvements achieved through the process, the functional and other properties of ganyong starch were still considerably below of wheat flour standard.