Extraction of inulin from Beneng tuber (Xanthosoma undipes) and its application to yogurt

Abstract

Along with the increasing need for functional ingredients, research on functional polysaccharides such as inulin continous to be explored from local plants. This study aimed to develop a method to obtain a high yield of Beneng tuber's inulin by extracting inulin with varying concentrations of ethanol (30 %, 40 %, 50 %, and 96 %), determining inulin content, and elucidating the structure. Moreover, the resulting inulin was applied in yogurt making. The study found that the highest yield of inulin was obtained at 50 % ethanol concentration, by 19.641 %, with solubility at 100 °C of 32.355 %, moisture content of 8.521 %, purity of 66.205 %, and reducing sugar content of 0.698 ppm. The structure analysis by FTIR confirmed the presence of an inulin-type fructan that is the same as commercial inulin. The XRD diffractograms showed diffraction peaks characteristic of 29 % crystallinity. The inulin was applied to yogurt resulting in the highest viability of lactic acid bacteria (3.05 × 1010 CFU/mL) by adding 7 % inulin. The organoleptic properties of treatment with 7 % inulin have the best result for all parameters with pH of 4, protein 3.79 %, fat 2.31 %, water 87.06 %, carbohydrate 6.23 %, and ash 0.71 %

Keywords

• Ethanol
• Functional food
• Prebiotic
• Probiotic
• Synbiotic