Preparation of Inulin Powder from Jerusalem Artichoke (Helianthus tuberosus L.) Tuber.

The complete procedure for the production of inulin powder from Jerusalem artichoke tubers (JAT) was investigated. The procedure consists of isolation of inulin from JAT, elimination of color from the inulin extract and solidification. Washed tubers were first sliced, dried in a 60 °C oven for 10 h and then milled and sieved into a powder. Inulin was isolated from the JAT powder by hot water extraction using an accelerated solvent extractor (ASE). The effects of temperature and time for the extraction were investigated. The highest extraction efficiency was obtained at the extraction temperature of 80 °C for 20 min. The color of the extract was eliminated using ion exchange process with diethylaminoethyl cellulose as the sorbent. The inulin powder was subsequently obtained by freeze drying. Inulin content and inulin profiles were monitored to evaluate the efficiencies of the complete procedure. The inulin content was indirectly determined by spectrophotometry from free and total fructose measurements using potassium iodide. The inulin profile was monitored using high performance anion exchange chromatography equipped with integrated pulse amperometric detection (HPAEC-PAD). The proposed method provided the inulin production yield of 92.5%. The present procedure is fast, simple and effective for production of inulin powder from JAT. In addition, infrared spectra and some physico-chemical properties of the obtained inulin powder were determined and compared with the standard inulin.