The physiochemical properties and dietary fiber content of Chenopodium formosanum

• Main Authors: Liang,Chiao-Ling, 梁喬菱
• Other Authors: Liu, Chan-Chiung
• Format: Others
• Language: zh-TW
• Published: 2016
• Online Access: http://ndltd.ncl.edu.tw/handle/76975422113219907842

碩士 === 國立屏東科技大學 === 食品科學系所 === 104 === Djulis (Chenopodium formosanum), due to its high nutritional values (abundant protein, fat, dietary fiber, carbohydrate, and minerals), has been one of the important cereal crops for Taiwan aborigines, and receives increasing attention. Similar to quinoa (Chenopodium quinoa), Djulis is believed to have functional characteristics and health benefits primarily attributed to its ample dietary fiber. Dietary fiber is a plant ingredient, which cannot be digested by the stomach enzymes. Dietary fiber (DF) could be classified into soluble dietary fiber (SDF) and insoluble dietary fiber (IDF) depending on their solubility in water. This thesis investigated the compositions, physicochemical properties in cereal’s SDF and IDF, respectively, for Djulis, along with oat (Avena sativa, from Australia), and Antigua Mainz quinoa (Chenopodium quinoa W.). The physicochemical properties of fiber types including bulk density, water holding capacity, oil-holding capacity, swelling property. The results showed that total dietary fiber content for whole Djulis is 17.24%, compared to 13.36% for dehulled Djulis, 12.71% for oat, and 10.83% for Antigua Mainz quinoa. SDF constitutes 24.25% and 23.65% of total dietary fiber in whole Djulis and dehulled Djulis, which is significantly higher than 20.85% in oat, and 19.66% in quinoa. SDF and IDF from dehulled Djulis was mainly composed of xylose (46.7 %, 31.51 %). Dehulled Djulis have a number of hemicellulose which was composed of xylan, and a small amount of pectin substances composed of rhamnose, galactose, xylose, etc. As to the physicochemical characteristics, IDF of Djulis exhibited better water-holding capacity (3.12-3.73 mL/g), oil-holding capacity (4.03-5.17 mL/g), and swelling property (4.03-5.17 mL/g) than oat and quinoa. Djulis cation-exchange capacity (417-624meq / kg), which is higher than oat (77 meq / kg) but similar with the quinoa (514 meq / kg), cation-exchange capacity is related to uronic acid and lignin contents from IDF, and it can eliminate the highly toxic metal cations from the human body. In the part of cholic acid binding capacity, the results showed that the dietary fiber of Djulis has cholic acid binding capacity, and the binding capacity of IDF (37.86-41.30%) is better than SDF (16.78-25.84%), this related to cation-exchange capacity and the lignin contents of the IDF. The results of in vitro digestibility suggested that Djulis contains less rapidly digestible starch (RDS) and higher slowly digestible starch (SDS), which could inhibit postprandial elevated blood glucose level and hyperinsulinemia. In conclusion, Djulis provides large amounts of dietary fiber, it has good physiochemical properties and physiological activities. In addition to improve the texture of food, it may also has health-promoting function for human intestinal. This finding could further be applied to the development and promotion of related health products based on Djulis.