title: Quinoa (Chenopodium quinoa W.) and amaranth (Amaranthus caudatus L.) provide dietary fibres high in pectic substances and xyloglucans.
abstract: Dietary fibre of quinoa and amaranth was analysed for its insoluble and soluble fibre content, composition, and structure. Total dietary fibre content was 10% for quinoa and 11% for amaranth. For both pseudocereals, 78% of its dietary fibre was insoluble. Insoluble fibre (IDF) from quinoa and amaranth was mainly composed of galacturonic acid, arabinose, galactose, xylose and glucose. Linkage analysis indicated that IDF was composed of homogalacturonans and rhamnogalacturonan-I with arabinan side-chains (∼55-60%), as well as highly branched xyloglucans (∼30%) and cellulose. For both pseudocereals, 22% of total dietary fibre was soluble; a higher proportion than that found in wheat and maize (∼15%). The soluble fibre (SDF) was composed of glucose, galacturonic acid and arabinose; for amaranth, xylose was also a major constituent. Xyloglucans made up ∼40-60% of the SDF and arabinose-rich pectic polysaccharides represented ∼34-55%.
authors.affiliation: Whistler Center for Carbohydrate Research and Department of Food Science, Purdue University, 745 Agriculture Mall Dr. West Lafayette, IN 47907, United States.
authors.forename: Lisa M
authors.initials: LM
authors.lastname: Lamothe
authors.affiliation: Nestlé Research Center, Department of Food Science and Technology, PO Box 44, Vers-chez-les-Blanc, CH-1026 Lausanne, Switzerland.
authors.forename: Sathaporn
authors.initials: S
authors.lastname: Srichuwong
authors.affiliation: Whistler Center for Carbohydrate Research and Department of Food Science, Purdue University, 745 Agriculture Mall Dr. West Lafayette, IN 47907, United States.
authors.forename: Bradley L
authors.initials: BL
authors.lastname: Reuhs
authors.affiliation: Whistler Center for Carbohydrate Research and Department of Food Science, Purdue University, 745 Agriculture Mall Dr. West Lafayette, IN 47907, United States. Electronic address: hamakerb@purdue.edu.
authors.forename: Bruce R
authors.initials: BR
authors.lastname: Hamaker
mesh_terms: D027721:Amaranthus / Q000737:chemistry*; D027465:Chenopodium quinoa / Q000737:chemistry*; D004043:Dietary Fiber / Q000032:analysis*; D005936:Glucans / Q000032:analysis*; D006603:Hexuronic Acids / Q000032:analysis; D010368:Pectins / Q000032:analysis; D011134:Polysaccharides / Q000032:analysis*; D014990:Xylans / Q000032:analysis*; D014994:Xylose / Q000032:analysis
chemical_list: D004043:Dietary Fiber; D005936:Glucans; D006603:Hexuronic Acids; D011134:Polysaccharides; D014990:Xylans; C042491:rhamnogalacturonan I; C029353:xyloglucan; C007819:galacturonic acid; D010368:Pectins; D014994:Xylose
keywords: Amaranth; Insoluble fibre; Pectic polysaccharides; Pseudocereals; Quinoa; Soluble fibre; Xyloglucans