Quinoa (Chenopodium quinoa W.) and amaranth (Amaranthus caudatus L.) provide dietary fibres high in pectic substances and xyloglucans. (15th January 2015)

• Record Type: Journal Article
• Authors: Lamothe, Lisa M.; Srichuwong, Sathaporn; Reuhs, Bradley L.; Hamaker, Bruce R.
• Is Part Of: Food chemistry. Volume 167(2015)
• Page Start: 490
• Page End: 496
• Publication Date: 2015-01-15
• Subjects: Pseudocereals -- Quinoa -- Amaranth -- Insoluble fibre -- Soluble fibre -- Pectic polysaccharides -- Xyloglucans; Food -- Analysis -- Periodicals; Food -- Composition -- Periodicals; 664
• DOI: 10.1016/j.foodchem.2014.07.022
• Languages: English
• ISSNs: 0308-8146

Abstract

Highlights: Dietary fibre from quinoa and amaranth was quantified and partially characterised. Total dietary fibre of each was 78% insoluble and 22% soluble fibre. Insoluble fibre from the pseudocereals was mainly composed of pectic substances. Xyloglucans were the main polysaccharide in soluble fibre from pseudocereals. Quinoa and amaranth fibre composition is similar to vegetables and leguminous seeds. 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%.