title: Analysis of β-glucan molar mass from barley malt and brewer's spent grain with asymmetric flow field-flow fractionation (AF4) and their association to proteins.
abstract: β-Glucan benefits are related with its molar mass and it would be of interest to better understand how this parameter can be changed by processing and variety for design of food with specific health effects. For this purpose, extracts from barley malts and brewers' spent grain, processed at different conditions, were analysed regarding β-glucan content, molar mass, and protein content. Molar mass distribution was assessed using asymmetric flow field-flow fractionation (AF4) with multiangle light scattering (MALS), differential refractive index (dRI) and fluorescence (FL) detection. β-Glucan was detected in a wide molar mass range, <2000 to approximately 6.7×106g/mol. Differences in molar masses were more noticeable between barley varieties and steeping malting conditions than by mashing of malt. Barley products processed to preserve β-glucan contained more β-glucan of high molar mass with potential to shift the fermentation site to the distal colon. Enzymatic degradation of proteins indicated presence of aggregates containing β-glucan and protein.
authors.affiliation: Department of Food Technology, Engineering and Nutrition, Lund University, P.O. Box 124, 22100 Lund, Sweden. Electronic address: Claudia.zielke@food.lth.se.
authors.forename: Claudia
authors.initials: C
authors.lastname: Zielke
authors.affiliation: Food for Health Science Centre, Kemicentrum, Lund University, P.O. Box 124, 22100 Lund, Sweden.
authors.forename: Cristina
authors.initials: C
authors.lastname: Teixeira
authors.affiliation: Guelph Food Research Centre, Agriculture and Agri-Food Canada, Guelph, Ontario N1G 5C9, Canada.
authors.forename: Huihuang
authors.initials: H
authors.lastname: Ding
authors.affiliation: Guelph Food Research Centre, Agriculture and Agri-Food Canada, Guelph, Ontario N1G 5C9, Canada.
authors.forename: Steve
authors.initials: S
authors.lastname: Cui
authors.affiliation: Food for Health Science Centre, Kemicentrum, Lund University, P.O. Box 124, 22100 Lund, Sweden.
authors.forename: Margareta
authors.initials: M
authors.lastname: Nyman
authors.affiliation: Department of Food Technology, Engineering and Nutrition, Lund University, P.O. Box 124, 22100 Lund, Sweden.
authors.forename: Lars
authors.initials: L
authors.lastname: Nilsson
mesh_terms: D002523:Edible Grain / Q000737:chemistry; D031521:Fractionation, Field Flow; D001467:Hordeum / Q000737:chemistry*; D008970:Molecular Weight; D010940:Plant Proteins / Q000737:chemistry*; D047071:beta-Glucans / Q000737:chemistry*
chemical_list: D010940:Plant Proteins; D047071:beta-Glucans
keywords: Asymmetric flow field-flow fractionation (AF4); Calcofluor; Colonic health; Multiangle light scattering (MALS); Protein-carbohydrate complexes