title: Selenium concentration and speciation in biofortified flour and bread: Retention of selenium during grain biofortification, processing and production of Se-enriched food.
abstract: The retention and speciation of selenium in flour and bread was determined following experimental applications of selenium fertilisers to a high-yielding UK wheat crop. Flour and bread were produced using standard commercial practices. Total selenium was measured using inductively coupled plasma-mass spectrometry (ICP-MS) and the profile of selenium species in the flour and bread were determined using high performance liquid chromatography (HPLC) ICP-MS. The selenium concentration of flour ranged from 30ng/g in white flour and 35ng/g in wholemeal flour from untreated plots up to >1800ng/g in white and >2200ng/g in wholemeal flour processed from grain treated with selenium (as selenate) at the highest application rate of 100g/ha. The relationship between the amount of selenium applied to the crop and the amount of selenium in flour and bread was approximately linear, indicating minimal loss of Se during grain processing and bread production. On average, application of selenium at 10g/ha increased total selenium in white and wholemeal bread by 155 and 185ng/g, respectively, equivalent to 6.4 and 7.1μg selenium per average slice of white and wholemeal bread, respectively. Selenomethionine accounted for 65-87% of total extractable selenium species in Se-enriched flour and bread; selenocysteine, Se-methylselenocysteine selenite and selenate were also detected. Controlled agronomic biofortification of wheat crops for flour and bread production could provide an appropriate strategy to increase the intake of bioavailable selenium.
authors.affiliation: Institute of Food Research, Norwich Research Park, Colney, Norwich NR4 7UA, UK.
authors.forename: D J
authors.initials: DJ
authors.lastname: Hart
authors.affiliation: Norwich Medical School, University of East Anglia, Norwich NR4 7TJ, UK.
authors.forename: S J
authors.initials: SJ
authors.lastname: Fairweather-Tait
authors.affiliation: School of Biosciences, University of Nottingham, Sutton Bonington Campus, Loughborough, Leicestershire LE12 5RD, UK.
authors.forename: M R
authors.initials: MR
authors.lastname: Broadley
authors.affiliation: Premier Foods, Rank Hovis, Solent Mills, Western Docks, Southampton SO15 1BS, UK.
authors.forename: S J
authors.initials: SJ
authors.lastname: Dickinson
authors.affiliation: Limagrain UK Ltd., Woolpit Business Park, Windmill Avenue, Woolpit, Bury St. Edmunds, Suffolk IP30 0RA, UK.
authors.forename: I
authors.initials: I
authors.lastname: Foot
authors.affiliation: Marks and Spencer plc, Waterside House, 35 North Wharf Road, London W2 1NW, UK.
authors.forename: P
authors.initials: P
authors.lastname: Knott
authors.affiliation: Rothamsted Research, Harpenden, Hertfordshire AL5 2JQ, UK.
authors.forename: S P
authors.initials: SP
authors.lastname: McGrath
authors.affiliation: Marks and Spencer plc, Waterside House, 35 North Wharf Road, London W2 1NW, UK.
authors.forename: H
authors.initials: H
authors.lastname: Mowat
authors.affiliation: Velcourt R&D, The Stables, Red House Farm, Woodwalton, Huntingdon, Cambridgeshire PE28 5YL, UK.
authors.forename: K
authors.initials: K
authors.lastname: Norman
authors.affiliation: Carr's Fertilisers, Old Croft, Stanwix, Carlisle CA3 9BA, UK.
authors.forename: P R
authors.initials: PR
authors.lastname: Scott
authors.affiliation: Rothamsted Research, Harpenden, Hertfordshire AL5 2JQ, UK.
authors.forename: J L
authors.initials: JL
authors.lastname: Stroud
authors.affiliation: Yara (UK) Ltd., Immingham Docks, NE Lincolnshire DN4U 2NS, UK.
authors.forename: M
authors.initials: M
authors.lastname: Tucker
authors.affiliation: Scottish Crop Research Institute, Invergowrie, Dundee DD2 5DA, UK.
authors.forename: P J
authors.initials: PJ
authors.lastname: White
authors.affiliation: Rothamsted Research, Harpenden, Hertfordshire AL5 2JQ, UK.
authors.forename: F J
authors.initials: FJ
authors.lastname: Zhao
authors.affiliation: Norwich Medical School, University of East Anglia, Norwich NR4 7TJ, UK. Electronic address: R.hurst1@uea.ac.uk.
authors.forename: R
authors.initials: R
authors.lastname: Hurst
keywords: Biofortification; Bread; Flour; Selenium; Speciation; Wheat