title: Preparation and characterization of a laboratory scale selenomethionine-enriched bread. Selenium bioaccessibility.
abstract: This study focuses on the preparation at lab scale of selenomethionine-enriched white and wholemeal bread. Selenium was supplemented either by adding selenite directly to the dough or by using lab-made selenium-enriched yeast. The best results were obtained when using fresh selenium-enriched yeast. The optimum incubation time for selenomethionine-enriched yeast preparation, while keeping formation of selenium byproducts to a minimum, was 96 h. Selenium content measured by isotope dilution analysis (IDA)-ICP-MS in Se-white and Se-wholemeal bread was 1.28 ± 0.02 μg g–1 and 1.16 ± 0.02 μg g–1 (expressed as mean ± SE, 3 replicates), respectively. HPLC postcolumn IDA-ICP-MS measurements revealed that selenomethionine was the main Se species found in Se-enriched bread, which accounted for ca. 80% of total selenium. In vitro gastrointestinal digestion assay provided selenium bioaccessibility values of 100 ± 3% and 40 ± 1% for white and wholemeal Se-enriched bread, respectively, being selenomethionine the main bioaccessible Se species in white bread, while in wholemeal bread this compound was undetectable.
authors.forename: María
authors.initials: M
authors.lastname: Sánchez-Martínez
authors.forename: Teresa
authors.initials: T
authors.lastname: Pérez-Corona
authors.forename: Carmen
authors.initials: C
authors.lastname: Caímara
authors.forename: Yolanda
authors.initials: Y
authors.lastname: Madrid
mesh_terms: D001682:Biological Availability; D001939:Bread / Q000032:analysis*; D002851:Chromatography, High Pressure Liquid; D003296:Cooking / Q000379:methods; D005511:Food Handling / Q000379:methods; D005527:Food, Fortified / Q000032:analysis*; D006358:Hot Temperature; D013058:Mass Spectrometry; D015203:Reproducibility of Results; D012441:Saccharomyces cerevisiae; D012643:Selenium / Q000032:analysis / Q000493:pharmacokinetics*; D018036:Selenium Compounds / Q000032:analysis; D012645:Selenomethionine / Q000032:analysis*; D013030:Spain
chemical_list: D018036:Selenium Compounds; D012645:Selenomethionine; D012643:Selenium