Selenium-enriched fermented milk: A suitable dairy product to improve selenium intake in humans

The suitability of Se-enriched fermented milk as a food product for humans has been studied and sensory features, survival of microorganisms in the presence of selenium and Se bioaccessibility are presented. Sensory features and the number of colonies of microorganisms observed until the 4th week after fermentation were not affected at Se concentration levels below 2 μg g−1. To investigate bioaccessible selenium-containing compounds in selenized fermented milk, total Se was quantified after in vitro gastrointestinal digestion. Results showed that 76 ± 3% Se was extracted after gastrointestinal digestion and 24 ± 6% remained in the insoluble residue. To identify the main species of bioaccessible Se of low molecular weight (MW) generated during gastrointestinal digestion, liquid chromatography-inductively coupled plasma-mass spectrometry (LC-ICP-MS) was used. Results showed that identified selenocompounds were smaller than 1.5 kDa, with selenocystine and Se-methylselenocysteine being the most abundant compounds present in the extracts.