Bioaccessibility of Zinc from Yogurt and Determination of Total Concentration Using Slurry Sampling and Flame Atomic Absorption Spectrometry

The bioaccessibility of Zn during in vitro gastrointestinal digestion from yogurt was investigated. In addition, the methodologies of sample preparation (dry and wet digestion, and slurry sampling) for the determination of total concentration of Zn in yogurt by flame atomic absorption spectrometry were also compared in this work. In comparison with digestion procedures, the proposed slurry sampling is simple and less time-consuming procedure. The limit of quantification determined was 1.3 µg g-1. The concentrations of Zn in the Brazilian yogurt ranged from 3.40 to 5.62 µg g-1. The percentage of the bioaccessible fraction of Zn from the samples ranged from 10 to 26%. This corresponds to an average daily intake of less than 2% of the metal for adults and children, suggesting that the Brazilian yogurt contributes with a low amount of Zn for the human diet.