Characterization and estimation of the bioaccessibility of essential elements in organic milk by INFOGEST protocol

The study estimated the bioaccessibility of calcium, phosphorus and magnesium in organic milk (ORG), compared to conventional (CNV) by the INFOGEST in vitro protocol. Total proteins, lipids and lactose were evaluated, the determination of essential minerals was performed by FAAS and phosphorus by colorimetric method. All ORG samples showed protein content equivalent to CNV and lower lactose and lipid content. Within different brands and batches, two batches of ORG presented higher levels of Na and lower levels of K and P, while all batches showed higher values for Ca and no differences for Mg. The bioaccessibility of magnesium was greater than 60%. ORG showed the highest values of bioaccessible calcium (12-65%) against CNV (11-27%). Phosphorus showed bioaccessibility higher than 74% in CNV. The variability of the results was related to different factors inherent to the matrices, such as casein and fatty-acids content and electrolytes standardized in the protocol.