Analysis and evaluation of in vitro bioaccessibility of aflatoxins B1, B2, G1 and G2 in plant-based milks

Plant-based milks emerge as a healthy and vegan alternative for human diet, but these foodstuffs are susceptible to be contaminated by aflatoxins. A new method based on SPE and HPLC-MS/MS analysis was optimized and validated to test the presence of aflatoxins B1, B2, G1 and G2 analysis in almond, oat, rice and soy commercial milks. Moreover, aflatoxin bioaccessibility was evaluated through an in vitro digestion assay applied to each type of spiked milk. Aflatoxins B1, B2 and G1 were detected in one soy milk sample below the LOQ, fulfilling the limits stablished by the European Legislation. The final bioaccessibility percentages were highly dependent on the type of mycotoxin and sample matrix, the highest and the lowest values were obtained for AFB2 (82%-92%) and AFG1 (15%-30%), whereas AFB1 (28%-50%) and AFG2 (32%-76%) values resulted more influenced by the plant-based milk matrix.