Validation of an analytical method based on QuEChERS and LC-MS/MS to quantify nine mycotoxins in plant-based milk

Abstract

Plant-based beverages (popularly known as vegetable milk) have become increasingly important in recent years. However, the nonexistence of information on mycotoxin contamination is noticeable. We herein describe the development and validation of an analytical methodology that employs QuEChERS and LC-MS/MS for the simultaneous determination of nine mycotoxins (aflatoxins B1, B2, G1, and G2, fumonisins B1 and B2, ochratoxin A, zearalenone, and citreoviridin) in seven types of vegetable milk (peanut, oat, rice, cashew, maize, soybean, and coconut). The method provided the following quantification limits, recoveries at the lowest validated concentration and relative standard deviations under repeatability conditions at the lowest validated concentration, respectively: aflatoxin B1 (0.023 μg/l, 84.98 and 9.23%); aflatoxin B2 (0.024 μg/, 93.00 and 4.85%); aflatoxin G1 (0.057 μg/l, 98.85 and 5.53%); aflatoxin G2 (0.031 μg/l, 96.64 and 4.08%); fumonisin B1 (2.166 μg/l, 75.55 and 16.78%); fumonisin B2 (1.105 μg/l, 70.47 and 11.89%); ochratoxin A (0.104 μg/l, 72.05 and 5.12%); zearalenone (8.093 μg/l, 107.10 and 6.37%); citreoviridin (1.305 μg/l, 97.25 and 7.28%). The method uses small amounts of samples, solvents, and other inexpensive reagents with no need for laborious clean-up and pre-concentration steps. Its attractive characteristics (simplicity, low cost compared to procedures that use immunoaffinity columns, and full compatibility with routine analyses) make it potentially valuable. As a proof-of-principle, the validated methodology was applied to seven commercial samples of different compositions showing that some were contaminated with aflatoxins and ochratoxin A.