“…A previous study found 80 and 90 μg/kg FA in boiled beef rib and eggs cooked for only 9 min, respectively, indicating that FA can be rapidly produced even under moderate processing conditions. FA can be produced endogenously through the bacterial oxidation of methanol, the simplest alcohol released from pectin presents in cell walls of fruit and vegetable; it is also released from methylated compounds, such as DNA, RNA, and proteins, and produced as an intermediate in the one-carbon cycle and enzymatic decomposition of trimethylamine oxide. , Thus, FA is naturally occurred in food stuffs, including fruits, vegetables, mushrooms, meats, and fish. The concentration of FA in orange, mushroom, potato tubers, hake, and opah fish were 56.9, 188, 16.5, 293, and 133.1 mg/kg, respectively. − …”