Occurrence and co-occurrence of aflatoxins, T-2, and HT-2 in instant coffee collected from China.

The natural occurrence and co-occurrence of seven mycotoxins including four aflatoxins (AFB1, AFB2, AFG1, and AFG2), two trichothecenes (T-2 and HT-2), and ochratoxin A (OTA) in 84 instant coffee samples collected from China was quantified using ultra-high performance liquid chromatography-electrospray ionization tandem mass spectrometry. It was found that 89.29 % of samples contained AFG2 toxin, with the highest and average concentrations were 13.60 μg/kg and 1.19 μg/kg. Among the other detected aflatoxins, the concentrations followed the descending order: AFG1 > AFB1 > AFB2. Notably, HT-2 and T-2 had relatively low contamination rates (9.52 % and 14.28 %, respectively); however, their maximum concentrations were high, reaching 125 μg/kg and 69.12 μg/kg, respectively. OTA were not detected in any of the samples. Significantly, 91.6 % of samples contained at least one of the six toxins, with varying patterns of co-occurrence: 52.38 % contained one toxin, 15.48 % contained two, 5.95 % contained three, 5.95 % contained four, 7.14 % contained five, and 3.57 % contained all six. A strong correlation was observed among the four aflatoxins (r = 0.76-0.58, p < 0.05), with a weaker association observed between T-2 and HT-2 (r = 0.23, p < 0.05). Moreover, significant differences were observed in the concentrations of all six toxins between samples from different latitude regions and between those with different flavors. Samples from mid-high latitude regions and black coffee samples were more likely to contain toxins at higher concentrations. These results highlighted the need for the continuous monitoring and dietary risk assessment of instant coffee consumption in China.