Objective To study the content level of vanillin in rice and the changes of vanillin in paddy rice processing. Methods Ultra-performance liquid chromatography-tandem mass spectrometry (UPLC-MS/MS) was used to determine the contents of vanillin, methyl vanillin and ethyl vanillin in 209 batches of rice from different origins; at the same time, 16 batches of rice were hulled, milled or finished, and the rice and its processed products (brown rice, standard rice or polished rice) were tested. Results Methyl vanillin and ethyl vanillin were not detected in all rice, paddy and their processed products; vanillin was all detected in 209 batches of rice, and the content values were close to the normal distribution, mainly concentrated in ${100}\sim {222\mu}\mathrm{g}/\mathrm{{kg}}$ ; vanillin was detected in rice and its processed products (brown rice, standard rice or polished rice), and the content decreases with the processing accuracy. Conclusion The possibility of naturally occurring vanillin in rice, and the source is probably rice hull; the detection of vanillin in rice is not always illegal addition, the content level of vanillin in rice and paddy rice should be continuously studied and scientifically analyzed to provide scientific evidence for the market supervision department formulating reasonably the risk reference value of rice.
| 科 Family | 属数 Number of genus | 种数 Number of species | 占总种数比例 Percentage of total species (%) | 属 Genus | 种数 Number of species | 占总种数比例 Percentage of total species (%) |
|---|---|---|---|---|---|---|
| 鹅膏菌科Amanitaceae | 2 | 11 | 5.26 | 鹅膏菌属 Amanita | 10 | 4.78 |
| 小菇科 Mycenaceae | 2 | 12 | 5.74 | 丝盖伞属 Inocybe | 5 | 2.39 |
| 多孔菌科 Polyporaceae | 8 | 14 | 6.70 | 蜡蘑属 Laccaria | 5 | 2.39 |
| 红菇科 Russulaceae | 3 | 23 | 11.00 | 小皮伞属 Marasmius | 6 | 2.87 |
| 小菇属 Mycena | 11 | 5.26 | ||||
| 光柄菇属 Pluteus | 5 | 2.39 | ||||
| 红菇属 Russula | 17 | 8.13 | ||||
| 栓菌属 Trametes | 5 | 2.39 |