Objective To analyze the differences in volatile organic compounds in black wheat flour, whole wheat flour and seeds in different regions of Xinjiang. Methods The volatile components of flour, whole wheat flour and seeds of 6 kinds of black wheats from 4 different regions in Xinjiang were detected using headspace gas chromatography-ion mobility spectrometry, and the volatile components were classified and feature selected using orthogonal partial least squares discriminant analysis (OPLS-DA) method. Results A total of 134 kinds of volatiles were detected in black wheat, and 97 kinds of volatile organic compounds were characterized, mainly including 23 kinds of aldehydes, 21 kinds of esters, 19 kinds of alcohols, 12 kinds of ketones and 6 kinds of acids. Relative odor activity value (ROAV) showed that 1-octen-3-one, (E)-2-octenal, 1-propanethiol, 2-formyl-5-methylthiophene, 2-methylbutyraldehyde, 4-methylbenzaldehyde, isovaleric acid, 1-oct-1-ene-3-ol and proto-guaiacol were the major volatile odorants and played a dominant role in black wheat. OPLS-DA analysis showed that there were differences between the volatiles of black wheat flour, whole wheat flour and seeds, with (E)-2-octenal mainly present in seeds, 2-methylbutyraldehyde higher in flour and 4-methylbenzaldehyde higher in whole wheat flour. Conclusion Gas chromatography-ion mobility spectrometry can be used as a technical tool to distinguish the differences in volatile compounds between different treatments of black wheat, and the results of this study provide data support for optimizing the milling process of black wheat, as well as a new direction for the identification of adulteration of black wheat whole wheat flour.
| 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 |