TABLE 2.
Average contents of esters, aldehydes, alcohols, ketones, acids, nitriles, alkenes, phenols, others, and their distribution ranges (in parenthesis) in traditional fermentation Xuecai (JX), and modern fermentation Xuecai (NB).
| Codea | CAS No. | Compounds | RTb | RIc | Content of JX (μg/kg) | Content of NB (μg/kg) |
| Esters | ||||||
| E1 | 141-78-6 | Ethyl acetate | 2.14 | 621 | 36.32 (8.46–39.31) | 5.46 (0–10.24) |
| E2 | 109-60-4 | Propyl acetate | 3.71 | 708 | 20.06 (0–78.11) | 5.28 (0–9.03) |
| E3 | 623-52-7 | Methyl butyrate | 3.90 | 724 | 5.50 (0–15.53) | nd |
| E4 | 97-62-1 | Ethyl isobutyrate | 4.80 | 732 | 30.25 (0–121.00) | 5.07 (0–13.40) |
| E5 | 105-54-4 | Ethyl butyrate | 6.61 | 792 | 15.78 (0–53.69) | nd |
| E6 | 123-86-4 | Butyl acetate | 7.16 | 808 | 8.30 (0–12.86) | 2.12 (0–10.62) |
| E7 | 56601-42-4 | Cyclopropyl isothiocyanate | 9.48 | 868 | 1.51 (0–6.02) | 38.87 (0–194.35) |
| E8 | 123-92-2 | Isoamyl acetate | 9.62 | 872 | 0.47 (0–1.87) | nd |
| E9 | 057-06-7 | Allyl isothiocyanate | 9.83 | 878 | 28.68 (0–68.19) | 314.97 (26.43–1399.05) |
| E10 | 591-81-1 | 4-hydroxybutyric acid | 11.54 | 923 | 0.34 (0–1.35) | 1.84 (0–9.18) |
| E11 | 592-82-5 | Butyl isothiocyanate | 11.60 | 925 | nd | 6.70 (0–33.50) |
| E12 | 591-82-2 | Isobutyl isothiocyanate | 12.40 | 947 | nd | 3.34 (0–16.68) |
| E13 | 10348-47-7 | Ethyl 2-hydroxy-4-methylvalerate | 16.16 | 1055 | 6.04 (0–16.62) | 5.18 (0–9.91) |
| E14 | 108-84-9 | 1,3-dimethylbutyl acetate | 19.25 | 1162 | 93.43 (41.73–149.89) | 39.63 (29.37–46.99) |
| E15 | 103-45-7 | Phenethyl acetate | 22.21 | 1252 | 0.96 (0–3.85) | 1.48 (0–5.89) |
| E16 | 628-97-7 | Palmitic acid ethyl ester | 38.82 | 1987 | 0.44 (0–1.75) | 0.74 (0–2.75) |
| Aldehydes | ||||||
| L1 | 110-62-3 | Valeraldehyde | 3.26 | 696 | 6.18 (1.72–9.71) | 2.08 (0–5.83) |
| L2 | 66-25-1 | Hexanal | 6.44 | 787 | nd | 1.83 (0–6.77) |
| L3 | 098-01-1 | Furfural | 7.66 | 821 | 6.06 (0–24.25) | 1.14 (0–5.72) |
| L4 | 3268-49-3 | 3-(methylthio)propionaldehyde | 10.65 | 899 | 0.32 (0–1.28) | 1.10 (0–3.42) |
| L5 | 100-52-7 | Benzaldehyde | 12.65 | 954 | 49.80 (22.59–122.25) | 38.97 (22.21–50.56) |
| L6 | 122-78-1 | Phenylacetaldehyde | 15.60 | 1038 | 15.42 (7.16–33.01) | 7.21 (0–14.53) |
| L7 | 124-19-6 | 1-nonanal | 17.63 | 1099 | 0.74 (0–2.955) | 0.73 (0–3.65) |
| L8 | 5779-94-2 | 2,5-dimethylbenzaldehyde | 21.00 | 1210 | 0.82 (0–3.26) | 0.64 (0–3.18) |
| L9 | 432-25-7 | β-cyclocitral | 21.18 | 1216 | 0.42 (0–1.68) | 1.91 (0–5.82) |
| L10 | 4411-89-6 | 2-phenyl-2-butenal | 22.66 | 1268 | 4.74 (0–18.96) | 3.64 (0–18.19) |
| L11 | 4951-40-0 | 3-(2,6,6-trimethyl-1-cyclohexen-1-yl) acrylaldehyde | 26.09 | 1395 | 24.22 (13.86–41.29) | 3.81 (0–14.25) |
| Alcohols | ||||||
| A1 | 64-17-5 | Ethanol | 1.40 | 482 | 65.00 (26.43–116.62) | 24.40 (12.95–42.08) |
| A2 | 71-23-8 | 1-propanol | 1.77 | 547 | 0.84 (0–3.36) | nd |
| A3 | 78-92-2 | 2-butanol | 2.04 | 597 | 0.49 (0–1.96) | nd |
| A4 | 71-36-3 | 1-butanol | 2.79 | 657 | 89.55 (0–129.25) | nd |
| A5 | 123-51-3 | 3-methyl-1-butano | 4.31 | 716 | 3.35 (0–8.22) | 2.08 (0–10.39) |
| A6 | 71-41-0 | 1-pentanol | 5.40 | 752 | 13.37 (0–30.53) | 1.37 (0–3.52) |
| A7 | 1576-95-0 | Cis-2-penten-1-ol | 5.50 | 755 | nd | 11.85 (0–24.88) |
| A8 | 565-60-6 | 3-methyl-2-pentanol | 5.84 | 767 | nd | 0.85 (0–4.27) |
| A9 | 544-12-7 | Trans-3-hexen-1-ol | 8.69 | 848 | nd | 0.89 (0–4.46) |
| A10 | 928-96-1 | Cis-3-hexen-1-ol | 8.75 | 850 | nd | 13.51 (0–45.10) |
| A11 | 98-00-0 | Furfuryl alcohol | 9.06 | 858 | nd | 1.30 (0–6.52) |
| A12 | 111-27-3 | 1-hexanol | 9.43 | 867 | 8.93 (0–17.24) | nd |
| A13 | 505-10-2 | 3-methylthiopropanol | 13.47 | 976 | nd | 1.13 (0–4.30) |
| A14 | 104-76-7 | 2-ethylhexanol | 15.22 | 1026 | 1.85 (0–7.40) | 0.86 (0–4.31) |
| A15 | 98-85-1 | Dl-1-phenethylalcohol | 16.32 | 1060 | 17.66 (6.83–44.34) | 1.18 (6.63–20.54) |
| A16 | 5337-72-4 | 2,6-dimethylcyclohexanol | 17.71 | 1102 | nd | 1.21 (0–6.05) |
| A17 | 060-12-8 | Phenethyl alcohol | 18.00 | 1112 | 113.09 (57.01–245.17) | 77.97 (56.19–100.38) |
| A18 | 122-97-4 | 3-phenyl-1-propanol | 21.50 | 1227 | 14.70 (0–58.79) | nd |
| Ketones | ||||||
| K1 | 1629-58-9 | Ethyl vinyl ketone | 3.04 | 678 | nd | 6.83 (0–14.67) |
| K2 | NA | Oxime-, methoxy-phenyl | 11.89 | 933 | 20.98 (0–56.97) | nd |
| K3 | 110-93-1 | 6-methyl-5-hepten-2-one | 13.72 | 983 | 1.14 (0–4.54) | 2.07 (0–6.78) |
| K4 | 3879-26-3 | Nerylacetone | 27.39 | 1446 | 0.23 (0–0.91) | nd |
| K5 | 79-77-6 | β-lonone | 28.28 | 1481 | 0.28 (0–1.13) | 7.11 (0–14.80) |
| K6 | 532-65-0 | Ar-turmerone | 33.53 | 1663 | 24.11 (0–80.35) | nd |
| K7 | 180315-67-7 | Tumerone | 33.63 | 1666 | 8.06 (0–27.21) | nd |
| K8 | 87440-60-6 | Curlone | 34.38 | 1696 | 6.50 (0–21.49) | nd |
| Acids | ||||||
| C1 | 124-07-2 | Octanoic acid | 20.19 | 1183 | 1.12 (0–4.49) | 1.18 (0–5.88) |
| C2 | 142-62-1 | Hexanoic acid | 14.51 | 1005 | 7.35 (2.32–9.39) | 17.96 (3.20–29.47) |
| Nitriles | ||||||
| N1 | 109-75-1 | 3-butenenitrile | 2.67 | 658 | 59.53 (8.61–2155.92) | 109.27 (45.31–210.63) |
| N2 | 140-29-4 | Benzeneacetonitrile | 18.71 | 1135 | nd | 0.75 (0–3.76) |
| N3 | 645-59-0 | 3-phenylpropionitrile | 21.76 | 1237 | 234.41 (0–636.58) | 172.53 (79.83–295.47) |
| Alkenes | ||||||
| AL1 | 26456-76-8 | 3,5,5-trimethyl-2-hexene | 13.28 | 971 | nd | 1.81 (0–5.18) |
| AL2 | 644-30-4 | α-curcumene | 28.20 | 1477 | 65.81 (0–222.89) | nd |
| AL3 | 495-60-3 | α-zingiberene | 28.50 | 1489 | 20.99 (0–67.92) | nd |
| AL4 | 495-61-4 | β-bisabolene | 28.87 | 1503 | 11.62 (0–35.75) | nd |
| AL5 | 20307-83-9 | β-sesquiphellandrene | 29.29 | 1516 | 35.10 (0–120.69) | nd |
| Phenols | ||||||
| P1 | 108-95-2 | Phenol | 14.00 | 990 | 39.21 (0–86.97) | 3.30 (0–16.48) |
| P2 | 106-44-5 | 4-hydroxytoluene | 17.06 | 1082 | 205.41 (4.90–744.13) | 7.55 (0–25.34) |
| P3 | 123-07-9 | 4-ethylphenol | 19.79 | 1170 | 20.85 (0–69.97) | 14.62 (0–44.26) |
| P4 | 1195-09-1 | 2-methoxy-5-methylphenol | 20.38 | 1189 | 0.43 (0–1.73) | 0.48 (0–2.41) |
| P5 | 2785-89-9 | 4-ethyl-2-methoxyphenol | 22.85 | 1275 | 12.95 (0–42.96) | 13.51 (0–36.36) |
| P6 | 7786-61-0 | 4-hydroxy-3-methoxystyrene | 23.81 | 1310 | 22.52 (17.81–46.83) | 22.06 (5.63–34.50) |
| P7 | 96-76-4 | 2,4-di-tert-butylphenol | 28.99 | 1507 | 0.96 (0–3.84) | 1.53 (0–3.96) |
| Others | ||||||
| O1 | 624-92-0 | Dimethyl disulfide | 4.20 | 712 | nd | 7.19 (0–24.91) |
| O2 | 106-42-3 | P-xylene | 9.13 | 860 | 0.35 (0–1.38) | 0.75 (0–3.76) |
| O3 | 111-76-2 | 2-Butoxyethanol | 10.75 | 902 | 0.05 (0–0.18) | 5.68 (0–17.09) |
| O4 | 3658-80-8 | Dimethyl trisulfide | 14.12 | 993 | nd | 3.95 (0–19.77) |
| O5 | 3238-55-9 | 2-Propionylpyridine | 18.25 | 1120 | nd | 2.43 (0–12.15) |
| O6 | 496-16-2 | 2,3-Dihydrobenzofuran | 21.39 | 1224 | 14.59 (0–58.37) | 9.03 (0–30.29) |
| O7 | 1014-60-4 | 1,3-di-tert-butylbenzene | 22.09 | 1248 | 1.42 (0–5.67) | 5.34 (0–14.04) |
aCompound codes. bRetention time (min). cRetention index. nd, not detected; NA, not applicable.