Table 1.
The levels of volatile components in apple juice after different sterilization methods.
| RIa | Volatile compound | Content (μg·kg−1) |
||||
|---|---|---|---|---|---|---|
| CK | CP | MS | US | HPS | ||
| Esters | ||||||
| 807 | Butyl acetate | 3.27 ± 0.98c | NDb | ND | ND | ND |
| 900 | Propyl butyrate | ND | 1.30 ± 0.01 | ND | ND | 1.47 ± 0.43 |
| 908 | Butyl propionate | 1.71 ± 0.42 | ND | ND | ND | 1.01 ± 0.23 |
| 930 | Methyl caproate | 1.09 ± 0.03 | 0.81 ± 0.10 | 0.28 ± 0.02 | 0.55 ± 0.12 | 0.73 ± 0.14 |
| 975 | Propyl-2-methyl butyrate | ND | 1.79 ± 0.40 | ND | ND | ND |
| 996 | Butyl butyrate | 28.74 ± 4.51 | 10.61 ± 0.01 | 2.55 ± 0.01 | 8.66 ± 1.63 | 9.95 ± 2.72 |
| 1003 | Ethyl hexanoate | 7.48 ± 1.45 | ND | ND | ND | ND |
| 1018 | Hexyl acetate | 3.95 ± 0.75 | 2.47 ± 0.93 | ND | 1.84 ± 0.30 | 1.98 ± 0.75 |
| 1073 | Butyl 2-methylbutanoate | 14.84 ± 2.18 | 4.17 ± 0.27 | 1.30 ± 0.03 | 4.80 ± 0.22 | 5.00 ± 1.49 |
| 1146 | Butyl-2-methyl butyrate | 5.41 ± 0.70 | ND | ND | 2.24 ± 0.31 | 2.62 ± 0.84 |
| 1166 | Pentyl-2-methyl butyrate | 2.01 ± 0.17 | 0.74 ± 0.26 | ND | 0.71 ± 0.03 | 0.84 ± 0.23 |
| 1201 | Octyl-2-methyl-propionate | 254.77 ± 3.64 | ND | ND | ND | 78.49 ± 7.35 |
| 1202 | Hexyl butyrate | ND | 44.12 ± 0.03 | 24.98 ± 0.36 | 59.21 ± 0.02 | ND |
| 1262 | Hexyl-2-methyl- butyrate | 194.65 ± 1.44 | 36.94 ± 3.81 | 34.05 ± 1.18 | 67.92 ± 0.77 | 75.87 ± 0.12 |
| 1884 | Hexyl caproate | 73.82 ± 2.99 | 15.55 ± 0.06 | 17.45 ± 1.34 | 29.84 ± 2.15 | 32.79 ± 1.50 |
| 1934 | Methyl hexadecanoate | ND | 3.65 ± 0.32 | ND | ND | ND |
| Sum | 591.75 ± 9.46 | 122.14 ± 14.26 | 80.60 ± 2.94 | 175.77 ± 9.27 | 208.27 ± 15.14 | |
| Aldehydes | ||||||
| <800 | Hexanal | 86.5 ± 2.13 | ND | ND | 24.81 ± 4.98 | ND |
| 877 | (E)-2-Hexenal, | 114.76 ± 8.69 | 74.68 ± 1.79 | 21.02 ± 0.67 | 81.32 ± 2.09 | 116.47 ± 0.74 |
| 900 | Heptanal | 11.60 ± 2.42 | ND | 2.24 ± 0.12 | ND | 2.19 ± 0.42 |
| 1002 | Octanal | ND | ND | 1.84 ± 0.16 | 2.43 ± 0.30 | 2.88 ± 0.57 |
| 1207 | Decanal | 7.73 ± 0.53 | 2.17 ± 0.55 | 1.79 ± 0.60 | 2.57 ± 0.08 | ND |
| Sum | 220.62 ± 13.76 | 76.85 ± 2.34 | 26.88 ± 1.55 | 111.13 ± 7.45 | 121.55 ± 1.74 | |
| Alcohols | ||||||
| 1002 | 1-Hexanol | 85.08 ± 1.38 | 26.89 ± 0.43 | 13.43 ± 0.99 | 33.62 ± 7.55 | 38.00 ± 0.10 |
| 1028 | 1-Heptanol | 2.19 ± 0.06 | ND | ND | ND | ND |
| 1047 | 2-Ethyl-1-hexanol | 4.15 ± 0.87 | 4.12 ± 0.24 | 4.14 ± 0.14 | 4.34 ± 0.15 | 4.72 ± 0.98 |
| 1299 | 1-Octanol | 16.45 ± 1.27 | 5.78 ± 1.49 | 1.83 ± 0.09 | 5.76 ± 0.97 | 8.06 ± 0.02 |
| Sum | 107.88 ± 3.57 | 36.79 ± 2.17 | 19.40 ± 1.22 | 43.72 ± 8.67 | 50.79 ± 1.10 | |
a
RI (retention index): Standards of n-alkanes (C8–C20) were used for RI conversion.
b
ND: Not detected.
c
Values are presented as mean ± standard deviation (P < 0.05).