The purpose of this study was to analyze the volatile compounds in baby ginger paocai and the fresh baby ginger and identify the key aroma components that contribute to the flavor of baby ginger paocai. A total of 86 volatile compounds from the two baby ginger samples were quantified; these compounds were extracted by headspace solid-phase microextraction (HS-SPME) and analyzed by gas chromatography–mass spectrometry (GC-MS). The aroma composition of baby ginger paocai was different from that of fresh baby ginger. Baby ginger paocai was characterized by the presence of aroma-active compounds which varied in concentration from 0.03 to 28.14%. Geranyl acetate was the aroma component with the highest relative content in baby ginger paocai.
Baby ginger, which is a kind of ginger rhizomes
Ginger paocai, as a Chinese pickle, has been consumed by the people of Sichuan province in China for a long time [
In quality indices, aroma is one of the most appreciated characteristics that confirm the initial impression of consumers. Recently, there were many researches on the aroma composition of food, and the experts in these studies believed that the flavor of food was different with its type. Furthermore, some volatile compounds of some food products are not detected by consumers because of their thresholds and interactions with other compounds [
Baby ginger paocai was sampled from Yingu Food Inc. located in Chengdu, China. The baby ginger paocai was produced according to the processing method and the particular steps described in subsequent content. Firstly, the selected fresh baby ginger samples were washed in water jet washer and then drained. After being cut, 8 kilograms of fresh baby ginger was put into one of the 25-litre pottery jars which were washed, sterilized, and cooled in advance. Before the baby ginger samples were put into the jar, the jar had 16 litres of 4% saline water, so that the baby ginger paocai was slightly salted. Then 60 grams of bacterial powder, as a starter culture for the baby ginger fermentation, was added to the jar. There were 1.5 × 1010 cfu active lactic acid bacteria in each gram of the bacterial powder. Finally, the jars were sealed and placed in a room where the temperature was
On the 7th day of the baby ginger fermentation, the baby ginger paocai was sampled and stored in a refrigerator at 4°C. The fresh baby ginger was also sampled from this food company and stored in a freezer at 4°C prior to analysis, in order to compare its flavor formation with that of baby ginger paocai. The fresh baby ginger, as the raw material for baby ginger paocai, was of good quality and short of serious mechanical damage. The collected baby ginger samples were of similar length (about
A mixture of
Researchers usually cut and crush the samples for aroma analysis, so that the aroma substances are extracted completely. In order to exhibit the overall flavor of the baby ginger samples, every sample was sliced, chopped, and mixed together. And then, using the random sampling method, 5 g of the chops mixture was obtained and put in a headspace bottle. All parameters were analyzed and determined at least in triplicate at each sampling time.
After comparing the extraction characteristics of several kinds of SPME fibers (such as PDMS, PDMS/DVB, Carboxen/PDMS, and DVB/CAR/PDMS), the authors selected a stableflex 50/30
The optimum sampling conditions of aroma compounds in baby ginger samples with the DVB/CAR/PDMS fiber were investigated. Before the aroma components were extracted by the fiber, there was a partition equilibrium of the aroma components between the crushed baby ginger and the headspace of the bottle. The process of the equilibrium of aroma components was conditioned at 45°C for 30 min. And then the DVB/CAR/PDMS fiber was exposed to the headspace for 30 min at 45°C so that the fiber could enrich aroma components completely.
The volatile compounds of baby ginger were identified by the method of gas chromatography–mass spectrometry (GC-MS). The gas chromatograph, whose model was Agilent 7890A, was equipped with a HP-5MS capillary column (30 m × 0.25 mm × 0.25
The mass spectra of the volatile compounds of baby ginger were compared with the data system library (NIST 11) and authentic references [
GC-O analysis was performed on a GC equipped with a PHASER olfactory port (GL Sciences, Inc., Tokyo, Japan) and a HP-5MS capillary column (30 m × 0.25 mm × 0.25
After being concentrated by the SPME fiber on the optimal extraction conditions, the volatile compounds of baby ginger samples were separated and detected under the before-mentioned GC-MS conditions. The total ion current (TIC) chromatogram for the aromatic compounds of each baby ginger sample was obtained by GC-MS.
According to the results of qualitative analysis, there were 86 volatile compounds identified in the two baby ginger samples. The results of GC-MS analysis were listed in Table
The volatile compounds of the two baby ginger samples by GC-MS analysis.
Number | Compounds | RI |
CAS# | Baby ginger paocai |
Fresh baby ginger | Chemical |
Differences between the two samples |
|||
---|---|---|---|---|---|---|---|---|---|---|
AC (mg/kg) | RC (%) | AC (mg/kg) | RC (%) | |||||||
(1) | (−)- |
944 | 007785-26-4 | 6.901 ± 6.347 | 0.74 | 9.921 ± 7.189 | 0.49 | Olefine | MH |
|
(2) | Camphene | 958 | 000079-92-5 | 18.213 ± 15.496 | 1.95 | 22.929 ± 14.985 | 1.14 | Olefine | MH |
|
(3) |
|
985 | 000127-91-3 | 2.646 ± 1.769 | 0.28 | 5.069 ± 1.242 | 0.25 | Olefine | MH |
|
(4) |
|
1001 | 000123-35-3 | 34.840 ± 12.080 | 3.74 | 35.733 ± 14.751 | 1.78 | Olefine | MH |
|
(5) |
|
1013 | 000099-83-2 | 3.592 ± 1.934 | 0.39 | 10.169 ± 2.447 | 0.51 | Olefine | MH |
|
(6) |
|
1023 | 000099-86-5 | 0.967 ± 0.052 | 0.1 | 1.137 ± 0.672 | 0.06 | Olefine | MH |
|
(7) | 2-Carene | 1024 | 000554-61-0 | 1.734 ± 0.154 | 0.19 | 2.169 ± 0.391 | 0.11 | Olefine | SH |
|
(8) | Eucalyptol | 1035 | 000470-82-6 | 26.255 ± 0.867 | 2.82 | 8.365 ± 6.259 | 0.42 | Alcohol | OCM |
|
(9) | trans- |
1044 | 003779-61-1 | 8.355 ± 3.512 | 0.9 | 11.688 ± 5.252 | 0.58 | Olefine | MH |
|
(10) | Z-Ocimene | 1054 | 003338-55-4 | 11.267 ± 2.565 | 1.21 | 15.886 ± 5.012 | 0.79 | Olefine | MH |
|
(11) |
|
1063 | 000099-85-4 | 1.388 ± 1.228 | 0.15 | 1.411 ± 1.003 | 0.07 | Olefine | MH |
|
(12) | Terpinolene | 1092 | 000586-62-9 | 5.555 ± 4.713 | 0.6 | 10.240 ± 6.364 | 0.51 | Olefine | MH |
|
(13) | Linalool | 1105 | 000078-70-6 | 6.344 ± 2.529 | 0.68 | 11.312 ± 0.428 | 0.56 | Alcohol | OCM |
|
(14) | (4E,6Z)-allo-Ocimene | 1132 | 007216-56-0 | 1.884 ± 0.870 | 0.2 | 3.058 ± 1.202 | 0.15 | Olefine | MH |
|
(15) | (−)-Terpinen-4-ol | 1181 | 020126-76-5 | 2.994 ± 0.597 | 0.32 | 3.499 ± 0.230 | 0.17 | Alcohol | OCM |
|
(16) | Cryptone | 1189 | 000500-02-7 | 2.497 ± 0.857 | 0.27 | nd | Ketone | Other | ||
(17) |
|
1196 | 000098-55-5 | 6.271 ± 0.738 | 0.67 | 10.614 ± 0.382 | 0.53 | Alcohol | OCM |
|
(18) | Decanal | 1205 | 000112-31-2 | 1.226 ± 0.566 | 0.13 | nd | Aldehyde | Other | ||
(19) | Acetic acid, octyl ester | 1210 | 000112-14-1 | 4.347 ± 1.325 | 0.47 | 1.175 ± 0.201 | 0.06 | Ester | Other |
|
(20) | cis-citral | 1238 | 000106-26-3 | 45.425 ± 2.278 | 4.87 | 14.314 ± 7.268 | 0.71 | Aldehyde | OCM |
|
(21) | Geraniol | 1260 | 000106-24-1 | 76.354 ± 23.820 | 8.19 | 116.402 ± 4.987 | 5.78 | Alcohol | OCM |
|
(22) | trans-citral | 1271 | 000141-27-5 | 78.771 ± 2.787 | 8.45 | 67.512 ± 1.272 | 3.35 | Aldehyde | OCM |
|
(23) | Bornyl acetate | 1283 | 000076-49-3 | 7.327 ± 1.229 | 0.79 | 7.855 ± 1.270 | 0.39 | Ester | OCM |
|
(24) | 2-Undecanone | 1292 | 000112-12-9 | 1.363 ± 0.315 | 0.15 | 1.121 ± 0.187 | 0.06 | Ketone | Other |
|
(25) | Methyl geranate | 1321 | 002349-14-6 | 4.187 ± 0.854 | 0.45 | 1.108 ± 0.191 | 0.06 | Ester | OCM |
|
(26) |
|
1342 | 017699-14-8 | 1.421 ± 0.479 | 0.15 | 2.057 ± 1.659 | 0.1 | Olefine | SH |
|
(27) | 2,6-Octadiene,2,6-dimethyl- | 1349 | 002792-39-4 | 20.255 ± 7.063 | 2.17 | 20.745 ± 10.698 | 1.03 | Olefine | MH |
|
(28) | (+)-Cyclosativene | 1356 | 022469-52-9 | 1.868 ± 1.426 | 0.2 | 2.745 ± 1.409 | 0.14 | Olefine | SH |
|
(29) | Neryl acetate | 1360 | 000141-12-8 | 4.522 ± 1.680 | 0.49 | 4.640 ± 2.745 | 0.23 | Ester | OCM |
|
(30) | .alfa.-Copaene | 1367 | 1000360-33-0 | 5.442 ± 4.577 | 0.58 | 9.635 ± 6.294 | 0.48 | Olefine | MH |
|
(31) | Geranyl acetate | 1387 | 000105-87-3 | 262.248 ± 69.539 | 28.14 | 122.273 ± 20.639 | 6.07 | Ester | OCM |
|
(32) | 3-Decen-1-ol, acetate, (Z)- | 1393 | 081634-99-3 | 1.815 ± 0.419 | 0.19 | nd | Ester | Other | ||
(33) | Ethyl geranate | 1395 | 032659-21-5 | 2.039 ± 0.106 | 0.22 | nd | Ester | OCM | ||
(34) | 2,6-Octadienoic acid, 3,7-dimethyl-, ethyl ester | 1397 | 013058-12-3 | 1.633 ± 0.788 | 0.18 | nd | Ester | OCM | ||
(35) | (E)-2-Decenyl acetate | 1407 | 002497-23-6 | 1.680 ± 0.480 | 0.18 | nd | Ester | Other | ||
(36) | Caryophyllene | 1411 | 000087-44-5 | 3.419 ± 1.501 | 0.37 | 4.197 ± 1.024 | 0.21 | Olefine | SH |
|
(37) |
|
1420 | 013744-15-5 | 1.402 ± 0.299 | 0.15 | 2.332 ± 2.083 | 0.12 | Olefine | SH |
|
(38) |
|
1426 | 029873-99-2 | 1.021 ± 0.823 | 0.11 | 15.977 ± 5.546 | 0.79 | Olefine | SH |
|
(39) |
|
1427 | 017699-05-7 | 1.963 ± 1.241 | 0.21 | 2.366 ± 0.565 | 0.12 | Olefine | SH |
|
(40) |
|
1439 | 000489-40-7 | 7.720 ± 4.677 | 0.83 | 18.825 ± 2.127 | 0.94 | Olefine | SH |
|
(41) | Humulene | 1442 | 006753-98-6 | 0.934 ± 0.123 | 0.1 | 1.261 ± 1.218 | 0.06 | Olefine | SH |
|
(42) | Alloaromadendrene | 1449 | 025246-27-9 | 10.019 ± 6.700 | 1.08 | 15.264 ± 10.124 | 0.76 | Olefine | SH |
|
(43) |
|
1467 | 030021-74-0 | 4.231 ± 1.549 | 0.45 | 12.588 ± 4.930 | 0.63 | Olefine | SH |
|
(44) | Curcumene | 1478 | 000644-30-4 | 58.679 ± 28.671 | 6.3 | 60.331 ± 38.828 | 3 | Olefine | SH |
|
(45) |
|
1482 | 017066-67-0 | 10.802 ± 1.776 | 1.16 | 15.428 ± 10.440 | 0.77 | Olefine | SH |
|
(46) |
|
1488 | 039029-41-9 | 24.059 ± 11.612 | 2.58 | 31.411 ± 5.120 | 1.56 | Olefine | SH |
|
(47) |
|
1491 | 031983-22-9 | 5.260 ± 1.698 | 0.56 | 6.361 ± 0.895 | 0.32 | Olefine | SH |
|
(48) |
|
1503 | 000483-76-1 | 2.414 ± 0.797 | 0.26 | 2.632 ± 0.060 | 0.13 | Olefine | SH |
|
(49) |
|
1505 | 000495-61-4 | 99.141 ± 43.066 | 10.64 | 106.968 ± 24.872 | 5.31 | Olefine | SH |
|
(50) |
|
1520 | 020307-83-9 | 27.614 ± 0.862 | 2.96 | 150.857 ± 60.224 | 7.49 | Olefine | SH |
|
(51) |
|
1534 | 021391-99-1 | 0.597 ± 0.180 | 0.06 | 0.658 ± 0.463 | 0.03 | Olefine | SH |
|
(52) | Sesqui rosefuran | 1548 | 039007-93-7 | 0.260 ± 0.128 | 0.03 | nd | Furan | OCS | ||
(53) | (E)-Nerolidol | 1560 | 040716-66-3 | 4.120 ± 1.205 | 0.44 | 4.401 ± 1.579 | 0.22 | Alcohol | OCS |
|
(54) | .gamma.-Eudesmol | 1608 | 1000374-18-5 | 0.614 ± 0.138 | 0.07 | 0.939 ± 0.433 | 0.05 | Alcohol | OCM |
|
(55) | Eudesma-4(14)-en-11-ol | 1645 | 000473-15-4 | 0.586 ± 0.294 | 0.06 | 1.596 ± 1.537 | 0.08 | Alcohol | OCS |
|
(56) | 4-(1,5-Dimethylhex-4-enyl)cyclohex-2-enone | 1689 | 001723-80-4 | 2.140 ± 1.864 | 0.23 | nd | Ketone | Other | ||
(57) | Farnesol, acetate | 1845 | 1000352-67-2 | 0.773 ± 0.244 | 0.08 | 0.284 ± 0.142 | 0.01 | Ester | OCS |
|
(58) | (E,E)-Farnesyl acetate | 1847 | 004128-17-0 | 0.427 ± 0.170 | 0.05 | 2.261 ± 0.089 | 0.11 | Ester | OCS |
|
(59) | (+)-4-Carene | 1025 | 029050-33-7 | nd | 2.936 ± 2.493 | 0.15 | Olefine | SH | ||
(60) |
|
1037 | 000555-10-2 | nd | 131.863 ± 20.984 | 6.55 | Olefine | SH | ||
(61) | Cyclopropane, pentyl- | 1083 | 002511-91-3 | nd | 1.414 ± 0.781 | 0.07 | Alkane | Other | ||
(62) | 1-Octanol | 1084 | 000111-87-5 | nd | 0.610 ± 0.143 | 0.03 | Alcohol | Other | ||
(63) | Cycloheptane, 1,3,5-tris(methylene)- | 1138 | 068284-24-2 | nd | 0.395 ± 0.159 | 0.02 | Olefine | SH | ||
(64) | Borneol | 1176 | 000507-70-0 | nd | 3.344 ± 0.873 | 0.17 | Alcohol | OCM | ||
(65) | Citronellol | 1232 | 000106-22-9 | nd | 32.434 ± 11.441 | 1.61 | Alcohol | OCM | ||
(66) | Geranyl formate | 1301 | 000105-86-2 | nd | 0.241 ± 0.101 | 0.01 | Ester | OCM | ||
(67) | 2,6-Octadien-1-ol, 3,7-dimethyl-, acetate | 1317 | 016409-44-2 | nd | 0.909 ± 0.256 | 0.05 | Ester | OCM | ||
(68) |
|
1331 | 020307-84-0 | nd | 5.823 ± 4.249 | 0.29 | Olefine | SH | ||
(69) | Ylangene | 1363 | 014912-44-8 | nd | 2.941 ± 2.435 | 0.15 | Olefine | SH | ||
(70) |
|
1389 | 000515-13-9 | nd | 11.249 ± 1.930 | 0.56 | Olefine | SH | ||
(71) | .beta.-Ylangene | 1413 | 1000374-19-1 | nd | 1.857 ± 1.288 | 0.09 | Olefine | SH | ||
(72) | cis- |
1451 | 028973-97-9 | nd | 10.735 ± 1.951 | 0.53 | Olefine | SH | ||
(73) | beta.-Curcumene | 1457 | 1000374-17-4 | nd | 4.085 ± 2.934 | 0.2 | Olefine | SH | ||
(74) | cis-Muurola-3,5-diene | 1464 | 1000365-95-4 | nd | 5.732 ± 0.505 | 0.28 | Olefine | SH | ||
(75) |
|
1474 | 001461-03-6 | nd | 196.378 ± 89.595 | 9.76 | Olefine | SH | ||
(76) | Zingiberene | 1496 | 000495-60-3 | nd | 378.829 ± 155.018 | 18.82 | Olefine | SH | ||
(77) |
|
1510 | 000502-61-4 | nd | 213.335 ± 104.636 | 10.6 | Olefine | SH | ||
(78) | Naphthalene, 1,2,4a,5,6,8a-hexahydro-4,7-dimethyl-1-(1-methylethyl)-,[1R-(1.alpha.,4a.alpha.,8a.alpha.)]- | 1529 | 017627-24-6 | nd | 2.708 ± 0.948 | 0.13 | Olefine | SH | ||
(79) | Selina-3,7(11)-diene | 1532 | 006813-21-4 | nd | 1.738 ± 1.245 | 0.09 | Olefine | SH | ||
(80) | Elemol | 1543 | 000639-99-6 | nd | 3.891 ± 2.029 | 0.19 | Alcohol | OCS | ||
(81) |
|
1551 | 000560-32-7 | nd | 1.124 ± 0.818 | 0.06 | Olefine | SH | ||
(82) | 1R,4S,7S,11R-2,2,4,8-Tetramethyltricyclo[5.3.1.0(4,11)]undec-8-ene | 1587 | 1000140-07-6 | nd | 0.237 ± 0.067 | 0.01 | Olefine | SH | ||
(83) | 1H-Cycloprop[e]azulene, decahydro-1,1,7-trimethyl-4-methylene- | 1588 | 072747-25-2 | nd | 1.928 ± 0.932 | 0.1 | Olefine | SH | ||
(84) | 8-epi-.gamma.-Eudesmol | 1609 | 1000374-18-4 | nd | 1.816 ± 1.604 | 0.09 | Alcohol | OCS | ||
(85) |
|
1649 | 000473-16-5 | nd | 0.944 ± 0.821 | 0.05 | Alcohol | OCS | ||
(86) | Geranyl-p-cymene | 1960 | 1000374-15-6 | nd | 1.580 ± 1.202 | 0.08 | Olefine | SH |
Percentage of the different chemical groups of components present in the two baby ginger samples.
Percentage of olefine, ester, aldehyde, alcohol, and other compounds
Percentage of OCM, SH, MH, OCS, and other compounds
As seen from Figure
The volatile compounds listed in Table
In the fresh baby ginger samples, geraniol (21, 5.78%), geranyl acetate (31, 6.07%),
In baby ginger paocai, geranyl acetate (31, 28.14%) was the only compound with an absolute content exceeding 100 mg/kg, while
The preceding difference in flavor composition of the two baby ginger samples is intrinsically related to microbial fermentation and the dissolution of some flavor compounds. As mentioned earlier by scholars, kimchi fermentation process is achieved by bacteria, yeasts, fungi, and other microorganisms; lactic acid bacteria are the most important microorganisms which affect the sensory quality of pickled vegetables. The formation of flavor is a complicated process that occurs during homolactic and heterolactic fermentation by lactic acid bacteria [
The contribution of each volatile substance to the flavor of baby ginger paocai is not only related to its relative content, but also related to its absolute content and sensory threshold. So the aroma composition of baby ginger paocai was analyzed by GC-O method in the study. In the sensory evaluation, baby ginger paocai exhibited overall “spicy,” “camphor-like,” “herbal,” “fruity,” “flowery,” “ginger-like,” and “balsamic” aroma qualities. The highest sensory scores were for ginger-like, camphor-like, flowery, and fruity aroma, while the lowest score was for woody note. With the increase of the split ratio from 10 : 1 to 200 : 1, the paocai volatile extracts of HS-SPME fiber were diluted. Fifty-eight aroma-active compounds were identified (Table
Flavor dilution factor and aroma quality of each aroma-active compound identified in baby ginger paocai.
Number |
RI | FD factor |
Aroma quality |
Number | RI | FD factor | Aroma quality |
---|---|---|---|---|---|---|---|
(1) | 944 | 50 | Woody | (30) | 1367 | 100 | Spicy |
(2) | 958 | 10 | Camphor-like | (31) | 1387 | 200 | Sweet, fruity |
(3) | 985 | 10 | Woody | (32) | 1393 | 10 | Fruity |
(4) | 1001 | 200 | Balsamic | (33) | 1395 | 50 | Fruity |
(5) | 1013 | 10 | Black pepper-like | (34) | 1397 | 50 | Fruity |
(6) | 1023 | 25 | Fruity, lemon-like | (35) | 1407 | 10 | Fruity |
(7) | 1024 | 50 | Camphor-like | (36) | 1411 | 10 | Spicy, clove-like |
(8) | 1035 | 200 | Camphor-like | (37) | 1420 | 25 | Herbal |
(9) | 1044 | 200 | Flowery | (38) | 1426 | 10 | Spicy, fennel-like |
(10) | 1054 | 200 | Flowery | (39) | 1427 | 10 | Fruity, lemon-like |
(11) | 1063 | 10 | Fruity, lemon-like | (40) | 1439 | 50 | Herbal |
(12) | 1092 | 25 | Woody | (41) | 1442 | 10 | Spicy, clove-like |
(13) | 1105 | 200 | Flowery | (42) | 1449 | 100 | Herbal |
(14) | 1132 | 25 | Flowery | (43) | 1467 | 25 | Flowery |
(15) | 1181 | 50 | Spicy, clove-like | (44) | 1478 | 200 | Ginger-like |
(16) | 1189 | 100 | Camphor-like | (45) | 1482 | 100 | Herbal |
(17) | 1196 | 10 | Spicy, clove-like | (46) | 1488 | 100 | Herbal |
(18) | 1205 | 200 | Flowery | (47) | 1491 | 50 | Flowery |
(19) | 1210 | 50 | Flowery | (48) | 1503 | 50 | Herbal |
(20) | 1238 | 200 | Fruity, lemon-like, flowery | (49) | 1505 | 200 | Fruity, balsamic |
(21) | 1260 | 200 | Bitter, flowery | (50) | 1520 | 100 | Fruity, orange-like |
(22) | 1271 | 100 | Fruity, lemon-like, flowery | (51) | 1534 | 10 | Herbal |
(23) | 1283 | 50 | Camphor-like | (52) | 1548 | 25 | Flowery |
(24) | 1292 | 100 | Fruity, rue-like | (53) | 1560 | 10 | Sweet, fruity |
(25) | 1321 | 50 | Fruity | (54) | 1608 | 50 | Herbal, camphor-like |
(26) | 1342 | 25 | Herbal | (55) | 1645 | 50 | Flowery |
(27) | 1349 | 50 | Flowery | (56) | 1689 | 100 | Camphor-like |
(28) | 1356 | 10 | Green | (57) | 1845 | 10 | Fruity |
(29) | 1360 | 10 | Fruity | (58) | 1847 | 25 | Fruity |
Woody and camphor-like were perceived at lower retention indices, followed by balsamic, flowery, spicy, and fruity. At the end of the analysis the camphor-like quality appeared again, followed by the fruity. Compounds with a balsamic note (4), camphor-like note (8), flowery note (9, 10, 13, 18, 20, and 21), fruity note (31, 49), and ginger-like note (44) were the most important aroma-active components in baby ginger paocai. Most of these aroma compounds correlated well with the sensory attributes detected in sensory evaluation. These eleven odorants were all detected in fresh baby ginger except for decanal (18). Decanal (18) might be the product of lactobacillus fermentation.
A strong fruity note was found to be the characteristic flavor of baby ginger paocai, compared with fresh baby ginger. The pleasant fruity note of baby ginger paocai could be attributed to the combined effects of cis-citral (20), geranyl acetate (31), and
The camphor-like note was a part of the typical aroma of baby ginger paocai while camphor was considered by Angel et al. [
Regarding flowery notes, compounds trans-
The results obtained by analyzing aroma compounds of baby ginger paocai and fresh baby ginger demonstrated that the aroma formation of baby ginger was significantly changed by lactic acid fermentation. The main ingredients of fresh baby ginger or baby ginger paocai belonged to alcohols, aldehydes, olefines, and esters. These volatile aroma compounds were mostly terpenoids or their derivatives.
The authors declare that there are no conflicts of interest regarding the publication of this paper.
The design of this research was accomplished by Songming Luo and guided by Biao Pu. Songming Luo interpreted the results and drafted the manuscript. Qiang Li, Anjun Chen, and Xingyan Liu collected test data.
This study was supported financially by National Natural Science Foundation of China (Grant no. 31171726) and Science and Technology Project of Sichuan Province (Grant no. 2012NZ0002). Thanks are due to Songming Luo’s wife for her great support for this work. And thanks are also due to individuals who have participated in this work.