Table 1.
Volatiles identified at end of spontaneous and inoculated fermentations and in the chocolates produced by these process. Means represent averages of GC–MS peak areas including biological and technical replicates
| Group | KI | Compound | Mean GC–MS peak area | Odora | |||
|---|---|---|---|---|---|---|---|
| Fermentation | Chocolate | ||||||
| Spontaneous | Inoculated | Spontaneous | Inoculated | ||||
| Aldehydes | 1.285 | 2-Phenyl-2-butenal | ND | ND | 8751 | 16,746 | Flowery, cocoa, roasted, rum |
| 1.504 | 5-Methyl-2-phenyl-2-hexenal | ND | ND | 1065 | 1815 | Sweet, roasted cocoa | |
| 502 | Acetaldehyde | 154,536 | ND | ND | ND | Green leaves, fruity | |
| 955 | Benzaldehyde | 83,053 | 17,322 | 88,963 | 95,355 | Nutty | |
| 1053 | Benzeneacetaldehyde | 390,316 | 359,250 | 101,012 | 110,323 | ||
| 561 | 2-Methyl-butanal | 20,517 | 18,305 | ND | ND | Malty, chocolate | |
| 554 | 3-Methyl-butanal | ND | ND | 17,852 | 16,513 | Malty, chocolate | |
| 1.209 | Decanal | ND | ND | 5074 | 4521 | Pungent, green | |
| 715 | Hexanal | ND | ND | 6690 | 6995 | Green | |
| 1.113 | Nonanal | ND | ND | 36,644 | 40,941 | Soapy–fruity | |
| 1.006 | Octanal | ND | ND | 5117 | 5419 | Orange (peel) | |
| Total | 648,422 | 394,877 | 271,168 | 298,628 | |||
| Ketones | 529 | 2,3-Butanedione | 676,517 | 580,905 | 24,400 | 21,096 | Buttery |
| 870 | 2-Acetoxy-3-butanone | 196,754 | 254,449 | ND | ND | ||
| 863 | 2-Heptanone | 285,723 | 1,219,458 | ND | ND | Fruity, flowery | |
| 1102 | 2-Nonanone | 1,509,265 | 1,306,206 | 7212 | 10,671 | Flowery, fatty | |
| 577 | 2-Pentanone | 59,818 | 160,093 | ND | ND | Fruit | |
| 1299 | 2-Undecanone | 5339 | 3126 | 2617 | 3412 | Fruity, citrus | |
| 593 | Acetoin | 1,247,111 | 1,471,769 | 133,167 | 103,088 | Butter, cream | |
| 1077 | Acetophenone | 112,709 | 138,679 | 8316 | 10,675 | Flowery, sweet | |
| 993 | 2-Octanone | ND | 36,624 | ND | ND | Bitter, green | |
| 561 | 1-Hydroxy-2-propanone | ND | ND | 10,647 | 10,700 | ||
| 1.081 | 3,5-Octadien-2-one | ND | ND | 18,757 | 12,083 | ||
| 508 | Acetone | ND | ND | 18,281 | 10,763 | ||
| Total | 4,093,236 | 5,171,309 | 223,397 | 182,488 | |||
| Esters | 844 | Isoamyl acetate | 741,420 | 1,778,463 | ND | ND | Banana |
| 912 | 3-Methyl-2-butenyl acetate | 6764 | ND | ND | ND | ||
| 1265 | 2-Phenethyl acetate | 265,949 | 440,867 | 173,104 | 137,198 | rose | |
| 1019 | Hexyl acetate | 7784 | 4291 | ND | ND | Fruit | |
| 516 | Methyl acetate | 114,257 | 78,930 | ND | ND | ||
| 899 | Amyl acetate | 5144 | ND | ND | ND | Banana | |
| 1253 | Ethyl phenylacetate | 81,801 | 68,638 | 22,975 | 42,837 | Fruity, sweet, honey-like | |
| 1179 | Ethyl benzoate | 28,783 | 37,781 | ND | ND | ||
| 1185 | Diethyl succinate | 3662 | ND | ND | ND | Fruity | |
| 1393 | Ethyl caprate | 13,465 | 50,641 | 63,890 | 25,310 | Fruity | |
| 1596 | Ethyl laurate | 4449 | 10,099 | 60,420 | 30,319 | ||
| 537 | Ethyl Acetate | 10,239,048 | 11,451,977 | ND | ND | ||
| 1.995 | Ethyl palmitate | ND | ND | 12,333 | 8373 | ||
| 1003 | Ethyl hexanoate | 10,497 | 47,898 | ND | ND | Fruity | |
| 673 | Isobutyl acetate | 162,714 | 352,913 | ND | ND | Banana | |
| 1.354 | Methyl anthranilate | ND | ND | 6928 | 5591 | ||
| 599 | Propyl acetate | 88,276 | ND | ND | ND | ||
| 1199 | Ethyl octanoate | 52,887 | 218,199 | 6030 | 3446 | Fruity | |
| 745 | Ethyl 2 hydroxypropanoate | 30,157 | ND | ND | ND | ||
| 652 | Ethyl isobutyrate | 8890 | 7828 | ND | ND | ||
| 968 | Pentyl propanoate | ND | 2756 | ND | ND | ||
| 1.795 | Tetradecanoic acid, ethyl ester | ND | ND | 16,691 | 9003 | ||
| Total | 11,865,947 | 14,551,281 | 362,371 | 262,077 | |||
| Acids | 559 | Acetic acid | 7,191,474 | 7,434,026 | 4,499,426 | 3,865,523 | |
| 1.363 | Decanoic acid | ND | ND | 6443 | 3301 | ||
| 1953 | Hexadecanoic acid | 3145 | 4817 | 6839 | 4006 | ||
| 1.177 | Octanoic acid | ND | ND | 7889 | 7395 | Sweaty | |
| 949 | 4-Methyl-pentanoic acid | ND | ND | 9537 | 9425 | ||
| Total | 7,194,619 | 7,438,843 | 4,530,134 | 3,889,650 | |||
| Alcohol | 614 | 2-Methyl-1-butanol | 35,066 | 83,248 | ND | ND | |
| 620 | 3-Methyl-1-butanol | 96,800 | 197,046 | ND | ND | ||
| 1.036 | 2-Ethyl-1-hexanol, | ND | ND | 32,185 | 23,009 | Rose, sweet, citrus, floral | |
| 879 | 2-Heptanol | 2,056,607 | 2,967,099 | 19,943 | 30,998 | ||
| 1110 | 2-Nonanol | 1,267,603 | 518,527 | 14,847 | 30,358 | Fruity | |
| 1005 | 2-Octanol | 35,023 | 24,900 | ND | ND | ||
| 585 | 2-Pentanol | 749,097 | 731,449 | ND | ND | ||
| 721 | 4-Methyl-2-pentanol | 15,442 | ND | ND | ND | ||
| 506 | Ethanol | 1,695,287 | 3,210,905 | 91,428 | 92,375 | ||
| 1126 | Phenylethyl Alcohol | 326,557 | 467,154 | 192,981 | 174,551 | ||
| Total | 6,277,482 | 8,200,328 | 351,384 | 351,291 | |||
| Pyrazines | 1.171 | 2,3,5-Trimethyl-6-ethylpyrazine | ND | ND | 8769 | 11,374 | Candy, sweet |
| 1.009 | 2,3,5-Trimethylpyrazine | ND | ND | 61,126 | 46,873 | Cocoa, roasted | |
| 910 | 2,3-Dimethylpyrazine | ND | ND | 6887 | 6594 | Caramel, cocoa | |
| 1.098 | 2,3,5,6-Tetramethyl-pyrazine | ND | ND | 167,420 | 131,938 | Roasted, chocolate | |
| Total | 0 | 0 | 244,202 | 196,779 | |||
| Furano | 813 | Furfuryl alcohol | ND | ND | 25,704 | 20,347 | Caramel-like, sweet |
| Others | 1.074 | Ethanone, 1-(1 H-pyrrol-2-yl)- | ND | ND | 105,604 | 96,154 | |
| 1035 | D-Limonene | 2632 | ND | ND | ND | ||
| Total | 2632 | 0 | 105,604 | 96,154 | |||
| Total compounds | 30,082,338 | 35,756,638 | 6,113,964 | 5,297,454 | |||
aObtained from the literature. ND = Not detected