Table 7 Volatile compounds detected in different kombucha samples after 14 days of fermentation.
Volatile compounds | % area* | |||||||
|---|---|---|---|---|---|---|---|---|
RT | K1 | K2 | K3 | K4 | K5 | K6 | K7 | |
Esters | ||||||||
Ethyl acetate | 6.19 | 5.05 | 6.60 | 8.75 | 4.80 | 2.90 | 3.64 | 3.05 |
Butanoic acid, 2-methyl-, ethyl ester | 10.34 | 1.50 | n.d | n.d | n.d | n.d | n.d | 0.91 |
Ethyl hexanoate | 17.59 | 0.85 | n.d | n.d | n.d | n.d | n.d | 0.11 |
2-methyl-2-methylbutyl butanoate | 19.37 | n.d | n.d | n.d | n.d | n.d | n.d | 0.21 |
Ethyl decanoate | 34.83 | 2.46 | 1.88 | 3.44 | 3.34 | 2.94 | 4.89 | 5.07 |
Ethyl benzeneacetate | 39.81 | n.d | n.d | n.d | 0.41 | 0.44 | 0.62 | 0.98 |
2-phenethyl acetate | 40.90 | n.d | n.d | 2.92 | 2.37 | 1.78 | 1.86 | 3.85 |
Phenethyl acetate | 40.99 | 2.32 | 4.10 | n.d | n.d | n.d | n.d | n.d |
Ethyl dodecanoate | 42.43 | 2.75 | 1.51 | 3.02 | 2.92 | 2.78 | 3.68 | 4.09 |
Ethyl hexadecanoate | 54.97 | n.d | n.d | n.d | 0.58 | 0.48 | 0.68 | n.d |
2-ethylhexyl salicylate | 55.67 | 2.12 | n.d | n.d | n.d | n.d | n.d | n.d |
Ethyl oleate | 59.63 | n.d | n.d | n.d | 0.43 | 0.20 | 0.50 | 0.79 |
Carboxylic acid | ||||||||
Acetic acid | 26.43 | 42.75 | 29.14 | 20.90 | 33.60 | 46.06 | 40.25 | 31.52 |
Isobutyric acid | 31.49 | 0.65 | 0.52 | 0.41 | 0.41 | 0.47 | 0.60 | 0.78 |
2-methylhexanoic acid | 35.47 | 5.31 | 2.79 | 2.08 | 1.82 | 1.89 | 2.63 | 3.61 |
Octanoic acid | 49.30 | 3.89 | 1.12 | 1.21 | 0.62 | n.d | 0.73 | 0.55 |
n-Decanoic acid | 54.92 | 6.05 | 1.80 | 1.41 | 0.59 | n.d | 1.02 | 1.37 |
Dodecanoic acid | 59.46 | 3.58 | 1.08 | 0.74 | n.d | n.d | n.d | n.d |
Phenols | ||||||||
4-ethyl-2-methoxy-phenol | 48.12 | 3.32 | 17.75 | 24.16 | 23.39 | 20.23 | 19.45 | 22.12 |
2-methoxy-4-propyl-phenol | 50.56 | n.d | 0.38 | 0.41 | 0.47 | 0.26 | 0.26 | 0.48 |
4-ethylphenol | 52.26 | 7.04 | 13.61 | 12.13 | 9.08 | 7.16 | 6.22 | 7.10 |
4-(2-propenyl)-phenol | 56.10 | n.d | 0.33 | 0.34 | 0.34 | 0.23 | 0.26 | 0.46 |
4-(1,1-dimethylpropyl)phenol | 57.65 | 2.69 | 1.33 | 1.00 | 0.68 | 0.44 | 0.26 | 0.30 |
Alcohols | ||||||||
Ethanol | 7.25 | 4.74 | 5.79 | 7.35 | 7.56 | 7.64 | 8.24 | 7.06 |
2-methyl-1-butanol | 16.50 | 0.95 | 0.99 | 0.98 | 0.80 | 0.56 | 0.72 | 0.88 |
Phenylethyl alcohol | 44.26 | 1.99 | 7.95 | 8.07 | 5.44 | 3.18 | 3.00 | 3.38 |
Aldehydes | ||||||||
Benzaldehyde | 29.56 | n.d | 1.42 | 0.67 | 0.35 | 0.24 | 0.34 | 0.74 |
Ketone | ||||||||
Acetoin | 20.02 | n.d | n.d | n.d | n.d | 0.13 | 0.16 | n.d |
