TABLE 1.
Volatile compounds identified in soy juice (SJ) unfermented and fermented with Lactobacillus delbrueckii subsp. delbrueckii CIRM-BIA865 throughout fermentationa
| Concentration (arbitrary units) for sample | |||||
|---|---|---|---|---|---|
| Volatile compound | Unfermented SJ | Fermented SJ | |||
| pH 7.2, 0.0 h | pH 6.5, 3.3 h | pH 6.0, 5.8 h | pH 5.0, 10.8 h | pH 4.6, 26.6 h | |
| Hexanal (a) | 8.8 ab | 9 a | 8.8 b | 8.6 c | 8.5 c |
| Hept-2-enal (a) | 7.4 b | 7.5 b | 7.5 b | 7.5 b | 7.7 a |
| Propan-1-ol (b) | 7.2 a | 7.3 a | 7.2 a | 6.9 b | 6.9 b |
| Pentanal (a) | 8.1 a | 8.1 a | 8a | 7.8 b | 7.8 b |
| 3-Methylbutanal (a) | 8.2 a | 8 b | 7.9 b | 7.8 b | 7.8 b |
| 1-Butanol (b) | 9 a | 9.1 a | 9 a | 8.9 a | 8.6 b |
| 2-Pentylfuran (g) | 9 a | 9.1 a | 9 a | 8.9 a | 8.6 b |
| 2-Ethylfuran (g) | 8.6 b | 8.9 a | 8.8 ab | 8.8 ab | 8.6 b |
| Propan-2-one (c) | 9 a | 8.9 a | 9 a | 8.8 a | 8.9 a |
| 2-Methylpropan-1-ol (b) | 6.1 a | 6.6 a | 6.4 a | 6.8 a | 6.5 a |
| 2-Butanone (c) | 8.1 a | 8.1 a | 8.1 a | 8.2 a | 8.2 a |
| Ethyl acetate (e) | 7.4 a | 7.6 a | 7.3 a | 7.4 a | 7.7 a |
| Propanoic acid (d) | 8 a | 7.9 a | 8.3 a | 7.8 a | 8.1 a |
| Benzaldehyde (a) | 7.8 a | 7.9 a | 7.8 a | 7.9 a | 7.9 a |
| Acetaldehyde (a) | 9.2 a | 9.2 a | 9.3 a | 9.2 a | 9.3 a |
| 2,5-Dimethylpyrazine (f) | 7.3 b | 7.5 ab | 7.5 ab | 7.6 a | 7.7 a |
| Formic acid (d) | 7.3 b | 7.5 ab | 7.5 ab | 7.5 ab | 7.6 a |
| Acetic acid (d) | 9.1 b | 9.5 ab | 9.5 ab | 9.4 ab | 9.7 a |
| Butanoic acid (d) | 7.3 c | 7.5 bc | 7.4 bc | 7.6 ab | 7.8 a |
| Pentanoic acid (d) | 7 c | 7.5 bc | 7.5 bc | 7.7 ab | 8.2 a |
| Hexanoic acid (d) | 7.5 c | 7.7 b | 7.7 bc | 7.8 ab | 8.2 a |
| Heptanoic acid (d) | 6.8 c | 6.9 bc | 6.9 abc | 7.1 ab | 7.3 a |
| Octanoic acid (d) | 7.1 b | 7.4 ab | 7.5 ab | 7.5 ab | 7.7 a |
| Nonanoic acid (d) | 7.4 b | 7.7 ab | 7.8 ab | 7.7 ab | 7.9 a |
| Decanoic acid (d) | 6.4 b | 6.7 ab | 6.7 ab | 6.8 ab | 6.9 a |
| Diacetyl (c) | 7.8 b | 7.8 b | 8 a | 8.1 a | 8.1 a |
| Acetoin (c) | 7.7 c | 7.9 c | 7.9 c | 8.5 b | 8.9 a |
| 3-Hydroxypropan-2-one (c) | 8.2 c | 8.3 c | 8.3 c | 8.6 b | 8.8 a |
| Oxolan-2-one (c) | 6.1 c | 6.1 bc | 6.2 abc | 6.3 abc | 6.3 a |
| Heptan-2-one (c) | 7.8 b | 8.1 ab | 8 a | 8.1 a | 8.2 a |
| Nonan-2-one (c) | 6.7 e | 7 d | 7.2 c | 7.4 b | 7.6 a |
| 1-Pentanol (b) | 7.6 b | 7.7 ab | 7.6 ab | 7.7 ab | 7.7 a |
| 1-Hexanol (b) | 7.6 c | 7.8 b | 7.9 b | 8.1 a | 8.2 a |
| Phenylmethanol (b) | 6.7 c | 6.9 b | 6.9 b | 6.9 ab | 7.1 a |
| 1-Phenylethanol (b) | 5.9 c | 6.2 b | 6.2 b | 6.3 ab | 6.5 a |
a
The concentrations are expressed as log 10 concentrations of the abundance of a specific m/z fragment for each compound. Letters after the concentrations indicate statistical differences from a Tukey test with an alpha error of 0.05 between the changes of concentration over time for a given compound. The letter in brackets indicates the nature of compound: aldehyde (a), alcohol (b), ketone (c), acid (d), ester (e), pyrazine (f), and furan (g).