# Impact of a Microbial Cocktail Used as a Starter Culture on Cocoa Fermentation and Chocolate Flavor
## 2 Results
### Chemical Changes During Fermentation
#### 2.2.2 Volatile Compounds  
A total of 37 volatile compounds were detected by Gas Chromatography Mass Spectrometry (GC-MS) at the beginning (0 h), and a total of 38 volatile compounds at the end (144 h), of the non-inoculated fermentation. While in the inoculated fermentation, a total of 37 volatile compounds were detected at the beginning (0 h) and a total of 34 volatile compounds at the end (144 h), as presented in the Table 2. \begin{table}
\begin{tabular}{c c c} \hline
**Compounds** & **Odor Description \({}^{\text{a}}\)** & **Sample Found** \\
**Acids** & & \\
4-Hydroxybutanoic acid & & PH15I Ch \\
4-Hydroxybutyric acid & & PH15 NI Ch \\ Acetic acid & Sour, astringent & PH15 NI 144 h \\ Benzaceae acid & PH15 NI Ch, PH15I Ch \\ Butanoic acid & Rancid, butter, cheese & PH15 NI Ch, PH15I Ch \\ Hexanoic acid & Sweat, pungent & All \\ Isovaleric acid & Sweat, rancid & All \\ Octanoic acid & Sweaty, fatty & PH15 NI (0 h and 144 h), PH15I 144 h, PH15 NI Ch \\ Pentanoic acid & & PH15 NI Ch, PH15I Ch \\ Valeric acid & Sweat, acid, rancid & PH15 NI Ch, PH15I Ch \\ \hline
**Alcohols** & & \\
2-Ethyl-1-hexanol & PH15 NI Ch \\
1-Hexanol & & PH15 NI (0 h and 144 h), PH15I 0 h \\
1-Methoxy-2-butanol & & PH15 NI Ch, PH15I Ch \\
1-Nonanol & & PH15 NI Ch, PH15I Ch \\
1-Octanol & Fatty, waxy & All \\
1-Penten-3-ol & & PH15 NI 0 h \\
2,3-Butanediol & Cocoa butter & PH15 NI (0 h and 144 h), PH15I 144 h, PH15I Ch \\
2,4-Pentanediol & & PH15 NI 0 h, PH15I 0 h, PH15 NI Ch, PH15I Ch \\
2-Furamethanol & & PH15 NI Ch \\
2-Heptanol & Sweet, citrusy & PH15 NI (0 h and 144 h), PH15I (0 h and 144 h) \\
2-Hexanol & Fruity, green & PH15 NI 0 h, PH15I 0 h \\
2-Pentanol & Green, mild green & PH15 NI Ch, PH15I Ch \\
3-Methyl-1-butanol & Malty, chocolate & PH15 NI (0 h and 144 h), PH15I (0 h and 144 h) \\ Benzyl alcohol & Sweet, flower & All \\ Furfuryl alcohol & & PH15 NI Ch \\ Guicaol & Smoke, sweet & PH15 NI 144 h, PH15I 144 h \\ Phenylethyl Alcohol & Honey, rose, caramel & All \\
**Aldehydes and Ketones** & & \\
3-methylpentanal & & PH15 NI 0 h, PH15I 0 h, PH15 NI Ch, PH15I Ch \\ (_E_)-2-Heptanal & & PH15 NI 0 h, PH15I 0 h \\ (_E_)-2-Nonen & Tallowy green & PH15 NI 0 h, PH15I 0 h \\ (_E_)-2-Octanal & Fatty, waxy & PH15 NI 0 h, PH15I 0 h \\ (_E_)-2-Undecenal & & PH15 NI 0 h, PH15I 0 h \\ (_E,_E_)-2,4-heptadiene & & PH15 NI 0 h, PH15 NI Ch, PH15I Ch \\
1-(2-hydroxyphenyl)ethanone & & PH15 NI 0 h, PH15I 0 h \\
2(5_H_)-Furanone & Caramel-like & PH15 NI Ch, PH15I Ch \\
2-Heptanone & & PH15 NI (0 h and 144 h), PH15I (0 h and 144 h) \\
2-Hydroxyphenyl methyl ketone & & PH15 NI 144 h, PH15I (0 h and 144 h) \\
2-Dnonane & & PH15 NI 144 h, PH15I (0 h and 144 h) \\
2-Phenyl-2-butenal & Sweet, roasted & PH15 NI 144 h, PH15I 144 h, PH15 NI Ch, PH15I Ch \\
2-Undecenal & & PH15 NI (0 h and 144 h), PH15I (0 h and 144 h) \\
3-Methyl-1,2-cyclopentanedione & & PH15 NI Ch, PH15I Ch \\
3-Penten-2-one & & PH15 NI Ch \\
4-hydroxy-3-methylbutanal & & PH15 NI 0 h, PH15I 0 h \\
4-Methyllyhexanal & & PH15 NI Ch, PH15I Ch \\
5-Methyl-2-furaldehyde & & PH15 NI Ch, PH15I Ch \\
5-Methyl-2-phenyl-2-hexenal & & PH15 NI Ch, PH15I Ch \\ \hline \end{tabular}
\end{table} 
Table 2: Volatile compounds identified by Headspace—Solid Phase Microextraction—Gas Chromatography Mass Spectrometry (HS–SPME GC–MS) during fermentation times (0 h and 144 h) and in chocolate samples, and the reference odor of each compound.