## 2 Results
### Profile of Volatile Compounds
\begin{table}
\begin{tabular}{c c c c c} \hline \hline
**Compound** & **Substrate** & **Microorganism** & **Fold-Change a** & **Descriptor b** \\ \hline \multirow{4}{*}{Anisole} & Brewer’s spent grain & _P. camemberti_ & 8 & \\  & Brewer’s spent grain & _P. cinnabarius_ & 786 & \\  & Orange pomace & _A. niger_ & 21 & Aniseed \\  & Orange pomace & _P. cinnabarius_ & 351 & \\ \hline \multirow{2}{*}{Benzaldehyde} & Brewer’s spent grain & _P. cinnabarius_ & 2 & \\  & Orange pomace & _A. niger_ & 2 & \\ \hline
1,2-dimethoxybenzene & Orange pomace & _A. niger_ & 92 & Insect attractant \\ \hline
1,4-Dimethoxybenzene & Onion pulp & _P. camemberti_ & 164 & Intense sweet, floral \\ \hline
3,4-Dimethylstyrene & Orange pomace & _A. niger_ & 150 & Green, floral, smoky \\  & Orange pomace & _P. camemberti_ & 245 & \\ \hline \multirow{4}{*}{Benzoic acid} & Carrot pomace & _P. cinnabarius_ & 272 & \\  & Kiwifruit peels & _P. cinnabarius_ & 29 & Balsamic \\  & Onion pulp & _P. cinnabarius_ & 138 & \\ \hline \multirow{2}{*}{Methyl benzoate} & Orange pomace & _P. camemberti_ & 16 & Feijoa, ylang ylang, \\  & Orange pomace & _P. cinnabarius_ & 33 & wintergreen \\  & Orange pomace & _A. niger_ & 27 & \\ \hline \multirow{2}{*}{Benzyl alcohol} & Brewer’s spent grain & _P. camemberti_ & 31 & Precursor and solvent \\  & Brewer’s spent grain & _P. cinnabarius_ & 17 & \\ \hline \(\beta\)-Pinene & Kiwifruit peels & _A. niger_ & 2 & Herbal, pine \\ \hline \multirow{2}{*}{\(\beta\)-Myrcene} & Apple pomace & _A. oryzae_ & 2 & \\  & Kiwifruit peels & _P. camemberti_ & 2 & \\ \hline \multirow{2}{*}{Sabinene} & Brewer’s spent grain & _P. camemberti_ & 8 & Spicy, black pepper \\  & Brewer’s spent grain & _P. camemberti_ & 15 & \\  & Brewer’s spent grain & _P. cinnabarius_ & 13 & Musty, chocolate \\ \hline \multirow{4}{*}{3-methylbutanal} & Carrot pomace & _P. cinnabarius_ & 61 & \\  & Kiwifruit peels & _P. cinnabarius_ & 33 & \\  & Kiwifruit peels & _P. camemberti_ & 4 & \\  & Onion pulp & _A. oryzae_ & 15 & \\  & Onion pulp & _A. niger_ & 8 & \\  & Brewer’s spent grain & _A. niger_ & 11 & chocolate, peach \\  & Brewer’s spent grain & _A. oryzae_ & 10 & \\  & Onion pulp & _A. oryzae_ & 307 & \\  & Onion pulp & _A. niger_ & 53 & \\ \hline Ethyl isovalerate & Apple pomace & _A. niger_ & 210 & Fruity \\ \hline (E)-Cinnemaldehyde & Red grape marc & _A. oryzae_ & 40 & Cinnamon \\ \hline \multirow{2}{*}{Cyclopentanone} & Kiwifruit peels & _A. oryzae_ & 37 & \\  & Kiwifruit peels & _A. niger_ & 17 & Minty \\ \hline Decanal & Olive cake & _P. cinnabarius_ & 5 & Citrus \\ \hline (D)-Limonene & Carrot pomace & _A. niger_ & 6 & Citrus \\ \hline Ethyl tightate & Red grape marc & _A. niger_ & 129 & Tutti frutti, green olive \\ \hline Methyl heptanoate & Carrot pomace & _P. cinnabarius_ & 106 & Fruity, green, waxy \\ \hline \multirow{4}{*}{Hexanal} & Brewer’s spent grain & _A. oryzae_ & 3 & \\  & Kiwifruit peels & _P. cinnabarius_ & 4 & Fresh cut grass \\  & Olive cake & _P. cinnabarius_ & 10 & \\ \hline \multirow{4}{*}{Methyl hexanoate} & Apple pomace & _P. cinnabarius_ & 133.85 & \\  & Carrot pomace & _P. cinnabarius_ & 75.89 & Pineapple, fatty \\ \cline{1-1}  & Orange pomace & _P. cinnabarius_ & 17.40 & \\ \hline Hexyl valerate & Apple pomace & _A. niger_ & 1.49 & Green, brandy \\ \hline \hline \end{tabular}
\end{table} 
Table 1: _Cont._Four compounds were short-listed for identity confirmation, and quantification from the fermented substrates due to their commercial relevance: methyl benzoate, detected only in the headspace of orange pomace fermented by the different fungi except by _Aspergillus oryzae_ (Tables 1 and 2, Figure 2); phenylacetaldehyde, detected in the headspace of different substrates fermented by different fungi (Table 1, Figure 2); 1-octen-3-ol, detected in the headspace of all fermentations (Table 1, Figure 2); and phenylethyl alcohol, only detected in the headspace of brewery spent grain fermented by _P. cinnabarinus_ (Tables 1 and 2, Figure 2).