# Flavour Volatiles of Fermented Vegetable and Fruit Substrates: A Review
## 3 Results  
### Research Profiles  
A total of 35 scientific papers met the criteria used for the review. An overview of the study conditions reported in the papers is presented in Table 2. The number of papers published by year was: 2017 (4 articles, 11.44%); 2018 (10 articles, 28.57%); 2019 (7 articles, 20%); 2020 (2 articles, 5.71%); 2021 (10 articles, 28.57%); and 2022 (2 articles, 5.71%). The papers were published in 20 different journals, which had an impact factor ranging from 1.713 to 7.514 (Figure 2). The greatest number of papers (6) were published in Food Chemistry. \begin{table}
\begin{tabular}{c c c} \hline
**Inclusion Criteria** & **Exclusion Criteria** \\ \hline Original research papers published in recognized journals & Papers published in predatory journals \\ \hline Fermented flavours of fruit and vegetable substrates & Fermented flavours of wine, beer, cocoa, meat, and milk-based substrates \\ Plant juices added in milk substrates \\ \hline \end{tabular}
\end{table} 
Table 1: Inclusion and exclusion criteria for screening papers. \begin{table}
\begin{tabular}{c c c c c c} \hline
**No** & **Substrate** & **Micro-organisms** & **Fementation** & **Extraction and Analysis** & **Major Flavour** & **Reference** \\  & & & **Conditions** & **of Flavour Volatiles** & **Volatile Classes** & **Reference** \\ \hline \multirow{4}{*}{1} & Apple, carrot, tomato, cucumber, and have mixed juice & _L. plantarum_ & Inoculum: 2\% (/v) & \begin{tabular}{c} Acids (1) \\ Alcoholus (2) \\ Aldehydes (3) \\ Esters (2) \\ Ketones (2) \\ \end{tabular}  & \multirow{4}{*}{[17]} \\  & & mixed juice & _L. acidophilus_ & & & \\  & & _L. fermentatum_ & & & \\  & & & & & \\ \hline \multirow{4}{*}{2} & & & & & \\  & & & & & \\  & & & & & \\  & & & & & \\  & & & & & \\  & & & & & & \\  & &  
\begin{table}
\begin{tabular}{c c c c c c c c} \hline \hline
**No** & **Substrate** & **Micro-organisms** & **Fementation** & **Extraction and Analysis** & **Major Flavour** & **Reference** \\  & & & **Conditions** & **of Flavour Volatiles** & **Volatile Classes** & **Reference** \\ \hline  & & & Inoculum: 5\% mass ratio & & Acids (8) & \\  & & & at 37 \({}^{\circ}\)C for 48 h & & Alcohols (20) & \\
7 & Papaya juice & _L. acidophilus_ & _L. plantarum_ & 5\% of edible glucose and & & Aldehydes (10) & \\  & & & 5\% of skim milk powder & & Estracted and analysed & Esters (23) & [23] \\  & & & & using HS-SPME-GC-MS & Ketones and & \\  & & & 5\% of skim milk powder & & lactones (13) & \\  & & & added into the juice & & Phenols (3) & \\ \hline  & & & & Alcohols (23) & \\  & & & & Alkhades (15) & \\  & & & & Alkhades (8) & \\  & & & Extracted and analysed & & Benzere & \\  & & & Inoculum: 7.0 log & by Purge and trap & & derivatives (5) & \\
8 & Pomegranate juice & _L. plantarum_ & CFU/mL & coupled with gas & Esters (14) & \\  & & & at 30 \({}^{\circ}\)C for 120 h & chromatography-mass & Furans (9) & [24] \\  & & & at 30 \({}^{\circ}\)C for 120 h & spectrometry & Ketones (24) & \\  & & & & (PT-GC-MS) & Suphur & \\  & & & & compounds (6) & \\  & & & & Terpenes and & \\  & & & & norisoprenoids (8) & \\  & & & & Others (2) & \\ \hline  & & & Inoculum: 0.5\% (\(\
icefrac{{}}{\
u}\)) & & & \\  & & _L. plantarum_ & & 37 \({}^{\circ}\)C for 20h under & & \\  & & & & anaerobic conditions & & Alcohols (14) & \\
9 & Goj berry/wolfberry & _B. biclassensis_ & _B. biclassensis_ & & & Aldehydes (12) & \\  & & & & &  
\begin{table}
\begin{tabular}{c c c c c c c} \hline \hline  
\begin{table}
\begin{tabular}{c c c c c c c} \hline
**No** & **Substrate** & **Micro-organisms** & **Fementation** & **Extraction and Analysis** & **Major Flavour** & **Reference** \\  & & & **Conditions** & **of Flavour Volatiles** & **Volatile Classes** & **\\ \hline  & & & Inoculum: 7.0\(\&\)8.0 \(\&\) & Acids (3) & \\  & & & & spores /mL & Volatiles extracted by & Aldehydes (7) & \\
24 & Tomato pomace & _T.