# Distribution of Volatile Compounds in Different Fruit Structures in Four Tomato Cultivars
## 2 Results and Discussion
### Volatile Compounds in Tomato Fruits  
Table 2 exhibits the volatile compounds and their odor description, odor thresholds in water, and RI values. The solid-phase micro-extraction-gas chromatography-mass spectrometry (SPME-GC/MS) study identified 36 volatile compounds, including 13 aldehydes, 6 hydrocarbons, 5 alcohols, 4 ketones, 2 oxygen-containing heterocyclic compounds, 3 esters, 1 nitrogen compound, and 2 sulfur- and nitrogen-containing heterocyclic compounds. According to Table 3, aldehydes accounted for the highest percentage of the total volatile concentration, followed by alcohols and ketones. Among the individual compounds, cis-3-hexenal was the most abundant component, which agreed with the reports of [PERSON] et al. [16], following trans-2-hexenal, hexanal, acetone, 2-methylbutanal, and 3-methylbutanal (Table 3). Thirteen volatile compounds, which were suggested to be important tomato aroma contributors in previous studies, were identified in our study [4; 21; 22; 23], including 3-methyl butanal, 2-methyl butanal, cis-3-hexenal, hexanal, trans-2-hexenal, 3-methyl butanol, 2-methyl butanol, 1-penten-3-one, 6-methyl-5-hepten-2-one, 2-isobutyl thiazole, 1-nitro-2-phenylethyl, geranyl acetone, and methyl salicate. The biosynthetic origins of the 13 volatiles were reported previously. Based on their biosynthetic origins, these compounds can be divided into four groups: fatty acid derivatives (cis-3-hexenal, hexanal, trans-2-hexenal, 1-penten-3-one), carotenoid derivatives (6-methyl-5-hepten-2-one, geranyl acetone), amino acid derivatives (3-methyl butanal, 2-methyl butanol, 3-methyl butanol, 2-methyl butanol, and 2-isobutyl thiazole), and phenylalanine derivatives (1-nitro-2-phenylethane and methyl salicate) [1]. Odor threshold values in water, adapted from [PERSON] et al. [17]. \begin{table}
\begin{tabular}{c c c c c c} \hline \multirow{2}{*}{**Variety**} & \multirow{2}{*}{**Weight (g)**} & \multicolumn{4}{c}{**Percentage to Total Weight (\%)**} \\ \cline{3-6}  & & **Pericarp (PE)** & \multicolumn{2}{c}{**Septa and**} & \multicolumn{2}{c}{**Locular Gel**} \\  & & & **Columella (SC)** & **and Seeds (LS)** & **Stem End (SE)** \\ \hline FL47 & 206.10 & \(52.83\pm 5.37\) \({}^{\text{a}}\) & \(29.70\pm 2.55\) \({}^{\text{b}}\) & \(16.26\pm 3.86\) \({}^{\text{c}}\) & \(1.21\pm 0.27\) \({}^{\text{d}}\) \\ Tygress & 181.85 & \(54.36\pm 4.93\) \({}^{\text{a}}\) & \(27.18\pm 3.37\) \({}^{\text{b}}\) & \(17.02\pm 2.03\) \({}^{\text{c}}\) & \(1.44\pm 0.26\) \({}^{\text{d}}\) \\ Tasti-Lee & 159.35 & \(53.99\pm 2.51\) \({}^{\text{a}}\) & \(27.53\pm 1.67\) \({}^{\text{b}}\) & \(16.76\pm 2.07\) \({}^{\text{c}}\) & \(1.73\pm 0.19\) \({}^{\text{d}}\) \\ Cherokee Purple & 265.58 & \(47.34\pm 3.33\) \({}^{\text{a}}\) & \(40.24\pm 3.76\) \({}^{\text{b}}\) & \(10.09\pm 1.60\) \({}^{\text{c}}\) & \(2.33\pm 0.60\) \({}^{\text{d}}\) \\ \hline \multicolumn{6}{l}{Values are expressed as means \(\pm\) standard deviation. Different superscripts (a–d) in the same row indicate significant difference (\(p<0.05\)).} \\ \end{tabular}
\end{table} 
Table 1: Percentage to total weight per tissue in four tomato varieties.