Volatile components of ripe tomatoes and their juices, purees and pastes

Volatile components in neutral, basic, phenolic and acidic fractions of the steam-distillate and in headspace gas trapped from two varieties of fully ripe tomato fruits and their juices, purees and pastes were analyzed by GC and GC-MS using a glass capillary column. One hundred and fifty-four compounds were identified: they were 3 sulfides, 10 aromatic hydrocarbons, 4 terpene hydrocarbons, 27 alcohols, 26 aldehydes, 13 ketones, 17 esters, 2 lactones, 7 furans, 4 pyrroles, 2 pyridines, 2 pyrazines, 2 thiazoles, 12 phenols, 16 carboxylic acids and 7 others. Of these, 39 compounds were identified for the first time in tomato fruits and their products. Generally, with the advance of the processing degree from tomato fruits to pastes, decrement of low-boiling components and increment of middle to high-boiling components were observed. In tomato purees and pastes, 14 components, which were detected in tomato fruits and juices, disappeared and 11 components, pyrrole, 2,5-dimethylpyrrole, 2-acetylpyrrole, 2-formylpyrrole, 2-methylpyrazine, 2,6-dimethylpyrazine, dibenzofuran, o-phenylanisole, farnesol, indole and diphenylamine, were newly produced. 2-Acetylpyrrole. 2-formylpyrrole and the above pyrazines, which have respectively a burnt odor, are considered to be important for the characteristic heated aroma of tomato puree and paste.