Analysis of Volatile Flavor Compounds of Sardine (Sardinops melanostica) by Solid Phase Microextraction

• Published in: Journal of food science Vol. 73; no. 1; pp. S83 - S88
• Main Authors: Ganeko, N, Shoda, M, Hirohara, I, Bhadra, A, Ishida, T, Matsuda, H, Takamura, H, Matoba, T
• Format: Journal Article
• Language: English
• Published: Malden, USA Blackwell Publishing Inc 01-01-2008; Institute of Food Technologists; Wiley Subscription Services, Inc
• Subjects: Animals; Biological and medical sciences; Chromatography, Gas - methods; Consumer Behavior; Fatty Acids, Volatile - analysis; Fish; Fish and seafood industries; Fishes; fishy flavor; flavor; flavor compounds; Flavors; Food industries; Food Preservation - methods; Food processing industry; Food science; Fundamental and applied biological sciences. Psychology; Gas Chromatography-Mass Spectrometry - methods; Humans; Hydrogen-Ion Concentration; Methylamines - analysis; microextraction; Odorants - analysis; Oxidation-Reduction; sardine; sardines; Sardinops; Sardinops melanostica; sensory properties; solid phase extraction; solid phase microextraction; Solid Phase Microextraction - methods; Solvent extraction processes; Taste; volatile flavor compounds; Volatilization; Volatile compound; Solid phase microextraction; Sardine; Edible fish; Analysis; fishy flavor sardine; volatile flavor compounds; Flavor
• ISSN: 0022-1147; 1750-3841
• DOI: 10.1111/j.1750-3841.2007.00608.x

Generally the main component of fishy flavor is considered to be trimethylamine. On the other hand, carbonyl compounds, produced from oxidation of polyunsaturated fatty acid by lipoxygenase or by autoxidation, might have some contribution to the fishy flavor. Since sardine skin contains high levels of polyunsaturated fatty acids and lipoxygenase, carbonyl compounds may be generated more easily than trimethylamine. In this study, volatile flavor compounds of sardine were analyzed by gas chromatograph-mass spectrometry and gas chromatograph-olfactometry combined with solid phase microextraction. Then, the flavor components that contribute to fishy flavor were identified. At normal pH (6.2), trimethylamine was not detected or sensed from the fresh sardines. When the pH was raised, the amount of trimethylamine became higher. Trimethylamine flavor was weak at pH 9 and strongly sensed at pH 11 or higher. On the other hand, 33 other compounds were positively or tentatively identified, including 8 hydrocarbons, 5 ketones, 1 furan, 1 sulfur compound, 12 aldehydes, and 6 alcohols in fresh sardines. Among them, 2,3-pentanedione, hexanal, and 1-penten-3-ol were the main components. Forty-seven flavors were detected by gas chromatograph-olfactometry. Among them, paint-like (1-penten-3-one), caramel-like (2,3-pentanedione), green-like (hexanal), shore-like ((Z)-4-heptenal), citrus note (octanal), mushroom-like (1-octen-3-one), potato-like (methional), insect-like ((E,Z)-2,6-nonadienal), and bloody note (not identified) were strongly sensed. From the aforementioned results, it can be concluded that these compounds rather than trimethylamine contributed to fresh sardine flavor.