| Sciaenops ocellatus has a abundant nutritional value and a nicer function on health protection. It contains a variety of inorganic salts, vitamins and trace elements which have an important role on human growth and development. As a kind of commercial marine fish with high protein and low fat, Sciaenops ocellatus is now one of the vendible slap-up species and has a high production of the worldwide.Breeding in shallow sea, Sciaenops ocellatus produces a lot of metabolin for its active vital movement and enzyme system. Besides, feeding it with fishmeal or putrefactive fish and shrimp can cause more full-bodied fishiness. All of these make against its production's exploiture and sustainable development of aquatic farming, and the most important is many consumers can't accept it.For the fishiness problem of Sciaenops ocellatus, this paper took Sciaenops ocellatus as sample, Selected several typical microorganisms, done a pilot study on the deodorization technology.1.Optimized the technological parameter of deodorization in Bacillus natto. the optimization parameters was mixed with 15.0%NaCl, 6.0%glucose and 0.5ml/g (5.5×1010个/ml) enrichment medium volume of Bacillus natto, fermented 12.0h at 30℃. Fermented by Bacillus natto, aldehydes, ketones, alkanes in fish were greatly reduced, Aromatic class was decreased from 33.7% to 0.43%, the main fishiness substances such as hexanal was decreased from the original content of 10.99% to 4.17%, Heptanal was 6.52% to 1.98%, Octanal was 9.2% to 1.85%, Pentanal was 1.0% to 0. a lot of other alcohols,aldehydes, and hydrocarbons were produced. In addition, there was a large proportion of ethyl acetate which has fruit aroma , reached to 20.03%, benzene acetaldehyde, indole, etc. is also abundant flavor.2.Optimized the technological parameter of deodorization in tea fungus. the optimization technological parameter was mixed with 5.0%tea fungus, 4.0%Medium and 4.0%glucose, fermented 6.0h at 35℃.Fermented by tea fungus, saturated unbranched aldehydes were almost utilized, the main fishiness substances such as hexanal was decreased from the original content of 10.99% to 3.23%, Heptanal was 6.52% to 1.16%, Octanal was 9.2% to 1.45%, Pentanal was 1.0% to 0.meawhile it produced new aldehydes which had aromatic smell, fruit and good flavor. acid substances was produced like Nonanoic acid,Octanoic acid,Heptanoic acid,Benzoic acid and so on. In addition, some furan and terpene arisen in the fermented fish also had a certain contribution on the fermentation.3.Optimized the technological parameter of deodorization in three different kinds of Lactobacillus. From the single factor tests and detected by the Alpha MOSαFOX 4000 electronic nose, three kinds of Lactobacillus on the fish available to the flavor was in descending order of Lactobacillus A ( Lactobacillus plantarum )> Lactobacillus C ( Lactobacillus casei )>Lactobacillus B(Lactobacillus ).the optimization parameters of deodorization in Lactobacillus A was mixed with 4.0% glucose and 0.25ml/g(2.1×1011/ml) enrichment culture medium volume of Lactobacillus A, fermented 5.0h at 28℃.the optimization parameters of deodorization in Lactobacillus C was mixed with 4.0% glucose and 0.25ml/g(1.5×1012个/ml) enrichment culture medium volume of Lactobacillus C, fermented 6.0h at35℃.the optimization parameters of deodorization in Lactobacillus B was mixed with 4.0% glucose and 0.25ml/g(5.8×1012个/ml)enrichment culture medium volume of Lactobacillus B, fermented 6.0h at 28℃.Fermented by Lactobacillus A, Alkanes was decreased from 5.43% to 2.07% when Aromatic Class was decreased from 33.7% to 4.66%, Heptanal was decreased from 6.52% to 0, Octanal was decreased from the original content of 9.2% to 1.64%, Nonanal was 7.2% to 2.5%.After fermented it produced a lot of new flavor substances, included a lot of aldehydes, acids and furans. Many substances were accessories of chemical fragrance industry. Meanwhile,so many acids were produced, among them, the content of acetic acid (3.38%), pelargonic acid (2.54%)and caproic acid (4.51%)were more abundant.Fermented by Lactobacillus C, Heptanal was decreased from 6.52% to 0,Undecanal was also decreased from 1.17% to 0, Nonanal was decreased from the original content of 7.2% to 2.93%. Alkanes, Alkenes and Aromatics class were almost fully utilized, it produced new substances which has aromatic smell, fruit and good flavor.Such as ethyl-Benzaldehyde, (E)-2-methyl-2-Butenal, 5-(methylenecyclopropyl)-Pentanal, 2,3-Butanedione, bis(2-methylpropyl) ester-1,2-Benzenedicarboxylic acid, 2-pentyl-Furan. Among the acids which just produced, the content of caproic acid (2.79%) and pelargonic acid (2.33%) were more abundant.Fermented by Lactobacillus B, the original volatile substances were not completely utilized, Hexanal was decreased 3.27 %, Nonanal was decreased 3.39%. Other acids such as Nonanoic acid reached to 0.79%, Acetic acid was 1.05%, Hexanoic acid was 2.76%. therefore, the improvement of overall flavor in Lactobacillus B is not obvious. 4. Screening of the most effective deodorization strain. three kinds of Lactobacillus on the fish available to the flavor in descending order of Lactobacillus A>Lactobacillus C>Lactobacillus B. From the single factor tests,the samples dealed with the optimization parameters of deodorization in Lactobacillus A and Lactobacillus C are better than others, the samples dealed with Lactobacillus B and tea fungus are no significant difference,but the samples dealed with Bacillus natto is the worst. Comprehensive consideration, the most effective deodorization strain is Lactobacillus A(Lactobacillus plantarum).5.Optimized the technological parameter of deodorization in Mixed strians.the optimization parameters of deodorization in mixed strains was mixed with Lactobacillus A, Lactobacillus C, tea fungus and 5.0% glucose,then fermented 6.0h at 35℃.Fermented by Mixed strians, the aldehydes, branched-chain alkanes from the volatile components were greatly reduced. Pentanal was decreased from 1.0% to 0, Heptanal was 6.52% to 0, Undecanal was also decreased from 1.17% to 0.straight-chain alkanes were increased. 2,6,10,14-tetramethyl-Pentadecane were increased to 8.1%, There were new aldehydes and alkanes produced, such as Ethyl-Bbenzaldehyde, Hexadecanal, 3-methyl-2-Butenal, Benzaldehyde, Tetradecane,Pentadecane and so on. Aromatic Class was decreased from 33.7% to 3.0%. Meanwhile, there were a large number of ethanol, acids, esters and other substances produced. the greatest substances which was fruity was ethyl acetate. the original volatile substances was more fully utilized by mixed strains than utilized by single strain, and other flavor substances were also produced more fully, there was so large content of Acetic acid ,reached to 16.32%. It covered up the fishiness to a certain extent. Therefore, the optimization parameters of deodorization is dealed with mixed strains.
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