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Fish restructured products are traditional food with delicious taste and rich nutrition in China. They are very popular in people’s daily life. The development of fish restructured products is beneficial to the utilization ratio and processing of aquatic products, and can improve the economic efficiency and environmental pollution prevention. The broad prospect of fish restructured products is based on our rich aquatic resources and development of technology and equipments. The hairtail is a kind of sea water fish which is rich nutrition, high-yielding and cheap. Its utilization is limited because of rot and fish odour. In this paper, the restructured processing and characteristic of hairtail were studied, which provided corresponding experimental data for development the restructured products and meet consumers’demand. The main contents were as follows:First of all, the organic solvent extraction, acid base, tea natural antioxidant and fermentation methods were used for deodorizing the hairtail. These methods were compared and optimized by orthogonal tests with sensory evaluation and trimetylamine content as analysis indexes. The volatile components before and after deodorization were analyzed. Second, the restructured processing and characteristic of hairtail were studied. Then, fresh-keeping effect of several natural spice extracts on restructured products was studied. Finally, the flavor components of restructured products were analyzed, its main taste components and volatile components were determined by HS-SPME with gas chromatography-mass spectrometry and HPLC. The main results were as follows:(1) The tea natural antioxidant and fermentation methods were used for deodorization. The processing optimized by orthogonal tests was:fish is soaked in1.5%green tea solution60min at temperature35℃, and adding yeast2.00%, then fermenting for120min at temperature30℃. The main volatile components before and after deodorization were hydrocarbons, alcohols, aldehydes, ketones, ester. The volatile components of fish odour such as trimetylamine,1-penteny1-3-ol were decreased after deodorization.(2) The processing, digestibility and TGase enzyme mechanism of restructured products were studied. The processing optimized by preliminary selection of single factor experiment condition and response surface analysis was: adding TG1.25%, NaCl1.01%, and reacting2.97h at temperature5℃. The TG had no effect on digestibility. The SDS-PAGE gel electrophoretogram indicated that the main acting protein of TG is myosin of which relative molecular mass is200KD. The enzyme can catalyze the intermolecular cross linkage or intramolecular cross linkage of protein, making the product structure become more closer.(3) The processing of hairtail-silver carp mixed surimi optimized by orthogonal tests was:fish ratio of hairtail:silver carp was7:3, salt2%, sugar4%, water15%, corn starch20%, TG0.7%, SC0.5%, polyphosphate0.3%.(4) fresh-keeping effect of several natural spice extracts on restructured products was studied with pH, TVB-N, TBA and sensory evaluation as analysis indexes. Natural spice extracts extended shelf-life of surimi.(5) The nucleosides and organic acid were detected by HPLC. Compositions of nucleosides:AMP and Hx were detected in the samples. AMP and Hx were important taste active components. AMP was not detected in the samples.Compositions of organic acid:the high concentration of lactic acid was detected in the samples. Lactic acid was an important taste active component according to TAV values. Succinic acid and acetic acid was detected in pure hairtail restructured product. Tartaric acid and propionic acid was not detected in the samples. Volatile compounds were detected by SPEM-GC-MS. A total of58kinds of volatile compounds were detected in the pure hairtail restructured product samples, including hydrocarbons29.12%, others9.7%, aldehydes9.57%, alcohols6.49%, ester4.24%, ketonesl%. The high content compounds:ethyl alcohol,2-ethyl-1-hexanol, hexanal, heptanal, nonanal, decanal,2,6,10,14-tetramethyl pentadecane.A total of76kinds of volatile compounds were detected in the mixed surimi samples, including sulfocompounds44.4%, alcohols14.51%, hydrocarbons8.41%, aldehydes5.59%, ketones3.44%, ester3.12%.The high content compounds:ethyl alcohol, phenethanol, hexanal, heptanal, decanal, allyl mercaptan, allyl sulfide, diallyl disulfide.
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