| The vinasse fish was a kind of traditional freshwater fishery production, which was particular and widely accepted in china due to its unique taste and smell character. Currently, the small workship manner was the traditional processing method of the vinasse fish, and the production cycle was very long, and its instability of the quality of the product. The freshwater fish are rich in protein with high nutritional value, low price. The yield of fresh water fish increased in recent years, but its processing utilization rate was low due to its soil smell and undeveloped processing technology. By using the sturgeon as the vinasse’s raw material, and research the wet salted processing, hot air drying process, intermittent vacuum wine lees pickling technologies, vacuum drying technology, cold storage characteristics and the properties of the fat hydrolysis and oxidation during the processing of the vinasse product. The production’s costs could be effectivly reduced and the values of vinasse’s industrial application could improve greatly.Firstly, the wet-curing process of vinasse sturgeon was evaluated by response surface method. The effect of different addition of the salt added, the wet-curing temperature and time on quality of vinasse sturgeon was studied by the mono-factorial experiment. Based on these results and the principle of Box-Behnken of response surface methoddogy, a temary quadratic equation for the value of sensory evaluation was built. By analyzing their corresponding contour plots and the response surface plots as well as solving the quadratic equation, the experimental values were shown to be significantly in good agreement with predicted values since the adjusted determination coefficient was 0.974. Result indicated that the significant external factors affecting the quality of products were the addition of the salt added. The optimal clarification conditions: the salt added 14%, wet-curing temperature 10℃, curing time 10.5h. The value of sensory evaluation is 90.Secondly, effect of the hot air drying temperature on the quality, colour and the texture of the vinasse was researched in this paper. The study found that the hot air drying temperature has significant effects on the fat oxidation and proteolysis of the vinasse fish, the degree of the fat oxidation and proteolysis of the sample were dried by the 40℃and 50℃ were higher than the sample were dried by the 60℃and 70℃, but the lever of the quality deterioration of the sample were dried by the high temperature was serious. The products that were dried by low temperature were full of flexibility and its appearance was golden yellow and high in nutritional value. The optimal reactive temperature of endogenous enzymes is 37℃, was closed to 40℃, therefore, the lever of the quality deterioration of the sample were dried by the 40 temperature was serious than the sample were dried by the 50 temperature.Thirdly, Effect of intermittent vacuum wine lees pickling technologies on the quality of drunk fish was studied, the research found that the quality of drunk fish was the best when the vacuum wine lees pickled at 25℃ for 6 days in rice wine lees with 0.09 MPa vacuum degree. The value of total sugar, total acid and amino acid nitrogen of drunk fish were higher than other situation, which is better in sensory evaluation value and the colour and the texture and the nutritional value than products obtained in other conditions, and the lever of the fat oxidation and proteolysis of the vinasse fish was lower than other situation.Fourthly, Effect of different kind of dry methods on the quality of drunk fish were measured and analyzed. The research showed that the color and the sensory evaluation value of the samples that was dried by vacuum drying were better than other dry methods, and its aerobic bacterial count value was less than other dry methods. The color and the sensory evaluation value of the samples that was dried by hot air drying were worse than other dry methods, and its aerobic bacterial count value was higher than other dry methods. After be dried by four drying methods, all of the TVB-N value, total fat(wet weight) value and TBA value of samples were improved. The TBA value of the samples that was dried by vacuum drying was lowest than other dry methods, and have the most higher total fat value than other dry methods, although the value of TVB-N of samples was higher that was dried by vacuum drying than the samples by other two drying methods, but which was up to the China National Standard.Fifth, the quality variation and the fat oxidation and proteolysis of the drunk fish were researched during the process. The research found that the moisture content of the drunk fish were decreased at first, then increased, and then decreased again, the hardness of the drunk fish were decreased at first, then increased. The salted processing was advantaged for the formation on the color of the vinasse fish, but the processing follow the salted processing was disadvantaged for the formation on the color of the vinasse fish. The value of crude fat was decreased significantly during the wet salted and hot air drying processing. During the whole processing, the phospholipids content of sample was decreased significantly, which was positively correlated with the significant decrease(P<0.05) in the activities of acid lipase and neutral lipase. The value of TBA was increased during the whole processing, which was positively correlated with the significant increase(P<0.05) in the activities of LOX. During the whole processing, SFA content was increased at first, then it decreased, MUFA content was increased at first, then it decreased, which was positively correlated with the significant decrease(P<0.05) in PUFA content. It shows that the process of the vinasse fish product was advantaged for the oxidation of unsaturated fatty acid, and released the saturated fatty acids, finally, improved the content of SFA of the sample.Sixth, The quality variation of drunk fish with grass carp, tilapia, sturgeon stored at 0℃ were evaluated by microorganism and chemical indicators. The results showed that the moisture content of three kinds of drunk fish were increased with the extension of storage time, during the cold storage, the hardness of three kinds of drunk fish were decreased, and the grass carp was the lowest degree of hardness decreased. The aerobic bacterial count of three kinds of drunk fish(grass carp, tilapia, sturgeon) have already over the safety range, at 21 days after storage, and could not be edible. From the start to the end of cold storage, the value of TBA of drunk sturgeon is the highest one than others, the value of TVB-N of tilapia was up to 30.99mg·100g-1 at 18 days after storage. The speed of protein degradation of drunk tilapia was lower than others. |
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