Study On The Processing And Storage Property Of Fish Jel Product By Ultra-high Pressure Technology

At present, a new kind of fish surimi product is favored by customers due to itsfresh and tender taste, safety and health. Furthermore it is more expensive thantraditional fish ball products. Fresh fish surimi product without sterilization, is noteasy storage. Traditional fish ball product usually have hard taste because of starchaddition and high temperature steaming process. Ultra high-pressure (UHP), as anew type of food processing technology, can sterilize and keep the surimi productfresh and tender, as a result it can avoid the disadvantages caused by heating andsteaming. Previous study of surimi by UHP was emphasized on sterilization andnutrition, tenderness is less discussed and lack of new surimi product development.In this thesis, we choose grass carp as the raw material, and develop the newsurimi product—fish jel by UHP technology. The main results are as follows:(1) We produce fish jel by UHP technology, and it is fresh and tender. Theoptimum UHP processing condition was confirmed by orthogonal test: pressure of400MPa, co-temperature of30℃,dwell time of10min, compound phosphateaddition of0.3%, sorbitol addition of4%. In addition, verification tests werecarried out and properties of fish jel were obtained. The value of gelstrength,hardness, springiness, cohesiveness and chewiness was1657.313g·mm,1096.469g,0.951,0.842,986.872g respectively. Compared with traditional surimi product,the value of hardness is distinctly lower, but higher in other gelproperties. The totalnumber of bacteria is less than10cfu/g, and achieve commercial sterility.(2) Under the condition of-18℃, the storage time of fish gel can reach20dand more. The moisture of the fish jel had no significant change within20d if it istreated by more than300MPa and dwell time of10min; pH value exhibit adecreasing tendency during the storage, furthermore it is obvious in the earlierperiod and smooth in the later period. Under the pressure of500MPa, TVB-Nvalue was16.47mg/100g in the25th day， which is less than the nationalstandard(20mg/100g). The water holding capacity reduced gradually during thestorage, and the higher pressure is used, the trend is gentle. Compared with thesecond week, the content of salt extractable protein was decreased by18.0%、9.0%、 12.9%、14.6%、15.7%respectively under the pressure of0MPa,200MPa,300MPa,400MPa,500MPa in the third week.(3) The edible methods of fish jel are recommened. After thawed underroom-temperature, it is cut into3-4mm thickness and put them into hot water orchafing dish for3-4seconds; or you can dip flavoring to eat directly.