Study On The Preparation And Refining Processing And Functional Quality Of The Silver Carp Antioxidant Peptide

As a kind of direct consumption of freshwater fish，the economic and socialbenefits of silver carp is decreasing. Carrying out the research on deep-processingof low-value freshwater fish has become an important way to enhance the economicvalue of the freshwater fish though making freshwater fish processing to adeveloped serialization，diversification and high-added value industry．In thispaper，silver carp proteins were hydrolyzed to prepare high antioxidant activitypeptides under the combination of complex enzyme and multi-directed enzymatictechnology, the dynamics model and the industrialization production conditions ofenzymolysis technology was then established，high antioxidant activity peptideproducts were finally prepared directly and efficiently．The odor components ofsilver carp antioxidant peptides were also qualitative detected by GC-MS, in orderto obtain refined silver carp antioxidant peptides, activated carbon andion-exchange resins were used to deodorize of the odor for the silver carpantioxidant peptides．At last，the properties of the silver carp antioxidant peptideswere studied．In the study of enzyme hydrolysis，four different kinds of enzymes were usedto hydrolyze the silver carp meat，they are Alcalase2.4L，Flavourzyme，Trypsin andNeutrase．After comparative analysis，Alcalase2.4L was proved to be the besthydrolysis enzyme． The optimal conditions have been found by single factorexperiment： temperature50℃， volumes of enzyme24AU/kg， substrateconcentration15%，pH9.0，time60min．After the complex selection，Trypsin wasselected to be the other part of the complex enzyme to combine with Alcalase2.4L． With antioxidant activity as indicator， the optimal complex-enzymehydrolysis process conditions were found by response surface experiments:Alcalase2.4L， temperature50℃， volumes of enzyme24AU/kg， substrateconcentration15%，pH9.0，time59.12min；Trypsin，temperature45℃，volume of enzyme35.5AU/kg，pH9.0，time82.24min．the content of the silver carpantioxidant peptide products were as follow：content of soluble nitrogen70.84%，content of polypeptide9.38%，moisture21%，ash content25.67%，DPPH freeradical scavenging rate is19.33%with the polypeptide concentration of2mg/mL．After detected by GC-MS， oleyl alcohol can be used as a referent ofdeodorization．Considering Peptide and DPPH free radical scavenging loss rates asthe index，combined with the sensory evaluation，the deodorization technology ofactivated carbon and ion-exchange resins on the effect of silver carp antioxidantpeptide has been studied．The optimal conditions were found by single factorexperiment: volume of activated carbon1.0%(w/w)，temperature35℃，time1h，D113ion-exchange resins，.concentration of the sample10.0mg/mL，pH of thesample6.0，speed2.0BV/h，after comparative analysis，the deodorization effect ofactivated carbon was found to be better than ion-exchange resins．After investigating the physical and chemical properties of silver carpantioxidant peptide， the antioxidant peptides was found with the property of goodsolubility， low viscosity and low hydrophobicity. High-performance liquidchromatography (HPLC) was used to detect the molecular weight distribution ofsilver carp protein and silver carp antioxidant peptide，the result indicated that，components below1000Da of the refining silver carp antioxidant peptides took97.3%percent of total content， and most components concentrated between500~190Da and around60%percent of the total content． The amino acidcomposition of silver carp proteins and silver carp antioxidant peptides weredetected by amino acid analyzer，the result indicated that，most amino acids didn’thave significant change on the content，some ones contributed to the antioxidantactivity increased，such as aspartic acid and glutamic acid．...