Study On The Nutritional Quality Of Abalone In Different Varieties,Habitats And Aquaculture Models,and The Function Of Polysaccharide In Abalone

As delicious marine product,abalone is favorited by the majority of consumers at home and abroad.It has a high food value and medicinal value.With the development of aquacultural technologies and the growing of aquacultural yield,China has been the first abalone breeding country.In order to make the development and utilization of abalone more comprehensive,its processing technology and processing products develop to high-tech,high value and high utilization.At the same time,with the increase of consumer quality and safety awareness,consumers are paying more attention to abalone nutritional quality.And abalone produces a large amount of visceral scraps during processing,while the abalone viscus contains a large number of functional active ingredients.In view of this,this topic makes abalone from different breeds,different culture modes,and from different places as the research objects.The nutritional quality evaluation of abalone was carried out and the functional activity of polysaccharide was extracted from abalone.The main research content and conclusions are as follows:（1）Abalone nutrition quality evaluation.The composition of moisture,ash,fat,protein,total sugar,amino acids and fatty acids in the muscles abalone samples from different breeds,different culture modes,and from different places were detecting and analyzing.And analyzing the nutrient composition data of abalone,we found that Haliotis Fulgens is a high-quality amino acids product for consumers,and Hybrid abalone was an effective supplement of the monounsaturated fatty acids required by the body.Shallow sea bream culture and factory culture of abalone were more suitable breeding models.Shandong abalone is slightly better than abalone in Guangdong,Fujian and Liaoning provinces in terms of taste and nutrition.According to all of the nutrition analysis results of abalone,it was found that the contents of palmitic acid,oleic acid and EPA of abalone were high,It is indicated that abalone is a low-fat and high-protein marine animal protein and the fat content is mostly polyunsaturated fatty acids.（2）Preliminary establishment of abalone traceability model.By determining and making correlation analysis of 13 major elements and trace elements（Na、K、Mg、Ca、Fe、Zn、Cu、Ni、As、Al、Mn、Cr and Se）in muscle of four major breeding provinces abalone samples from Guangdong,Fujian,Shandong and Liaoning.After using the principal component analysis method to reduce the dimensions of these data,six elements were effectively extracted from the 13 elements as the main components,and the cumulative variance contribution rate reached to 89.872%.At the same time,Ca,Se,Na,Fe,Mn,K,and Ni were 7 kinds of characteristic elements of abalone from different habitats,and a comprehensive model of principal components was established:F=0.2777F1+0.2652F2+0.1295F3+0.1066F4+0.0656F5+0.0541F6,among them,F₁represents the first principal component,and the other F₂-F₆ are the same.The establishment of the model provided a certain basis for the theoretical basis for the origin of abalone.（3）The extraction of polysaccharide from abalone.We extracted the abalone visceral polysaccharides by enzymatic method with hybrid abalone visceral as raw material,and the polysaccharide yield was as the evaluation indicator.Six kinds of proteases were screened out as suitable enzyme preparations for extracting visceral polysaccharides from abalone.On the basis of single factor experiment,using the response surface to optimization the larger effect of protease condition on polysaccharide yield,and the optimal protease conditions were determined by regression analysis.The results showed that trypsin was a suitable enzyme preparation for abalone visceral polysaccharide,and the optimal extraction condition was obtained as follows:solid/liquid ratio 1:49 g/mL,pH 8.6,enzymatic dosage 2.1%,time 2 h,temperature 37℃.Under the optimal conditions,the abalone visceral polysaccharide yield was 6.97%.It provides technical support for the extraction and high-value utilization from abalone visceral polysaccharides.（4）Evaluation of antioxidant activity of abalone viscera polysaccharide.There antioxidant indexes,DPPH free radical scavenging rate,·OH radical scavenging rate and reducing power of abalone visceral polysaccharide（AVP）were determine,and the antioxidant capacity of AVP was evaluated;meanwhile,the AVP was isolated by glucose gel G-100 column layer and the antioxidation abilities of isolated fractions were studied and compared.The experimental results showed that the concentration of abalone visceral polysaccharide（AVP）was in the range of 1-10 mg/mL,and the linear equation of DPPH radical scavenging rate is:y=9.715x+1.0182,R²=0.9958,IC₅₀ value was 5.04 mg/mL.The linear equation of·OH radical scavenging rate was:y=6.2778x-8.5275,R²=0.9603,IC₅₀0 value was 9.32 mg/mL;the linear equation of reducing power was:y=0.0782x+0.0045,R²=0.9989,and the value of A_{700 0.2} is 2.5mg/mL.AVP has a certain antioxidant capacity,but its antioxidant capacity was weaker than Vc.AVP can be separated into two components（AVP1 and AVP2）by G-100column chromatography;both AVP1 and AVP2 had certain antioxidant activity,and AVP1 had higher antioxidant capacity than AVP2.Therefore,AVP1 had a good prospect of development and utilization in the fields of antioxidant additive and health products.