Freshness Keeping Effect Of Different Treatment On Chilled Paddlefish Fillets During Refrigeration Storage And Chondroitin Sulfate Extraction Of Cartilage

Fresh fish and preserved fish products are welcome by the global market, however,They are, of course the most perishable food products,and their antisepsis was a focus inthis area.The fishery product shelf life only 3～4 days during refrigera-tion storage, It is aimportant topic that how to control the growth and activity of mic- roorganism, diminishthe freshness expenses,increase fishery product quality during refrigeration storage.Chondroitin sulfate is a important acid mucopolysaccharide—glycosaminoglycan.According to the research data,Chondroitin sulfate have favourable anti-aging function,and used to cure headache, arteriosclerosis, coronary heart disease, heartstroke.it could bemanufacture for facial products and health food.The cartilage source come from domesticanimal and shark,but the resource was limited,It could be extraction the chondroitinsulfate, because the bone of sturgeon is cartilage.Freshness keeping effect of different treatment on chilled Paddlefish (Polyodonspashula) fillets during refrigeration storage, extraction the chondroitin sulfate(CS) fromPolyodon spashula cartilage in this paper.Experiment 1: Freshness keeping effect of different treatment on chilled Paddle- fish(Polyodon spashula) fillets during refrigeration storageTreatment Polyodon spashula by ozone-water, and treatment Polyodon spashulafillets by Nisin or BHT, and during storage on 0±0.5℃in this experiment. By analyzingand comparing the change of sensory assessment, bacteria counts, physical chemicalindexes, the influence for bacteria counts and fat-oxidative of Polyodon spashula filletstreatment by ozone-water; the refreshing effective of Nisin on during refrigeration storage;the antioxidation.of BHT on during cooling storage. The results showed as follows:(1) It could be degrade the total bacteria with the level was 5mg/L, the tempera-turewas 4℃ozone-water treatment Polyodon spashula fillets. The incipient total bacteria was3.89×10~2 with second treatment by ozone-water, and degrade one order of magnitudecomp- are with control group during refrigeration storage(0±0.5℃),and the shelf life wasprolong 3 days,and keeping the good quality of fillets. Meanwhile, the senses score todescend fast,and the fat oxidation was intensify treatment by 5mg/L ozone-water, thesenses scores was badly, TBARS values was 0.87±0.03 mg/kg (P＜0.01) after refrigera-tion 11 days. The Polyodon spashula fillets surface has appearanced yellow brown spot during refrigeration storage.(2) It could be hold the each indexes of Polyodon spashula fillets significantly, keepthe TVB-N and K value at relatively low level treatmented by the level was 5mg/Lozone-water and 0.5g/L Nisin, Prolong the shelf life of control group attained to 11 days,The total bacteria counts were 3.47×10~5; TVB-N values were 17.33±1.55(P＜0.01); Kvalues were 41.97±0.0.54(P＜0.01), and kept the high senses scores of Polyodonspashula fillets, The Nisin group could hold the color of Polyodon spashula fish aftercooling 11 days.(3) It could be restrain the fat oxidation significantly treatmented by 0.3g/L BHT,The incipient TBARS values was 0.19±0.04mg/kg (P＜0.05), the effective wereobviously during refrigeration storage. The TBARS values put off 6 days compare withcontrol group,and 9 days compare with second treatment by ozone-water. The Polyodonspashula fillets surface has not appearance yellow brown spot after refrigeration storage17 days.Experiment 2: Study on the extraction technology of the chondroitin sulfate fromPolyodon spashulaA method of dilute alkali-enzyme hydrolysis to extract chondroitin sulfate from thePolyodon spashula cartilage was studied. Chondroitin sulfate was deposited by 95%ethanol after extraction with alkali and eliminating the protein with trypsin,then theproduct was gotten after under 60℃desiccation. Use the influential factor of alkaliextraction and enzymolysis to carry out orthogonal experiment, By analyzing the moisturecontent,proteinum, purity, characteristics of Chondroitin sulfate.The extraction condition of chondroitin sulfate was: the alkali concentration was 3%,the extraction temperature was 40℃,the weight proportion was 1:6(material:liquid),Theweight trypsin proportion was 1000:1.5(liquid:material),the enzymolysis temperature was45℃,the pH value of precipitation was 7.0.The extraction rate of chondroitin sulfate was36.52%; the purity was 97%, the proteinum was 0.075%,the moisture content was10.52%.