High Purity Extraction Of Fish Oil Polyunsaturated Fatty Acid And Preparation Of Chinese Yam Resistant Starch

The article contains two parts:(â… )Extraction of EPA and DHA from Fish Oil with Aqueous Silver Nitrate SolutionEPA and DHA belong toω-3 polyunsaturated fatty acid(PUFA)and they have great beneficial physiological function to the human body.So research of high pure EPA and DHA with commercial meaning is nowadays a very active and significant field.In the article Silver ion complexation was used to study the technology of extracting EPA and DHA from fish oil.Fish oil polyunsaturated fatty acid can be oxidized easily,so molecular distillation is used to remove molecular aldehyde ketone from anisidine value over standard fish oil,and the recovery of Silver Nitrate is also studied for industrial production.The main reseach contents and results are as follows;1.Using conversion of EPA and DHA as an assessing index,on the basis of single factor experiment,response surface methodology is used to optimize the technical parameters, the purity of EPA and DHA was detected by gas chromatography,and conversion is calculated.The optimal parameters are as follows:concentration of aqueous AgNO₃ is 4.9mol/L.complexation temperature is 0℃.ratio of fish oil to AgNO₃ solution is 1:3.76.dissociation temperature is 51℃and dissociation time is 30min.The conversion is up to 62.80%and the purity is 93.1%.2.Teconology of removing the molecular aldehyde ketone from anisidine value over standard fish oil was studied,using ISO6885 method for determining anisidine value.On basis of single factor experiment,the orthogonal test was used in optimization of technological parameters,the optimum technological condition is:input flux is 250 mL/h,input temperature is 55℃,evaporating temperature is 135℃,evaporating pressure is 0.1Pa,rotor rate is 250-300r/min.3.The recovery of Silver Nitrate was studied for industrial production.Part of Silver Nitrate was recovered by indirect reduction.sodium carbonate precipitation and water elimination with organic solution.But the three metholds have a low recovery and the Silver Nitrate recovered is not so active when used for the next complexation. (â…¡)Preparation of Chinese Yam resistant starch and physiological activity studyResisrant starch(RS)is defined as the sum of starch and products of starch degradation not absorbed in the small intestine of healthy individuals.RS has many physiological activities such as:reducing plasma cholesterol.increasing stool quantity. changing microbial community,increasing some short chain fatty acid in colorectal. decreasing feces pH,and so on.There is no report on the research of Chinese Yam resistant starch physiological activity.Preparation of Chinese Yam resistant starch and physiological activity was studied in this article.The main reseach contents and results are as follows:1.Using RS conversion as an assessing index,on basis of single factor experiment,the orthogonal test was used in optimization of technological parameters,the optimum technological condition is:starch concentration is 20%.autoclaving treatment temperature is 121℃,pH is 6.0.autoclaving time is 25min.incubating time is 24h. incubating temperature is 4℃.With these conditions,the content of RS can reach to 9.82%.2.Physicochemical properties of Chinese Yam native starch and RS was compared,the result showed that RS has a lower water capacity,,the content of crozzle and SO₂ are almost invariant.Solubility_is much lower than native starches in water and transmittance decreased.3.The influence of RS on mice blood sugar was studied,the result shows that:RS can cut peak and fill vally of mice postprandial blood glucose;reasonable content of RS dietary is more useful for controlling blood sugar,RS can delay the increase of blood sugar induced by alloxan,contain weight reduction,help improving the life quality of model mice.4.Influence of yam RS on intestinal flora of healthy was studied,the results showed that yam RS can increase bifidobacterium and decrease enterococcus.enterobacter.