| In this paper,Euphausia superba was used as the research object,and the nutritional components of Antarctic krill were determined and analyzed for six consecutive months.The effect of six kinds of calcium salts and ultrasonic treatment on the different forms of fluoride removal in Antarctic krill meat was studied,and the defluorination agent with ideal defluorination effect was selected.The preparation process of the Antarctic krill hydrolysate was optimized using papain as the tool enzyme;the enzymatic hydrolysis combined with the organic solvent was used to extract the Antarctic krill oil.Preparation process and optimization of preparation conditions.1?In this paper,the basic nutrient contents,amino acid and fatty acid content of Antarctic krill from April to August in Antarctica 48.1 were determined,and the nutritional value of Antarctic krill was analyzed and evaluated systematically to provide reference for the processing and utilization of Antarctic krill.The results showed that the water content of Antarctic krill ranged from 76.65% to 82.69%,the protein content ranged from 13.07 % to 15.15 %,the fat content ranged from 1.13% to 4.36%,and the ash content ranged from 1.31% to 2.54%.The total amino acid content ranged from99.83 to 151.33 mg/g,the essential amino acid content ranged from 41.63 to 64.66 mg/g,and the latter ratio(E/T)ranged from 41.01% to 42.73%.Krill essential amino acid index(EAAI)is close to 1 and the ratio is balanced,The limiting amino acid is Valine;29 fatty acids were detected in Antarctic krill,including 8 monounsaturated fatty acids,ranging from 26.03% to 32.54%,mainly based on C16:1 and C18:1n9c,11 kinds of polyunsaturated fatty acids,the content range of 29.18% to 38.09%,mainly EPA and DHA,?-3 /?-6 value between 2.96--4.37,the ratio is appropriate.Based on the comprehensive analysis,the nutritional value of Antarctic krill is extremely high and it has broad prospects for development and utilization.2?In this experiment,based on the determination of different forms of fluoride inAntarctic krill meat,ultrasound-assisted six different calcium salts were used to defluorinate the Antarctic krill shrimp meat.The results showed that: in the Antarctic krill meat,the different forms of fluoride from high to low is: exchangeable fluorine>soluble fluoride>oxidation fluoride>residue fluorine>organic bound fluoride,which accounts for 32.91%,25.59%,17.02%,15.13%,9.35%,respectively,of the total fluorine content,of which the exchangeable state Fluorine and water-soluble fluorine predominate.The effect of ultrasound-assisted calcium defluorination was greatly improved compared to the use of calcium salts alone,among which calcium citrate,calcium chloride and calcium lactate had the best defluorination effect,and the defluorination rates reached(40.81±3.29)%,respectively(40.15±0.06)% and(40.06± 1.42)%,there was no significant difference between the three groups(p> 0.05).Among them,water soluble fluorine and exchangeable fluorine were bioavailable fluorine,and the total removal rates of the two calcium salts,calcium lactate,calcium chloride and calcium citrate,reached 68.66 %,65.78% and 62.69 %,respectively.The effect is best.The oxidized fluorine can be partially removed.The defluorination rates of calcium citrate,calcium chloride,and calcium lactate are 27.5%,24.45%,and23.14%,respectively;organic bound fluorine and residual fluorine are difficult to be After removal,the highest removal rates were 11.45% and 6.82%,respectively.However,the oxidized fluorine,the organic bound fluorine and the residual fluorine are non-effective fluorine,which is not harmful to the human body.Therefore,calcium lactate,calcium chloride and calcium citrate are ideal defluorinating agents.3?Antarctic krill meat was used as raw material,and papain was used to prepare Antarctic krill enzyme solution.Using the degree of hydrolysis and recovery of protein as evaluation indicators,a single factor experiment was conducted first to examine the effects of enzyme addition amount,substrate concentration,pH,enzymolysis time and temperature on the enzymatic hydrolysis process,and then orthogonal experiments were performed to determine the most.Excellent process conditions.The experimental results show that when the enzyme dosage is 0.5%,pH 6,the substrate concentration is 6%,the temperature is 50?.,and the time is 4h,the degree of hydrolysis is 42.14% and the protein recovery was 89.53%.4?Using papain as a tool enzyme,the enzymatic hydrolysis of Antarctic krill oil was studied.The effects of enzyme addition amount,pH,enzymolysis time,and temperature on the yield of shrimp oil were studied by single-factor experiments.Theoptimum conditions for enzymatic hydrolysis were: 0.6% enzyme addition,pH 5.5,the enzymolysis time is 2.5 h,and the enzymolysis temperature was 50?.At this time,the yield of shrimp oil was 71.28%.The obtained shrimp oil had an acid value of 6.58 mg/g,an iodine value of 134.27 g/100 g,a peroxide value of 3.16 mmol/kg,moisture and volatile matter of 0.63%,insoluble impurities of 0.11%,and unsaturated fatty acids in shrimp oil.62.2%,The content of EPA and DHA is as high as 23.80 % and 12.55 %,high nutritional value,with good prospects for development and utilization. |
PDF Full Text Request